Top end rebuild (Stuttering, Elec. Issues Prior) (Pic heavy)

Re: I need your brains

KA1J, I eliminated any chance of tube-kinkage when I put in the new lines. The original fuel tubing was arranged in a way that certain points of the tube could have bent over on itself, but the tube was so old it was pretty much "baked" into a certain shape. Or maybe that's the way it comes from the factory? Regardless, I put in the new lines with kink-proof tube in a kink-proof fashion. Refer to my unnecessary drawing below.

Ground-Hugger, I did try that at a point, but to no avail.



I need to fix the charging system before I take it out on the road anymore -- just to eliminate that possibility. Also going to check the color of the plugs one more time to see what last night's ride did to them.

 

Re: I need your brains

Have you considered your TCI module? The ignition timing is controlled by it and you could have an intermittent going on with a bad solder joint or a dried out electrolytic capacitor. From your diagnosis, it sounds like the problem occurs under acceleration and therefore could be timing related? Sounds like you've gone over the fuel delivery so maybe the problem is electrical, just a guess...

 

Re: I need your brains

and of course there is no way your fuel filter is connected backwards

 

Re: I need your brains

STUMPED

Plug chopped again, and I've never seen a plug like this before. On one plug, half of the tip was white-ish, half was sooty. :?

Last things I've done:

- My stator coil was OHMing out of spec, new (used) one came in today

- Replaced the battery

- Reset the cam chain tensioner

The CDI module is the next thing I'm going to try. Even used they are pretty pricey. But there's no way to test the darn thing other than trying another one.

Correct, they were kind enough to put a "flow arrow" on it

 

Re: I need your brains

white tipped carbon dusted plug. Doesn't that fit in with your theory of the engine starving out at high speed? Just for the hell of it - remove your fuel filter and try to have your fuel line's curves as subtle as possible. It doesn't cost anything, it's an easy job and it will at least eliminate another possibility. I installed a fuel filter early in the spring because I only had the one in the tank. First ride - engine starved out. The line must have kinked just enough to restrict the flow. I removed the filter - no more problem.

 

Re: I need your brains

I'm following your post because I think I have your exact same problem on my 86 maxim x 700. A lot of the people I spoke with said they had a similar issue that was fixed after they replaced the stator. How is your issue now after replacing it? Have you replaced the regulator/rectifier as well?

 

Re: I need your brains

The gas ate through the plastic on my fuel filter, so it looks like I'll be trying your suggestion while a metal one comes. I wish that could have been the problem, but the bike started acting up before I changed anything in the fuel lines.

I put in a new stator and I'm waiting for a new regulator/rectifier to come, and then we'll see what happens. My manual doesn't give any test reccomendations for the regulator, it just says "try everything else first and if your voltage at the battery is too high or low, replace the regulator/rectifier."

Good to see another GA local, too.

 

Re: I need your brains

Wow! The gas ate the fuel filter??? NOT normal, that could be part of the problem. Did you get an automotive/motorcycle filter? REALLY odd that is.
Voltage regulators are not hard to test, just look at the voltage from idle through 3000 rpm. If the voltage doesn't rise from static above 2500 rpm (or thereabouts) you either have bad brushes or the regulator isn't happy. Check all connections and ohm out the lines. If all else fails, I would agree the regulator is at fault.

 

Re: I need your brains

Yea I've never seen that before on a fuel filter. I thought maybe it had melted somehow when I first looked at it, but I hadn't run the bike for two days and the plastic was cold but goopy.

I think I posted the numbers before, but when I have the multimeter on the battery, it's at 12.5v at idle and only rises to 12.7-8v at 5k rpm, whereas the manual specifies somewhere around 14.5v when things are as they should be.

The stator lines OHMed just slightly out of spec, but even that can be kind of misleading because a stator with in spec wires could have bad brushes (like you said). I found a good used stator from an earlier model XJ, and it OHMed in spec, plus the brushes looked alot better.

Just waiting on the regulator to come and we'll see what happens.

 

Re: I need your brains

Have you checked the vent on the gas tank? Could be stopped up preventing fuel from entering the carbs

 

Re: I need your brains

Yea, BigFitz mentioned that before. I took the entire thing apart and no one told me it had a zillion little parts to hold the key flap closed, lol. Luckily I tracked down all the parts that flew off.

 

Re: I need your brains

- Removed fuel filter

- New fuel pump

- New stator

No change in performance. Regulator/rectifier still inbound.

 

Re: I need your brains

Is your bike losing power when it sputters? Gauges and headlight flash and almost go out. Mine was and after opening up the cluster I saw that my ignition switch was damaged by PO and it was very loose and hardly making a connection. I repaired tonight so hopefully it will be fixed tmo when I go for a test run.

 

Re: I need your brains

hahaha i thought i was the only one... turned out to be that i was setting the float heights using a gas-resistant ruler which had 1/16" marks on one side and 1/32" marks on the other--which i mistakenly mistook as mms. big duh moment.

coils can be intermittent under certain conditions; they'll ohm out ok, but when they get hot, or vibrate at the right frequency, they'll open circut... which seems consistent with this only occurring below 5k rpm. but then again, you had 4 white plugs when you chopped. so hmmmmmmmm....

i cant remember if you said you changed your plugs or not. whenever i have a bizarre running issue that completely stumps me, 6 times out of 7, changing the (seemingly fine) plugs will do the trick. definitely try replacing them if you havent (cant hurt).

does this only happen when you snap the throttle open fast? and/or does it happen when easing it (more) open? does it do it in neutral? or only under load? is it worsening? your battery sounds sad. i would have tried a different/new one before the stator coil. like sh!t gets all in the bottom and starts to short it out. its a long-shot but, maybe, when you accelerate, the crap in the bottom moves towards the rear and shorts out a few cells. but it doesnt do it at high revs. so hmmmm. you got a real stumper there... sorry man i know how you feel. all like: 'i know my sh!t, ive fixed every issue that this bike has thrown at me, big or small... this should be easy I SHOULD KNOW WHATS WRONG!' and then you sit there and you feel like the solution is about to pop into your head, but it doesnt. so then youre all 'well if i just go through the carbs one last time then maybe ill see something ive overlooked'. and they're all spotless and perfect and just like new, just like how they were when you just put them on last. (well perfect except for that one jet that the PO kinda gnarled-up)
well maybe i cant speak for you but thats how i would be feeling. at least its not that feeling where you know which part needs to be replaced, but its the most expensive one on the entire bike. or is located deep in the bowls of the engine and requires much disassembly and new gaskets and labeled tupperwares.

i would save the CDI till last. im thinking no on that being the cause. or maybe theres a loose connection/broken wire somewhere around there that vibrates just right, or moves when you accelerate just right... as someone said, check the ignition switch. mine cuts in and out sometimes too. is there a magic rpm where the whole bike acts up? maybe, given your speed limits and gear changing habits, you happen to only cross that rpm while accelerating? also check your battery posts (or whatever they're called). i had too long of bolts in there once, so i thought i was getting it tight, but the bolt was running into the battery a little and was constantly vibrating loose and would cause crazy intermittent power loss. (more random tho).

anyways... good luck with your heavy burtation, im interested to know how you finally resolve this.

 

Re: I need your brains

hahaha i thought i was the only one... turned out to be that i was setting the float heights using a gas-resistant ruler which had 1/16" marks on one side and 1/32" marks on the other--which i mistakenly mistook as mms. big duh moment.

Yep, I checked em again and again...I could do it blindfolded with one hand!

coils can be intermittent under certain conditions; they'll ohm out ok, but when they get hot, or vibrate at the right frequency, they'll open circut... which seems consistent with this only occurring below 5k rpm. but then again, you had 4 white plugs when you chopped. so hmmmmmmmm....

Someone was parting out a Seca II the other day and I got him to send me both coils. I'll try them once the get here. That does make sense, because the problem does get worse as the bike warms up. If I was running lean, I'd figure that would be the opposite -- as the bike warms up it'd need less fuel...and the plugs were white that one time. After trying it again later there were spots of soot.

i cant remember if you said you changed your plugs or not. whenever i have a bizarre running issue that completely stumps me, 6 times out of 7, changing the (seemingly fine) plugs will do the trick. definitely try replacing them if you havent (cant hurt).

Yep, I've definitely made NGK rich through this process lol

does this only happen when you snap the throttle open fast? and/or does it happen when easing it (more) open? does it do it in neutral? or only under load? is it worsening? your battery sounds sad. i would have tried a different/new one before the stator coil. like sh!t gets all in the bottom and starts to short it out. its a long-shot but, maybe, when you accelerate, the crap in the bottom moves towards the rear and shorts out a few cells. but it doesnt do it at high revs.

During the first 10-15 minutes of riding, it will only hesitate when you snap the throttle fast. After that, any acceleration and it will stutter -- and I wish I could get people to ride it to see what I mean -- but it's a sharp stutter. Not just a feeling like I'm losing power, but it's like all the sudden the cylinders are fighting against each other. Then I'll give it MORE gas and it will stutter less and start to accelerate.

I did try a difference battery before I put the new stator in there. Same result, as far as what the multimeter told me.

so hmmmm. you got a real stumper there... sorry man i know how you feel. all like: 'i know my sh!t, ive fixed every issue that this bike has thrown at me, big or small... this should be easy I SHOULD KNOW WHATS WRONG!' and then you sit there and you feel like the solution is about to pop into your head, but it doesnt. so then youre all 'well if i just go through the carbs one last time then maybe ill see something ive overlooked'. and they're all spotless and perfect and just like new, just like how they were when you just put them on last. (well perfect except for that one jet that the PO kinda gnarled-up)
well maybe i cant speak for you but thats how i would be feeling. at least its not that feeling where you know which part needs to be replaced, but its the most expensive one on the entire bike. or is located deep in the bowls of the engine and requires much disassembly and new gaskets and labeled tupperwares.


Can't tell ya how many times this week I said I was giving up! But the problem is there, and something is causing it, and I will find it. When or how, I don't know lol.

i would save the CDI till last. im thinking no on that being the cause. or maybe theres a loose connection/broken wire somewhere around there that vibrates just right, or moves when you accelerate just right... as someone said, check the ignition switch. mine cuts in and out sometimes too. is there a magic rpm where the whole bike acts up? maybe, given your speed limits and gear changing habits, you happen to only cross that rpm while accelerating? also check your battery posts (or whatever they're called). i had too long of bolts in there once, so i thought i was getting it tight, but the bolt was running into the battery a little and was constantly vibrating loose and would cause crazy intermittent power loss. (more random tho).

Good ideas, I will check the electricals on the handlebars. It does the acceleration stutter between 4k-5.5k RPM, and that's where the bike has the most vibration anyways. It's very consistent, if there was a loose connector/wire somewhere, you are right that it would be more random. Plus the way it gets worse when the bike warms up tell me it's something else, too. But I will check those things because I never have before.

anyways... good luck with your heavy burtation, im interested to know how you finally resolve this.

My bike is running as smooth as her news report!

 

Re: I need your brains

Are you sure they were spots of soot? I hope so. Running too lean under load starts burning the aluminum of the cylinder head. The effect on the plugs is little specs of burned aluminum.

 

Re: I need your brains

oh man oh man oh man. emulsion tubes! check to see if they're ovaling out: (the thing the needle slides into, with all the holes in the sides and jet at the bottom). the orafice that the needle slides into should be round, not oval. check out this link. secondish picture from the top. but then again.... white plugs.... im sure too that the holes in the bottom of the bowls are all free and clear?

o wait i think i may have just found out what it is... from this thread

haha, "umpteenth"
i found that thread searching for emulsion tubes haha.
so do i win the prize? (lol what was it i said about coils, again...)

 

Re: I need your brains

Yeeaa I thought the same thing, but it wipes off with a finger swipe and it very fine like soot.

Oooo, some helpful threads, thanks for pulling them up. I'll check the emulsion tubes and see how they are. I mean, I always clean them and polish them and hold them and caress them, but I'll check for ovalation this time.

Same with the pickup coil, it's just one of those things I would have never checked. It shall be inspected as well.

The coils come tomorrow -- should have some results of SOME KIND by the end of the day. Oh boy!

 

Re: I need your brains

Nothing new, just a quick video status update:

[flash=425,355]http://www.youtube.com/v/uK7c8Djm8eQ.swf[/flash]

 

Re: I need your brains

Put in the new coils, new plugs -- same result. Stutters sharply under acceleration and worsens as the bike warms. Although with the new coils, it eliminated a vibration around 4k RPM, and it revs alot smoother. Odd.

Nothing I've done since the beginning of May has had any effect on the stuttering problem, though. Not even the slightest bit. Exact same. What demon lurks inside there!?

Recap of what I've done since May 4th:

- New air filter

- Changed the oil

- Changed the plugs (5.25.2011)

- Put the valves in spec

- Cleaned the carbs x92

- Set the floats

- Adjusted the carbs with a Colortune

- Synced the carbs

- Rebuilt the clutch

- Checked all vaccuum hoses/boots

- Replaced stator

- Replaced rectifier/regulator

- Replaced both coils

- Tested pickup coil

- New exhaust gaskets

- New fuel pump/lines

- New battery