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"checking cylinder compression" transistions to no start

Discussion in 'XJ Technical Chat' started by moellear, May 18, 2011.

  1. RickCoMatic

    RickCoMatic Well-Known Member

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    I guess your next move is:

    Checking your Timing.

    (On the occasions where Timing was incorrect; the Engines with the errant Timing would not complete a revolution without bumping.)

    I hope you didn't do damage.
    The procedure calls for a Hand-checked turning-over of the Engine to PROVE the Cams are Timed right before doing anything else.
     
  2. Rickinduncan

    Rickinduncan Member

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    If he checked his valve clearances after the new piston was installed, - even with the bad cam timing, shouldn't he have felt some resistance and he was hand turning the engine over? As a second thought - if he checked his valve clearance after the rebuild, then checked his valve clearance now - wouldn't that tell him whether or not he's got a bent valve? I'm also a little suspicious of the low compression on both inside cylinders. I'd also be looking at an improperly torqued head gasket. What are your thoughts ?
     
  3. RickCoMatic

    RickCoMatic Well-Known Member

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    Low Compression on Adjoining Cylinders can indicate a Gasket Issue.
     
  4. moellear

    moellear Member

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    gasket issue? a gasket that's so thin how does it result in low compression? really confused if you can't tell and starting to think this whole idea of a rebuild was a big mistake. as a young pup (24) i'm losing patience and this bike surely has tested my patience.

    a wet compression test is in order first thing in the morning and I won't be running this for a while. in fact, just this afternoon it stalled on me a mile down the road at a stop sign so I pushed it back home since it refused to fire back up. needless to say my motivation is slipping day by day
     
  5. waldo

    waldo Member

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    throttle wide open during compression test? 2@3 dont even have enough pressure to support combustion quit screwing around and do a leak down test find the problem fix it and go ride.
     
  6. moellear

    moellear Member

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    best advice ever
     
  7. pirok

    pirok Member

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    Well I will go back a step. New rings presupposes cylinder honing.
    That vill make the cylinder walls a bit coarse and the new rings and the cylinder will adapt to each other by simple wear.
    Thats why you have to drive at low speed/rev. the first 500 miles or so. (makes a lot of heat the first 50 miles).
    Then after a 1000 miles or even more you can use the compression test to compare with the specs. Of cause you can compare between cylinders after a 100 miles to see if something is wrong.
    Did you do the honning thing?

    If you have a bent valve thats not impossible to fix.
    Be a little patient and ask this forum before action, could save time and money for you.
     
  8. moellear

    moellear Member

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    yes, a slight deglazing of all four cylinder jugs was complete before rings were installed using the three stones on a spring with drill loaned from AutoZone. ring gap test was also measured and within spec.

    so if compression improves after wet test I learned that the culprit is most likely the rings. I installed new rings on all four pistons a few months ago and this morning completed dry and wet tests =

    DRY - #1=110, #2=75, #3=65, #4=90
    WET - #1=140, #2=140, #3=140, #4=140

    these results shocked me. the only conclusion,,, well I'm gonna stop there and ask before any more action. could save me more time and money. can anybody with rebuild experience explain why my compression has changed this much? I would surely think even immediately after the new rings were installed that compression should at least be consistent during a dry test correct?

    How can you tell if it is the head gasket?
     
  9. pirok

    pirok Member

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    Immediate reaction would be - worn out cylinders/rings. In this case - not enough miles to make rings/cylinder adapt to each other.
    What about the rings, did they moves freely on the pistons. When they are compressed they could easily get stocked.
    I dont know if a wet test have any influence on a leaking gasket, you could try to tighten the cylinder head again with specified torque.

    How many miles since the new rings were installed?
     
  10. moellear

    moellear Member

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    maybe 25 miles on the road and 2~3 hours of total run time
     
  11. pirok

    pirok Member

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    Well, then i would say: try to get a couple af hundred miles on the clock and see if it ain't changing for the better. I mean that is quite realistic.
    I've tried that tactic twice with good results.
     
  12. RickCoMatic

    RickCoMatic Well-Known Member

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    The "Wet Test" results points at Rings.

    Did you look to be sure that the Rings were in the right Configuration?
    Top.
    Bottom.
    Etc.
     
  13. moellear

    moellear Member

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  14. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    I was beginning to wonder about this idea myself.

    The motor was reassembled meticulously; I wonder if the head got torqued down correctly or there might not be a head gasket issue of some sort. It would explain a lot of things.
     
  15. moellear

    moellear Member

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    what worries me is the results of the wet test. i was expecting to see no change honestly between wet and dry
     
  16. RickCoMatic

    RickCoMatic Well-Known Member

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    There are two Cylinder Head Studs at the Centerline, ... facing downward.
    Maybe he got ahead of himself.
    It happens.

    The New Rings need to Bed-In, ... But, the numbers are still too low for there not to be something amiss.
     
  17. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    If the head gasket didn't seal properly between #2 and the camchain gallery and #3 and the camchain gallery, it's really possible.

    No change would have meant valve damage. Something else is going on, obviously.

    And a shot of oil "sealed" whatever that anomaly is; if not the rings it could very well be the head gasket.

    So let's review:

    When you installed the rings, you verified which side was up for each and every ring.

    You "staggered" the ends of each ring (or set) according to the diagram in the manual.

    End gap was verified on all rings (we covered this already, I believe.)

    You used a new head gasket. No sealant; or maybe on one side.

    You got the head gasket from Len.

    The gasket surfaces on both the head and cylinders were so clean you could have licked them.

    All head bolts were tightened to spec, gradually, and in sequence according to the book. You didn't forget the ones underneath in the sequence.

    Now here's the $64,000 question, and I almost hate to ask it:

    When the head was off, were the "mating" surfaces of the head and cylinders checked for flatness? Did you lay a straightedge over the head, across the cylinders to ensure it was still straight; and the same for the cylinder bank? I'm concerned that whatever disaster originally befell #1 could have warped the head or cylinders at the thin camchain gallery casting web, it's not unheard of.

    Now the "bad" news: You'll know for sure when you pull the head back off. (Sorry.) If the head gasket let go into the camchain gallery you'll see it.
     
  18. moellear

    moellear Member

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    yes.

    no. this may be a major culprit of a problem. I did not see anywhere how the rings were suppose to be staggered in my haynes manual. Since I could not utilize ring compression tools because they were too large from AutoZone, my brother and mom helped pinch the rings at the end gap as the jugs were lowered over the pistons (we did 2 pistons each time to lower the jugs over pistons = two people for a piston/rings feeding and one to lower the cylinder block). therefore the rings aren't staggered and if they didn't shift some of them may have a gap at the same location for both top and second rings.

    yes.

    Yes. And no, I used a copper sealant from Len on the base of each gasket.

    yes.

    lol yeah

    yep. and no I didn't forget those underneath along the centerline

    no I didn't check for flatness. There was no distinguishing features that looked wrong and the head looked good as new. I really have my doubts to something as serious as warp damage is present to the head.

    so you're suggesting I remove the head at least to examine the gasket? what would be the next step if nothing is out of the ordinary once the head is removed? whew, good thing I don't have a full-time job yet...
     
  19. RickCoMatic

    RickCoMatic Well-Known Member

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    The Warp would not be discernible to the Naked Eye.

    You have to Lay a Straight Edge straight across the Head and from opposite corners.
    You see if a Feeler Gauge can be inserted beneath the Straight Edge.

    I'm not a Member of the "Squeaky Clean Mating Surfaces" squadron.

    I buy a little Insurance.

    I spray some Permatex High-Tack Spray-a-Gasket into a Tuna Can.
    Using a nice "Artist" Brush, ... I paint the Sealant on the Head and the Block.
    Leave it alone for awhile.
    Spray BOTH Sides of the Gasket.
    Leave it alone awhile.

    Once thing get so sticky that it will rip a Latex Glove right off you, ...
    Position the Gasket on the Block.
    Bring-over the Head
    On she goes.
    Rap it into place with a Rubber Mallet. (Love taps!!!)

    Wipe the Studs & Spacers with Oil
    Lube the Acorn Nuts.

    Torque.
    20% of Specs.
    70% of Specs.
    Final Torque to Specs
     
  20. moellear

    moellear Member

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    the head is off and nothing out of the ordinary like bumps or bruises, just oil here and there from the wet test. what should I be looking for?

    I will share besides everything I answered last night to fitz's questions;

    1. during head disassembly i noticed the four acorn nuts in the center closest to cam chain were a lot looser (as if they never got fully torqued down)

    2. the head gasket is loose and not sticking around cylinders 2, 3, and cam chain. however, its stuck around the edges and 1 & 4. I would like to re-tack like Rick suggests so removal is optimal only if I don't damage it. your thoughts?

    do you think between a combination of 1 & 2 that the compression would be that low? what about the improvement of cylinders 1&4 from 110 to 140 psi? i apologize if I'm making my problems like a big drama queen. just sharing my experience with a 30 year old machine in its resurrection phase and I don't have as much knowledge behind this process to get it right, hence the timing screw-up for example. thanks for the understanding and any help you can offer
     
  21. moellear

    moellear Member

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    this bike is falling apart..

    when engaging the starter button, it cranks maybe once and then clicks rapidly from the solenoid about 3~4 clicks in a row. obviously something is not connected or else the solenoid is toast. one or the other, I can't determine. anyone know why?

    battery has been charging all morning
     
  22. RickCoMatic

    RickCoMatic Well-Known Member

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    It might jut be the Starter Commutator needing to be cleaned-out.

    The Electric-end of the Starter gets "Carbon-Dusty" and the Starter just Shorts-out to Ground.

    Then, again ... you might need Brushes.
     
  23. moellear

    moellear Member

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    Rick I've researched and came up with only info from you to several people to clean the commutator. where is it though? lol
     
  24. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    It's the thing the brushes contact.

    Which book are you using again? Starter coverage is different...
     
  25. RickCoMatic

    RickCoMatic Well-Known Member

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  26. moellear

    moellear Member

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    thanks guys. with my brother's HS graduation this weekend and working part-time, its back in the barn for a couple days. I've been trying to put the reins on myself to not rush anymore. Its disturbing how this much work has lead me to this point ~ new rings, new piston, valve job, re-torque the head correctly this time, fix/learn timing issues are important, the list goes one ~ oh well, its more than some people can say they've ever done to a motorcycle

    the battery just didn't seem to have enough power to crank (brand new battery two weeks ago keep in mind). got the heavy duty battery charger for cars and boat out and low & behold the thing skipped the clicking bull-crap and fired up. ran the motor til I discovered a crack in the head near an allen bolt retaining the valve cover - suppose I'm too strong for my liking...? "it's always something".. is there anything I could use to seal a crack near top of motor head? its near the top where valve cover gots bolted down?

    for giggles I thought I'd try to fire it up again without any charger 5 minutes later. and it wouldn't fire?! just crank and the solenoid made clicking noises and then more abrupt noises from near starter/stator area clunked making abnormal sounds so I quit. rolled it into the barn and left it before I was tempted to kick the darn thing
     
  27. Robert

    Robert Active Member

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    no. this may be a major culprit of a problem. I did not see anywhere how the rings were suppose to be staggered in my haynes manual. Since I could not utilize ring compression tools because they were too large from AutoZone, my brother and mom helped pinch the rings at the end gap as the jugs were lowered over the pistons (we did 2 pistons each time to lower the jugs over pistons = two people for a piston/rings feeding and one to lower the cylinder block). therefore the rings aren't staggered and if they didn't shift some of them may have a gap at the same location for both top and second rings. [/quote]

    This would cause a serious drop in cylinder compression if all of the ring gaps were lined up. They would leak prodigiously. They need to be clocked 120 degrees out from one another (think of the Mercedes Benz symbol). Given the method of assembly you outlined, it is anyone's guess if you are lined up for a problem. Best to be certain and pull those jugs. You can make a ring compression tool out of a sheet of plastic (milk jug or like material) and a pair of pliers. Just cut a lengthy strip and wrap it around the piston, grasping the bitter ends with the pliers to squeeze the rings.
     
  28. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    I've always uses strips cut from an appropriate diameter CAN and hose clamps, with the resultant occasional sliced finger. Plastic would make MUCH more sense. Good tip.
     
  29. SQLGuy

    SQLGuy Well-Known Member

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    Is it the head that's cracked, or the valve cover? If the valve cover, what I would do is pull back off, clean it up, and take it to a job shop to have someone weld it. Shouldn't be more than $30 or so, and it will be a permanent, proper, fix. If the valve cover gasket and donuts aren't pretty new, I'd also put new ones on. The valve cover bolts ONLY get about 7 lb ft of torque.

    If the head is cracked, go back to square 1, I think...
     
  30. SQLGuy

    SQLGuy Well-Known Member

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    This would cause a serious drop in cylinder compression if all of the ring gaps were lined up. They would leak prodigiously. They need to be clocked 120 degrees out from one another (think of the Mercedes Benz symbol). Given the method of assembly you outlined, it is anyone's guess if you are lined up for a problem. Best to be certain and pull those jugs. You can make a ring compression tool out of a sheet of plastic (milk jug or like material) and a pair of pliers. Just cut a lengthy strip and wrap it around the piston, grasping the bitter ends with the pliers to squeeze the rings.[/quote]

    I had read elsewhere (I think it was in the instructions that came with a set of Deves rings for a car) that rings will normally rotate around the piston, and that staggering the gaps would only make much difference one way or the other when they were first installed... the rotation eventually evening everything out regardless. Not true? Or only true for certain rings or engines?
     
  31. moellear

    moellear Member

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    the crack: yes unfortunately its on the head directly below the bolt on the corner to fasten the valve cover. $hit outta luck I know... haven't determined yet what to do with it since it does leak somewhat when running

    the rings: honestly I don't wanna pull the cylinders off again. it only makes sense but with such a tiny end gap (millimeters) sometimes I ask myself is it really worth it? Yes I would like the bike to perform at its best so I'm considering it though. thanks for the tip Robert! the compression ring tool was just not gonna work because of its size and location near bottom of engine crankcase
     
  32. SQLGuy

    SQLGuy Well-Known Member

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    It may be possible to weld the crack on the head without warping it, but warpage would be my concern there. Welding generates a LOT of heat. The $30 weld crack repair may lead to a $70 milling job.

    Of course, if the head is already warped (I remember a post earlier in this thread about checking it for flatness), then there'd be nothing to lose with the welding.
     
  33. RickCoMatic

    RickCoMatic Well-Known Member

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    This Article was printed in a Society of Automotive Engineers Journal many-moons ago.

    (AE = Automotive Engineers)

    Institution of Diagnostic Engineers
    RING GAPS vs KNOWLEDGE GAPS

    During school summer holidays there occurs a period known as the "silly season" when breaking news is slack and newspapers, radio and TV issue forth all sorts of drivel to justify their existence.

    In our industry I sometimes think that we use ring gaps to fulfill a similar purpose – and we do it all year round. There are more old wives tales about ring gaps than any other facet of our job, so lets spend a while and bin a few of them.

    Frequently I hear in court that when an engine is dismantled it is discovered that the ring gaps were not staggered when they were installed. Frequently I read workshop manuals that go into great detail on the necessity to stagger ring gaps. Frequently these manuals specify ring gap limits – which is yet another myth we can disprove before we are finished.

    In days gone by, some compression rings used to have a ‘threepenny bit’ expander behind them. These braced against the base of the ring groove and forced the ring onto the cylinder bore but these are very much the technology of yesteryear and, as such, an exception to what I am about to say.

    Piston rings are free agents and can rotate or not rotate as they see fit. They are not in touch with the base of the groove and neither are they trapped between the upper and lower faces of the groove. The rings are entirely free to rotate – except where a stop peg is fitted – so what's the point in staggering the gaps on installation?

    We used to work on a minimum of 0.020" back clearance on radius or, to put it another way, the inside diameter of the ring when installed in the cylinder must be at least 0.040" bigger than the groove root diameter. Minimum side clearance was generally held to be 0.0015" and if you could fit a 0.006" feeler gauge in the groove along with the new ring then the groove was "goosed" so the piston was replaced.

    The piston ring was manufactured with a tangential load – the force with which the ring presses against the cylinder wall – but apart from that it is completely uncontrolled. There is no way, under these circumstances, that you could prevent the ring from turning so, to repeat the question, why stagger the ring gaps on installation?

    Staggering ring gaps when installing pistons is every bit as daft as having four tires fitted and placing all the valves at "twelve o'clock". One trip to Ice Cream Stand and they end up all over the place.

    Equally silly are those who expect ring gaps to stay staggered when the engine is in operation. When there is clearly nothing to prevent the ring from rotating, why should the gaps stay staggered?

    More than one county court judge has fallen for the hocus-pocus that because the gaps were in line when the engine was dismantled, they must have been in line when installed. Absolute nonsense! Yet the inclusion of such rubbish in workshop manuals does admittedly give it an air of authority.

    When you think about it, you don't need me to tell you – but I will anyhow – that rings do rotate in operation. Every now and again the gaps do line up – and once lined up there is a tendency for them to stay lined up at least until the vehicle hits the next pothole in the road when one or other will rotate and break the line. Staggering ring gaps when installing rings is a myth that we can throw-out forthwith.

    Even worse is the preoccupation with the size of the ring gap. Yes, there is a minimum but this varies considerably depending on the material used. Normally 0.003"/0.004" per inch of bore size is given but where, for example, low expansion SG (spheroidal graphite) iron is used, it can be considerably less.

    It’s no problem if the gap is too small because it can, in the final analysis, be filed bigger but what do you do if it's too big? You cannot stick a bit extra in there!

    Well, the answer to that was that you melted them down and started afresh – until AE research asked the question, "What is too big?" and set out to quantify that.

    The results were interesting – very interesting – and what you are about to read was kept quiet because it bestowed an enormous commercial advantage on AE. This is probably the first time the information has been published although the research was undertaken in the late 1970's – almost 25 years ago.

    A Ford Kent engine was stripped and fitted with compression rings which had end gaps of 0.015" when fitted in the bores. The engine was wired up with the usual telemetry to measure blow-by and oil consumption and then run in one of the test cells. After making due note of the blow-by and oil consumption, the engine was stripped and fitted with new compression rings with gaps of 0.025" and the test cycle repeated.

    These rings were subsequently replaced by ones having end gaps of 0.035" and the test cycle repeated again. It had been planned to stop at 0.035" gaps ---------->BUT, the results were so interesting that it was agreed to proceed to 0.045” and then not to 0.0055” but to 0.0625” – 1/16"!

    Whoever heard of rings with 1/16” gaps – a ridiculous figure – but the interesting thing was that the increase in blow-by and oil consumption at 0.0625” was only marginally above the figures obtained with 0.015” gaps.

    Practical tests established that the gap was not the villain of the peace.

    To all practical purposes the size of the gap didn’t matter.

    It is important to stress at this point that we were dealing with compression rings that were brand new when fitted to the test engine.

    The gap was specially manufactured for the tests. So how come all oil burners and heavy breathers have ring gaps you can back a bus through? Well, the tangential load that the ring exerts onto the cylinder wall is a direct function of its radial thickness.

    As the periphery wears in contact with the bore, the radial thickness obviously decreases, as does the tangential load. Peripheral wear means a smaller ring o/d and this manifests itself as an increase in the ring gap.

    So, whilst all oil burners and heavy breathers have big ring gaps, it's not the gap but the reduced tangential load that is detrimental to the performance of the engine. The ring gap is a complete red herring.

    Imagine four top compression rings all with 1/16” gaps. The total gap for all four would be 1/4”. Now imagine the seal provided in an 80 mm diameter bore. Pi x Diameter = Circumference, so we have 3.14” x 3.15” = 9.891”. Multiply that by four cylinders and we have 39.564” – over a yard of contact seal between piston rings and bore. Now visualise the many litres of blow-by and consider whether all the gas is squeezing through 1/4” of total gaps or passing through 39½” of reduced pressure contact seal!

    But even this ignores one important facet of the argument because there is not just the one compression ring on a piston – there are usually at least two and that is because rings work as a team to form a labyrinth seal.

    **********
    For gaps to be the villain of the peace, the gas would have to find the gap in the top compression ring and pass through. It would then have to circulate to find the gap in the second ring and pass through that and so on. Now this may be possible if the power stroke lasts for 10 minutes but it doesn't, does it?
    **********
    At 3,000 rpm the power stroke duration is a mere 1/100second.

    Quite simply, the power stroke does not last long enough for the combustion gas to find its way around the maze – or labyrinth seal, so the villain of the peace has to be the reduced tangential load of the ring on the bore caused by peripheral wear or reduced radial thickness of the ring.

    This was our hypothesis based on the results obtained in the engine test cell but it took a very clever American to prove it. This genius invented telemetry that measured gas pressure between the piston rings in a working engine.

    Use of his brainchild revealed that some gas did get through the top ring gap sufficient to generate a hell of a pressure between the top and second rings – so it clearly was not finding the gap in the second ring. The labyrinth was working well. Caterpillar and IHC must have thought it was working too well because they increased some second ring gaps to 0.050” and 0.070” thought to be beneficial.

    Come to think of it, the exception proves the rule – as usual. Two stroke engines would not need stop pegs to prevent the end gap from crossing a port if the ring didn't rotate. The people who allege that ring gaps were not staggered when installed just because they are in line when the engine is dismantled don't need stop pegs.

    They could simply position the end gap away from the port and expect it to stay there – and we all know that this would get them into more hot water than a Yorkshireman’s tea bag! So why do they always blurt out their rubbish on the importance of staggering gaps?

    The very presence of a stop peg also proves my point about the size of ring gaps. Where a peg is fitted, the end gap has got to be 1/8” to accommodate the peg. There would be one hell of a draught through that if the 0.015”/0.018” boys were correct.

    This knowledge was commercial dynamite because, instead of the '0.015”/0.018” spec., it meant that new rings with gaps over 0.018” could be used without any detriment to the engine's performance. The gap was only detrimental when it was the result of peripheral wear. Customer acceptance was the only problem.

    To re-educate the customer would let the cat out of the bag, thereby losing the distinct commercial advantage. It was decided, therefore, to accept rings with gaps of up to 0.030” in a nominal bore but even then there were arguments. 0.030" in a nominal bore is 0.045” in a bore worn by 0.005” – and it's normally engines with this sort of wear that get new rings.

    The gaps on the new rings were bigger than the gaps on the ones being replaced which led to several heated conversations – and how the hell do you pacify the customer and keep the cat in the bag?

    It made diagnostics a lot harder too because when all rings set off in the 0.015”/0.018” area gaps of .040” meant something but now, when you don't know what they set off at, what they measure is meaningless.

    Well, now you know. All rings are free agents to rotate as they like, making staggering of gaps on installation a joke and ring gaps are not a problem provided that the gap is not the manifestation of reduced ring radial thickness caused by peripheral wear.

    In the light of the logic expressed in this article we are offering an expensive prize to anyone who gives us a good reason for staggering ring gaps on installation – a free burial at sea.

    M H Booth F.I.Diag.E

    CLICK HERE TO RETURN TO THE FIRST PAGE OF THE JOURNAL
     
  34. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    Fascinating. There's your convincing rationale for not going back in and "clocking" the rings.

    The only problem I have with that is the fact that the Yamaha factory service manuals specify "clocking" the rings. So while that may or may not be sound theory, I would do it because the book says to do it. As I've said many times before, I'm perfectly happy living under the (possibly rash) assumption that Yamaha, who built the bike, knew from whence they spoke.

    If the crack in the head leaks, take it somewhere and get it fixed. Based on where you say it is, doubtful anything will get warped.
     
  35. RickCoMatic

    RickCoMatic Well-Known Member

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    What cracked?
    An Anchor Point for the Cover?

    Get a Long Bolt with Matching threads.
    Grease the Bolt.
    Smear some Grease into the threads.
    WRAP the Bolt with 2 layers of Teflon Tape.

    Mix a small batch of JB-Weld.
    Fill the Hold and the Crack
    Place the ...
    >Greased ... taped ... Bolt into the Head and tighten the Bolt by hand.

    Remove ALL excess JB Weld from the Repaired area.
    Use a Razor Blade to "Clean-up" before the Mix cures.

    The CLEANED area should look like a "Finished" area with only the Product in the Repaired area, .... and a Greased, Teflon-taped Bolt remaining to be removed.

    Don't rush it.
    Let the Jb-Weld get as hard as, ... as, ... as a, ... as a rock!

    The NEXT day, ...
    Unscrew the Bolt.

    It should come out of that hole is was screwed into like a, ... like a, ... a, Popsicle does after 15-minutes outta the freezer.

    Pimp the repaired area.
    Carry-on.
     
  36. moellear

    moellear Member

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    Very Interesting Rick!! i like your idea on the fix and will be investigating the crack in more detail tomorrow morning. the small local Napa store has a shop setup in the back for all the local farmers and I'm sure they may have some ideas as well for the head. thanks again!!
     
  37. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    If you can get JBWeld into the crack effectively then this might actually be a good use for it.
     
  38. Robert

    Robert Active Member

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    I can appreciate the comments you published Rick, nicely written. I have always staggered the gaps as that is what I was taught some 30 years ago and most every manual I own echos this. It is also clear that the rings will go where they wish over time so I'm not arguing that. I would argue that the rotation is slight given the torsional forces that push the ring against the cylinder wall tend to keep it from rotating, or if it does, it would occur at a snails pace (realitive to the rpm, higher rpm...swifter march of the gap around the piston crown). There is the expectation that the gaps will at some point line up but it won't be for very long and the engine most likely will easily suffer this slight inefficiency with the existance of more cylinders. With thermal expansion, the ring gap should be minimal and preclude loads of blow-by so the gap issue is moot at temperature (IMHO) provided the gap is correct for ring type and bore.
    You pose a very good question publishing that article. I'm going to have to take a deeper look at this.
     
  39. moellear

    moellear Member

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    like the title states, NO START: the question I'd like to ask is why am I struggling? I feel there is not enough juice or something is going bad electrically

    got the crack repaired so back to getting it running now. I've had the battery on the 1amp charger all morning.

    didn't do much good so I changed it to 2amp, enough juice to hear the motor turn over but wouldn't fire. still got a clicking noise everynow and then. sometimes it would just be silent and not even turn.

    changed the battery tender to 40amp and boy thats enough to spin the starter (sometimes so fast I could hear brushes spinning or the starter gear spinning yet not fire). a few hits on the starter button and it fires up. after running 5 minutes or so til its warm and toasty/idleing smoothly, I turn it off.

    big mistake. it won't even fire up again when hot. WTH? the neutral light is very dim and things just tell me I'm not getting enough juice. I'm confused though... its a BRAND SPANKING NEW BATTERY. I plan to bring it back for a free testing at AutoZone today before heading to work, but any other suggestions? also how do you know if the solenoid is toast? a lot of times I hit the start button and it may attempt to start then just click click click really quickly around the battery area so is the solenoid bad?
     
  40. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    What did you do for the starter itself? Could need cleaning; might be the solenoid.

    When you get the "clicking" jump the big terminals on the solenoid (bypassing it) with a pair of pliers (shower of sparks alert!) and see if it then spins ok.
     
  41. moellear

    moellear Member

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    okay so if the pliers or screwdriver trick works then its (the solenoid) okay? i'm confused

    update: came back from a bicycle ride (great gas mileage there :) ) and touched the start button for the heck of it. first try it fires right up with a big surprise to me. tried it again and the battery just has enough juice to crank it. by the 3rd try it wouldn't budge or even try. like I said, taking the battery in for a checkup but I would swear its not the battery itself since it sat all afternoon without charging

    the starter: I just pulled it out to check the gears nothing out of the normal from what I could see. should I disassemble it for the heck of it? I'm thinking its something like the brushes but I don't know since I'm just a newbie to mechanics like this
     
  42. moellear

    moellear Member

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    the battery is fine. it holds charge all day and AutoZone still read 11.4 volts. I don't know where to begin... its always been stubborn to start but lately ever since my second upper engine re-assembly something isn't right upon firing it
     
  43. waldo

    waldo Member

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    Are you sure your battery is good? The guy at autozone once told me the lifetime warranty on my ceramic brake pads was not any good because the pads were worn out. Educate yourself on batteries here.
    http://www.dansmc.com/batteries.htm
     
  44. pirok

    pirok Member

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    11.4 V Hm! the battery is discharged or bad:
    (when i charge a new battery and its fully charged with the charger on (0.1 A) i got a reading > 13 V.)
    (charge the battery with max. 10% of AH ~ 12V14AH battery charge with max. 1.4 A)
     

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  45. moellear

    moellear Member

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    bike fired up again. got it warm, backed up out of the garage, thought I'd go around the driveway and crap it stalls. attempt to fire again; sound of silence... nothing. put 2amp battery charge on it and neutral green light is bright as can be. hit the start and it along with red oil level go dim each time motor tries to crank, with the 2amp charger on... leave it alone and green light is bright as can be though

    what's the deal? seems like something with a lot of power is required to crank it yet not being delivered properly. I don't know enough electrically to know what may be wrong... TCI, stator, starter, brushes, etc. 7 pages of my problem and I'm still bugging to get this fixed. definitely feel desperate guys, I'm losing it
     
  46. iwingameover

    iwingameover Active Member

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    Have a multimeter? I'd check the resistance in the wires from the solenoid to the starter and ground. You may have an interally corroded wire.

    More resistance means more power needed to do the same work.

    But it's just a shot int he dark and I don't know what the wire resistance should be.
     
  47. moellear

    moellear Member

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    plan to get a multimeter soon.

    I agree, it seems like there is resistance somewhere. could even be the battery. I'm leaning towards bad battery since now I can't even get it to crank without any 2amp charger. with the 2amp charger it will crank and that's it. the AutoZone manager tells me its a "good battery" after me telling him I purchased it from the same store 3 weeks ago...wonder what he would've said had I not told him that
     
  48. tskaz

    tskaz Active Member

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    That's why I stay the heck out of AutoZone. Just about any decent auto parts will be able to test the battery. Have it tested somewhere else and save the printout when they do it.

    If it shows bad on someone else's machine, take the battery back to AZ and demand (nicely at first) an exchange. If the counter clerk gives ya s**t then demand to talk to the manager.

    If it shows good on the other machine then you'll have to keep looking.

    But from a guy that sells batteries, it definitely sounds like a dead cell to me, and I'd exchange it just to make the customer happy.
     
  49. moellear

    moellear Member

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    battery issue?

    any thoughts? free night off work and since I can't ride thought I'd show what my problem is as well.
     
  50. SQLGuy

    SQLGuy Well-Known Member

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    Looks like a bad battery to me.

    Where did you have the charger clamps connected?

    One thing you could try to verify wiring is to run a jumper cable (as in the black pair of plugs from a car jumper cable set) from the battery (-) terminal to the engine. If it cranks then, then you've got a bad main ground wire or a loose negative terminal. If it doesn't then it's almost definitely the battery.
     

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