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Discussion Starter · #1 ·
I have a 92 FXR (1340 Evo). Lots of battery power,proper voltage at coil,
plugs not fouled and sparking. Even changed ignition module. All wires I can see look good. Fuel getting to carb ok. Still wont start!
Any ideas would be appreciated.
 

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First of all, what happened when the engine quit? Did you just go out to start it, and it wouldn't start? Check to see if you have compression on both cylinders. You say you are getting fuel to the carb, but are you getting fuel to the combustion chambers where it is lit? Try squirting a little fuel into the carb throat with the throttle opened up. Close the throttle and try to start the bike. Are you sure the plugs are OK? Are there any backfires thru the carb or exhaust?
 

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Discussion Starter · #3 ·
When I parked the bike it was fine. Tried to start it a couple days later and no dice. No backfires at all.Plugs are brand new (tried 2 sets).I will try some fuel in the carb throat and see what happens. Not sure if fuel is getting from carb to chamber?
Thanks for your input!
Any other ideas would be [email protected]
 

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frankfrank said:
When I parked the bike it was fine. Tried to start it a couple days later and no dice. No backfires at all.Plugs are brand new (tried 2 sets).I will try some fuel in the carb throat and see what happens. Not sure if fuel is getting from carb to chamber?
Thanks for your input!
Any other ideas would be [email protected]
Sounds like you are on the right track. How long has it been parked? If it's been more than a couple months, you might have bad gas... change that first. Look into the intake and check to see if the valves are opening. I doubt that's it, but you should check everything that might be causing the problem. Is the spark good and hot (bright blue)? Could be a timing problem, too. It's odd that it showed no signs of failure before it happened..... :huh:
 

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back in 92 we saw a few where it ran fine untill parked would not restat where the pinion key failed and the cams ended up so far out of time the would not fire
 

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Otto said:
back in 92 we saw a few where it ran fine untill parked would not restat where the pinion key failed and the cams ended up so far out of time the would not fire
Yeah, that makes sense. :) Pull the cam cover and see what it looks like. Check for metal pieces in that area, too.
 

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Discussion Starter · #7 ·
Gonna pull the cam cover off tonite. Can't figure out where fuel under the
bike is coming from. After numerous attempts at firing it up, fuel ends up leaking.(black in color!) To cold up here to power wash it to see where it is coming from! I'm starting to get [email protected]
Thanx for the tips all! Any more ideas are greatly appreciated.

Frank
 

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frankfrank,
Before you tear into that thing, and because of what you have said, first try pulling both plugs and spinning the engine over with the starter while holding your finger over the spark plug hole. Do you have any compression? It could be that you have had a carb. leak spilling gas into the cylinders washing them down, or you have washed them down while trying to start it and have lost ring seal. If you have little or no compression, pour two or three ounces of motor oil in each cylinder and then turn the engine over by spinning the wheel while in high gear. After you have spun it a few turns, put the plugs back in and try to start it. This is of course assuming you have spark, fuel, and air.
 

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I agree with Roy, Don't go rippin' into things just yet. The fuel under the bike is probably coming from the over flow tube connected to the float bowl of the carb. If that is the case it could have fuel getting into the cylinders washing them down
 

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Haagdakta said:
I agree with Roy, Don't go rippin' into things just yet. The fuel under the bike is probably coming from the over flow tube connected to the float bowl of the carb. If that is the case it could have fuel getting into the cylinders washing them down
Yes, now that you mentioned the fuel leak (black????), determine what is causing that first. If the fuel is black, then it's either mixed with oil or carbon. Could be that you are leaking fuel into the engine cases and it's coming out somewhere. Drain your oil from the crankcase and smell it. If this is the case, then your needle/seat in the carb isn't closing. Make sure you always close the petcock to prevent that from happening. Don't trust those vacuum operated ones.

Check you engine case seams for leaks. No need to powerwash it. Just clean it the best you can by hand using some brake cleaner and a rag. When it's dry, you can dust suspected areas with talcum powder to make finding the leak easier.

It still wouldn't hurt to check under the cam cover. It only takes a minute to remove and will at least give you peace of mind knowing whether something is damaged or not. While you are in there, make sure the tappet lifter bearings are ok, too.

You might also have a bad intake leak. Maybe a gasket crapped out and it's sucking in too much air, then letting fuel leak out when you stop spinning it over.
 

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Discussion Starter · #11 ·
Thanks for all the input. Gonna explore some of those ideas tonite.
Compression seems good. Never tested but pulled the plugs and turned it over,
seems like the compression was good and strong. Got a feeling that the fuel is black because of oil in it. I always shut off the petcock when parked. If and when I would forget to do that it would backfire and run like **** till I blew it out. Any other ideas would be appreciated!

Frank
 

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frankfrank said:
Thanks for all the input. Gonna explore some of those ideas tonite.
Compression seems good. Never tested but pulled the plugs and turned it over,
seems like the compression was good and strong. Got a feeling that the fuel is black because of oil in it. I always shut off the petcock when parked. If and when I would forget to do that it would backfire and run like **** till I blew it out. Any other ideas would be appreciated!

Frank
OK, if there's fuel in the oil, then that's a sure sign that your needle and seat aren't seating. Time for a simple carb rebuild. That may solve your problems. By the way, the only way to get oil into the fuel would be to put in in the tank. It's usually fuel that gets into the oil. Since you are contaminating your oil, so it would be a good idea to change it after the carb work or you could damage you engine. Also, check your compression with a gauge. You simple can't tell if it's good by feeling the air blowing out. Compression gauges aren't expensive and your local Autozone can probably lend you one for free. You should be getting at least 120 psi with less than 10% difference between cylinders. Make sure you follow the instructions in the factory service manual when you do the check. There is a specific precedure you must follow to get the proper results.
 

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Discussion Starter · #13 ·
Ok an update.

I put a rubber ball hockey ball in the carb to form a tight seal.
Turned it over and bang. She fired right up.(even after being in a cold garage and not running for over 3 months). I suspect that means I have an air leak
somewhere. Only thing is once it starts it idles WAY to high. Have to shut
it down in seconds. Can that be the different ignition module I put in it not being compatable? I put a screaming eagle(8000 rpm) that was supposed to
be compatable. Or can that air problem be causing that?
Any ideas will be appreciated!

Frank
 

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frankfrank said:
Ok an update.

I put a rubber ball hockey ball in the carb to form a tight seal.
Turned it over and bang. She fired right up.(even after being in a cold garage and not running for over 3 months). I suspect that means I have an air leak
somewhere. Only thing is once it starts it idles WAY to high. Have to shut
it down in seconds. Can that be the different ignition module I put in it not being compatable? I put a screaming eagle(8000 rpm) that was supposed to
be compatable. Or can that air problem be causing that?
Any ideas will be appreciated!

Frank

That could also be an air leak leaning out the mixture.
 

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Y2K said:
That could also be an air leak leaning out the mixture.
I agree. The ignition module will not cause idle speed problems, but an air leak will. To check for the leak, start the engine and spray some WD-40 (using the 4 inch red "nozzle") that comes with the can, and spray it around anywhere there might be a leak. If the engine speed drops off slightly, then you have a leak. Some people use brake cleaner to raise the rpm, but that can be very dangerous since brake cleaner is VERY flammable! One mistake and you won't have any facial hair left (and maybe no skin left, either).

Remove your carb and intake manifold and replace the seals. When doing this, hold the intake against the heads without the gaskets first, to check alignment. The flanges should be flush with no large gaps. If there is a gap, you'll have to loosen the affected head and rotate it slightly so the intake will seal properly. I usually do this during assembly so I don't have to worry about it later.

One more thing.... make sure you tighten all the fasteners a little at a time during installation. If you completely tighten one flange first, then it might pull the others out of alignment. It's best to connect the intake to the heads BEFORE attaching the carb. That way you can look into the intake to check for gaps between the heads and manifold.

Once you get everything sealed up good and tight, throw it on a dyno and get it tuned properly. You should be ok after that. I'm still wondering about the black fuel, though. Oil should NOT be getting into your fuel. Maybe bad gas in the tank?????

Good luck! :thumbsup:
 
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