fed up with this bike

should I have cleaned anything in the pistons and needle thing? I didnt take those appart at all, all I did was polish the piston and put it back in. Also the piston in carb 3 doesnt spring back as fast as the others, it has a little drag. So I know I need to do something about that. But they all 4 passed the clunk test.

 

You really should polish (like 1000-1200 grit wet-or-dry "sandpaper") both the brass piston AND the bore hole in the carb body that the piston slides up and down in. The key word is "polish", you're not trying to remove material from either, just knock off any high spots and get them slicker than a baby's butt. Then they'll all clunk like a safe falling out of a 5th story window!

 

yeah, I use 1500 grit with WD-40 as the lubricant to polish the slides and bores. Works great. Don't forget to clean up the bores by blasting the WD-40 and sanding dirt away with carb cleaner.

 

Ok I finally got the carbs back together, cleaned, polished, new gaskets sealed to the bowls, and oiled. Mixture screws set, and Bench synced.
My drain screws are still stuck, but that will have to wait til next payday.
At least I dont have to pull the carbs to do that, Just the bowls.
(Hey look Im speaking your guys' language now, and I actually understand all this now. I came a long way, learned alot, cant thank you all enough. I wouldnt have got this far without you. And Speacial thanks to Rick, who was a super big help with this project).

Anyway, for now the carbs are all ready to go back on the bike today. (finally got a day off today to do this).

Wish me Luck!

 

Well I got the carbs on the bike. Bad news..

No fire..

Back to square one.

I diagnosed it and heres what I came up with

Spark: Good

Gas: Good

Air: Good

Compression: NONE

I pulled my vaccum line and tried to start it and there is ZERO vaccum there. I pulled the cap and checked all the vaccum ports on each manifold boot. NOTHING. So If my calculations are correct. there is no air flow to the engine, so that means gas is not getting to the engine because of it.

There was vaccum before. What happened?

Time to part this out or what?

 

Pull a spark plug and check for compression.
If there is no compression, pull the side cover and make sure the crank turns over. If not, check your starter motor clutch.
If the crank turns, pull the cam cover and watch to make sure the cams spin with the crank. If they are not, you got trouble. The cam chain may have jumped the gears (hopeful senario) or broken (not so good either but salvageable). Either case, you need to inspect the crank to make sure nothing got whacked. If the bits spin together, you probably have a hole in a piston or maybe two.
If you have compression and spark, you need to look at fuel, that is all there is to it. You could also have the spark plug wires mixed up or the connectors applied to the wrong coil, but there would still be something happening in the hole.
Let us know what you find out.

 

How did that happen?
Are you sure?
There's a difference between low and no compression.
NO Compression would have me checking the gauge!

Pull the Plugs and put a finger over a Sparl Plug hole.
If there's NO Compression ... you'll know. You'll feel it!

You didn't do anything to cause NO Compression ... did you?

 

Ok, Compression I got, Vaccum I dont. I put my finger over the plug hole, and cranked the starter, and I defineatly felt the commpression. I dont have a guage. There is no vaccum on the vaccum line or on any of the ports which have a plug over them (when I crank the starter) that I can feel.

Could it be:

Leaking intake boots?? they are cracked but the cracks dont go all the way through, they looked fine on the inside.

Bad Carbs?

I tried starting w/ petcock on Prime, RES and ON. No difference.

I am searching for my propane torch so I can shoot propane where the boots are to see if it seeps in through the leak (if there is one) and tries to fire.

 

It's possible, but unlikely ... that all four Manifolds are cracked so bad you got no vacuum.

Probe the nipples with a piece of line from a Weed-whacker. See if they are open or clogged.

PM'ing you.

 

um.....yeah. Do that. :!:

 

Probed the nipples in the manifold boots. Tried to fire but didnt. Still no vaccum on the line, or any other nipple.

 

Rick, Ok since we talked on the phone, I have good news and bad news. Good news is It does fire right up but it doesnt stay running for more than 5 to 10 seconds. It dies out and throttle and choke wont help. It does this no matter what the mixture screws are at, all closed, or carb one open a little. when it dies, I can fire it right back up but 5 to 10 seconds later it dies again. ant get it to stay running no matter what I do.

 

Next step is to determine if it's an electrical or fuel related problem.

I think its a Fuel Related problem.

What happens if you get it to run and leave the Petcock on PRIME?

 

same thing..

I tried that

 

Its definately fuel related because it acts like it just runs out of gas, even though there is plenty of gas in the tank.

also there is a delay when I open the throttle and when the engine reacts. It doesnt instantly rev up. and I have a little white smoke out the exaust when it does rev.

Does this tell you anything?

 

Sounds like maybe the petcock is cutting out, perhaps a tiny hole in the diaphram lets it shut itself off, or the fuel line is collapsing, etc.?

Maybe try using a separate fuel cannister (crefully) hooked directly to the fuel inlet pipe on the carbs, adn see if it keeps running. If it does, you've at least isolated the problem to the petcock or the tank.....

 

Energizer, what do your plugs look like after it runs? (wet/dry, oily/white)etc?

 

Its not the petcock because it flows constantly on prime. The carbs are getting gas, it runs when I shoot propane in the airbox, The plugs are dry and black but they have a few miles on them they are the same plugs that were in there before I cleaned the carbs. the mixture screws dont seem to change anything, sometimes it wont fire at all sometimes it runs for about 1 or 2 seconds and other times I get about 5 to 10 seconds out of it. But it always just dies out. What else would causer this problem?

 

The Ignition Module.
You might have a bad Module.
What's the number on it?

If you can get it to fire when you introduce Propane ... Put some Enrichment to it and see if it will run on Choke ... then, see if you can get it to run at higher rpm's by giving it some throttle!

 

Ok, it has a green label on it (I think thats the Ignition module: black box next to the thing with cooling fins on the left side of the bike under the side panel). The label reads:

IC Ignitor
Type TID14-08
5V2-10

and also stamped into the label is the number 109

How can I tell if this is in fact the problem, without buying another ignition module?

 

I thought I'd have a box that you could use to test it.
No Gots.

Put out an A-P-B and see is somebody's got one squirreled away.
Other than that ...
Call the Yammie Dealer and speak to the Lead Tech.
See if he has a Shop TEST one he'll loan you to see if your bike will fire.

I'll make a couple of inquiries about your situation with the Lead Tech at my Yam Dealership, tomorrow.

 

Thanks Rick, I pulled my TCI and I am inspecting the components, and solder joints. I am pretty good with a soldering iron, and pretty good at spotting troubles on a PCboard (I used to work on cell phones). So Hopefully I find something wrong in there, I already see a little corrosion on one of the contacts, so thats actually a good sign in this case. (means I might be closer to finding the problem) I will let you all know what I come up with.

 

I didn't see anything in this thread about carb synching? I used to have a similar problem. Bike would start run for a few seconds and then die. If I tried the throttle at all in those few seconds - die. A combination synch and colourtune fixed me.

So question is - have you done a carb synch? Are the mixture screws about 2 turns out?

 

The only sync I have done is a bench sync so, I believe it is in the ballbark. and the mixture screws, I've tried 2 out, 2.5 out, 3 out, all closed, all closed except carb one at different lengths. All have the same result.

Also it is not an instant "kill switch" type of die. It is a "SLOW" Die, but doesnt sputter out. just slowly loses RPM until dead (best way I can describe it).

 

That sound like Fuel Starvation. Not electrical or Ignition related.
Did you pull the Float Valve Bodies and Clean the "Beenie-Screen's"?

Even if the Petcock was brand new ... If there's particulate fouling the Float Screens ... Gas won't get into the Carbs fast enough to keep it running.

 

How long has it been sitting. Starting to wonder if it might have stuck rings on the piston that is not sealing. But gives enough compression for the propane but not the fuel. Just thinking outloud since I do not know if propane requires lower , higher or the same compression as Gasoline?
Only reason why I say this is years ago I had a FT500 Ascot that had gas, spark and felt like good compression when I put my finger over the sparkplug hole. Well it was some compression but not enough and it never did run until I removed the cylinder and put some mystery oil on the rings.

Sean

 

Just curious, did you try replacing the fuel line between the petcock and the carburetors?

EDIT:

I seem to remember a story years ago about a plane with the same maddening tendency to run well and poorly unpredictably. It turned out that there was crud sloshing around inside the tank that would block and unblock the fuel outlet, leading to poor running conditions that were very hard to diagnose. I believe it was leaves in the tank or something.

 

yeah Fuel line is new, along with the fuel filter, and yeah Rick the beanie screens are clean, I shot cleaner through each one and can see that they are clean holding them up to the light. The bike has not been sitting very long this time, when I bought the bike a few months ago it fired up everytime, It was rode 85 miles to my home town from where I bought it, It did great. This problem started after I got it home.

 

If my ignition module was bad, would I still get good spark?

 

Maybe intermittently. But, I doubt that that is it. It wouldn't slow quit. It would shut down and be dead.

Somewhere along the line you aren't getting a normal fuel supply ... or, so it seems to me. The fade-out is the key. Running out of gas.

Check the vacuum line from the Intake Manifold to the Petcock. Make sure it's really vacuum line. Move it to another Intake Manifold. Maybe you have a burned valve or a tight one and you aren't getting good vacuum on that line.

I wish I was closer to where you live. I'd like to spend the day with you and the bike. We are getting close to the point where needing to inspect the bike and do hands-on troubleshooting is necessary.

Keep the faith.
We'll get it.

 

can't you check for fuel problems by taking the tank/petcock assembly out of the equation and use an auxilliary gas source?

When i sync'd my carbs for the first time with the tank off, i just used an empty water bottle with some fuel line submerged, made sure the bottom of the line was higher than the top of the carbs, and gave it a little suck to get it going (you just have to suck it so the level is lower than the bottom of the submerged part of the fuel line, not into your mouth..)

Then just hold the line and install it directly to the carbs.... wait a couple minutes, and unscrew the carb drain screws on all the carbs to make sure there is fuel in the bowls.

use some ether or propane to make sure it gets started, start out with a ballpark setting on the mixture screws, back off the idle screw a good bit, give it some choke. maybe trickle charge the battery for a couple hours before hand so everything is stacked in your favor.

if it runs then... you know where to look
if it doesn't, you can at least start eliminating possibilities.

all it takes is a couple feet of fuel line and a container....

 

yeah, I'm starting to think the petcock is not supplying the proper fuel. take it out of the equation as described above. If it runs on a bottle of fuel, your c*ck is not being suc...umm your gas valve is not functioning properly.

 

I have tried the petcock on prime and it flows fuel constantly wouldnt that be the same thing as an alternate fuel container?

 

are your drain screws frozen? or can you get em out? If it flows freely on prime, then set it to prime and make sure that each carb drains when the screw is loosened. even IF there is a tank/petcock problem, if there is fuel in the bowls, it should start and run for a couple minutes. Rather than wondering what the problem could be, it might be easier to start eliminating things....

trying to start a non running bike is hell on a battery, especially after this long. You might pull that battery and hook in a car battery or something because a weak battery, even though it might turn the engine over, might not be giving you enough steady power to give consistent spark.

It took me an hour to start my bike for the first time, after the old battery had been on a trickle charger until it read full. the plugs were all sparking (though not super strongly.) I replaced the battery with a new properly charged one, and it started on the first turn. The only problem was the battery.

i forget what the procedure is for using a car battery, but i'm pretty sure you have to take the smaller bike battery out of the loop....check that with a search first though.....

if i'm not mistaken, at idle, the battery is still supplying most of the spark, you have to be above a certain rpm for the generator to kick in and start providing enough power to charge the battery and spark at the same time. If this is true, a weak battery would continue to be a problem even if you can get it to idle for a couple seconds.

either way, checking for fuel in the bowls (checking fuel level would probably be even better.) and using a known good fully charged battery will start eliminating possible problems.

 

Yes. That would do the trick.

OK ... some of the reasons a bike won't start after a Carb Cleaning.

Pilot Screw O-rings not seated. Crushed or tilted. Not below flat washer.
Main AIR and Pilot AIR Jets swapped of position. (Haynes misprint)
Float Valve Screens
Diaphragms not seated. Major Air Leak.
Float Heights way off (Low)
Diaphragm Pistons Sticking
Air Bound Inline Fuel Filter (Acts like Vapor Lock)
Kinked Fuel Line
Pinched Fuel Line
Inline Filter on backward
Pilot Jet AIR Passages clogged.
Pilot Jets Clogged
Wrong Fuel (2-stroke not straight gas)
Bad Fuel (too old)
Wrong Jets (Swapped - Hitachi) <~~ (This needs to be investigated)
Float Valve Pins Stuck
Carbs way out of Sync and Pilot Screws way out of adjustment.

 

It's nice to have you on the case, Kellen ... you're throwing strikes!
Good work.

 

OK i just re-read the full thread.

it hasn't run properly since you rebuild and replaced the carbs.

before that it was intermittent.

so something is going down in the carbs.

When you bench synced the carbs, did you leave the butterflies open, or are they close to all the way closed? After my bench sync, they were still pretty far off once on the bike. try starting at WOT after checking on the battery situation.

You really need to find out if fuel is in your bowls though, and at what level.

If you can't get your drain screws open, then pull the entire bowl off. Messy, but at least you'll know for sure that you have gas. Or better yet, pull the carbs off the bike again (once you've done it once it only take a couple minutes...)and turn them upside down. You should get a couple of cups of fuel pouring out (don't do this over your lawn.)

Just getting gas to the top of the carb isn't enough, you need it in the bowls at the bottom, and for that, the fuel needs to get past the mesh screen that your float needles are possibly stuck in. (maybe after reassembly, you stored the carbs upside down for a few minutes and the neoprene needles froze into their seats.

When you cleaned the carbs, did you pull the seats out and get them zestfully clean?

After reading the whole post, i'm still thinking its fuel, but with stuck drain screws, its hard to check without pulling the carbs off.

I think this is actually good news, because its far more likely to be fuel than expensive ignition components.

an hour with a torch, hammer, screw driver and some unkind words should get those drain screws out.

 

Jumping from a car battery.

#

Attach the cables in the following order:

1. Attach one end of one cable to the Bikes battery's positive terminal.
2. Attach the other end of the same cable to the positive terminal of the battery in the starting vehicle. MOTOR NOT RUNNING!
3. Attach one end of the other cable to the negative terminal of the battery in the starting vehicle.
4. Attach the other end of that cable to the engine block of the bike with the dead battery. Look for unpainted metal surfaces and be sure it will clear anything moving when the bike starts. Do not attach the negative cable to the Bike's battery itself.

Before you do this. Be sure that the water level in the battery is checked and the Vent Hose is connected.

 

The Handy-Dandy SEARS Hand-Held Impact tool will get those Drain Screws OUT!

Get the Bowls off the carbs.
Oil them with Vegetable Oil
Heat them with a Propane Torch
Assistant wearing gloves holds Float Bowl
Use SEARS Impact Tool.
Apply initial turning torque.
Add Impact ... (Smack the tool sharply)
Screw breaks free and is extracted.

http://www.sears.com/shc/s/p_10153_1260 ... act+driver

 

I'm placing my bet.

 

Yeah first thing I did when diagnosing this problem (so I would get pretty much unlimited starts out of it) was hook the bike up to a spare car battery with cables. the car battery is inside an empty 5 gallon paint bucket so it is not sitting on concrete. the positive cable is hooked direct positive to positive. the negative cable is hooked negative to the main groung lug on the bike frame down by where the clutch cable ends. The starter cranks at full power, so no problem there.

I bench synced using a paper clip: set number 3 to the clip with the idle adjustment screw, then synced the pairs until all 4 were exctly the same.

and I did store the carbs upside down for awhile. But I had all the parts from the carbs removed when they were.

Im not sure what the seats are I think you are refering to the part with the screen on it that the little needle with the rubber tip goes in to. Yes I pulled those all off and cleaned them super good.

I am 99.9% positive that gas IS getting to the bowls. When I pulled the carbs off to clean them there was gas in the bowls then. And I shot cleaner through passages and it flowed in to all 4 ports going to the bowls. I will pull a bowl off and see if there is gas in there now. I need to unfreeze those drain screws so we can check float levels. But for now we will see if there gas in there.

 

Yep, that's what I always say. Might be a piece of junk left in the carbs that's clogging the fuel inlets....had that happen to me on my very first carb rebuild. "Halfway" cleaning carbs tends to loosen up a lot of junk that remains inside, and then starts clogging up your newly "cleaned" carbs.........

 

This bike starts then "slowly dies out".

4 carbs slowly dying out - not likely.

Bowls filling slowly. Bike starts after sitting a bit, sucks them dry, dies.

4 needles and seats all screwed up the same (not likely) or fuel not getting to the carbs fast enough (BINGO!).

This problem will be found between the fuel tank and the fuel inlet on the carbs.

 

Oh, you're going to hit a dead end soon with those drain screws.

Order up a set of replacements from Chacal.

You'll need them to set your float levels.

 

it starts and slowly dies out when loaded up with propane...

propane starts, runs out, engine dies. i guess it depends on where the propane is put, but if its in the airbox, it would last for a couple seconds...

seems to me that no gas is getting into the carbs. but i'm probably wrong. might as well test it though. if the bowls were full, it would run for more than a couple seconds right?

 

I'm thinking more like Reversed Fuel Jets.

Ran and then dies.
If the Fuel IS there ... Once the Supplied Amount of Fuel is depleted it dies.
Can't get the Pilot Mixture right ... even with the Screw CLOSED!

So, we got to go back in ... no matter what and see.
While we're in there ... we get the Drain Screws loose.
Do a real Float Level Set.
Put 'em back on Set-up and ready for Tweaking.

Do the Bench Sync like this:

Cut strips of Business Card 1/4" wide.
Slip a strip under the Butterfly of No.-3 and get the good drag going.
Leave the strip under No.-3
Next ... put a strip under No.-4 and match the drag on No.-3
Then, ... get No.-1 & No.-2 together and match No.-2 -to- No.-3
Bingo.
Bench Sync.

Now, ... Index the top of the Pilot Screw Hole.
With all 4 Screws Bottomed Out ... Permanently mark the outside diameter around the screw hole ... matching the orientation of the Screw slot when closed.
4 marks ... 0, 1/4, 1/2, 3/4 ... so you know the orientation of the screw without having to guess-tim-ate!

After Bench Syncing the Carbs ... Pre-set the Pilot Mixture Screws to the spot between 2-3/4 and 3. Splitting the difference between 2-3/4 and 3 ... Presetting the Pilot Mixture Screws to 2-3/8th ... Not quite 3!

Button-up that Puppy and fire that mother up!

 

IF you will look at my post on page 5, I asked what your plugs look like.

If they indeed are wet from tryiong to start that would tell you if you are getting fuel.

If they are still pretty and dry then chances are your not getting any fuel.

When you have a problem one of the 1st things you should do is check out those spark plugs. (they give you clues if you know how to read them)

The 2nd thing is to check those exhaust head pipes and see if they are equally as hot if one is cold... you aren't firing on that hole.

The next thing is to check for compression, (no guage, use your thumb over the plug hole) They should all be about even in respect for compression.

Use your senses (all 5, touch, smell, sight, hearing, I don't recomend tasting stuff though) when you are trouble shooting.


Sooty black plugs = bad combustion.
Clean dry plugs = no fuel, it's that simple.

Want to know how to read plugs? Just get any repair manual, it's in there!

 

Plug read chart:

http://www.verrill.com/moto/sellingguid ... rchart.htm

 

Ok, I bypassed the whole gas tank and petcock by hooking up a red plastic gas can with fuel line directly to the carbs, carbs are getting gas, I saw the gas flow in to the carbs. Still no start. Sprayed Starting fluid in to the air box, fired up for a second and died. Pulled a plug. Plug has a good nestle chocolate look with a tad of carbon build up. and PLUGS ARE WET. So I am getting fuel to the plugs, But still not starting. Whats up with that? Weak spark?

 

just getting fuel through the carbs doesn't mean that its going to be a correct enough air/fuel ratio to burn... rick suggested the air and main jets being swapped...? I'm not sure about this because i have Mikunis, and they have different thread sizes so can't be swapped, but i imagine that this would result in a very off air/fuel ratio. I don't know what the chances would be of doing it to all the carbs though....

maybe new plugs? I'm not sure wet nestle chocolate is the best look for a spark plug, but i guess if it fires then it fires...