starting problem-please help

[1998yamahawarrior]

ill try those ideas in the morning. ive been getting spark but it seems like its sparking at the wrong time because it is back firing out of the carb and exhaust really loud. the charging coils are measuring at 1.0 ohms. the new pickup coil is testing in the range that it needs to be. i hope those ideas work. thanx and ill let ya know.

 

[1998yamahawarrior]

well i tried those ideas , they didnt work but i decided to test the ignition coil and the primary is testing double what it is supposed to read in ohms. it is sparking though, so would that cause a weaker spark?

 

[yamarider]

I'm thinking that it might not be firing at the right time, like you said. If it backfired and the flywheel key sheered the timing will not be right, it'll make spark but it'll be wherever the flywheel is misaligned at.

 

[1998yamahawarrior]

will the timing marks still line up because they do.

 

[1998yamahawarrior]

well since the primary ignition coil was testing out of spec i decide to get one and hope thats whats wrong because i went to the local shop and one of the guys siad weak spark would cause it to backfire the way it is so. im crossing my fingers , cant wait til it gets here.

 

[1998yamahawarrior]

well she fired right up but then i shut it down to put the air cleaner back on and now im not getting any spark so its time to check coils agian

 

[sykowarrior357]

damn wtf...something has to be wrong...sounds kinda fishy...like the wiring harness is screwed up to be causing these crazy problems like that.

 

[1998yamahawarrior]

well im gettin spark agian the pickup coil wire slipped out from the holder and the flywheel cut it,so i wired it back together and its fine still tests within limits. it fired twice agian today starting fliud, kinda ran shitty and wanted to die, and warm up but onces its warm it wont fire. a friend that works on yamahas all the time, i told him what it was doing and whats been replaced. hes pretty sure it sounds like the cdi is in the proccess of going out completely, but i need to compare the spark to see if it is acually sparking enough. What do you guys think.

 

[boxhead]

The problem may not be electrical, I would take a good look at the head components. I would check the cam, rockers, or valves for scoring or any form of damage. A compression test will tell how the valves are, and you should be able to investigate the rest with a flashlight through the valve lash openings. A bad intake valve would certainly cause the backfire. Have you installed a aftermarket cam or springs, or floated the valves on accident before? This might be a combination of problems with electric and the mechanical components in the head. Perhaps a problem with one influenced the other... I've seen one of the rockers seize in the head before and hold a valve slightly open. Check the cam chain stretch also.

 

[1998yamahawarrior]

the head was worked on this spring by a local engine shop, when i put the piston in. i probably have about 5 hours of riding since then. also when this started we investigated all the head components first because i was afriad something broke (the way my luck goes i thought the worst).
it all looked good and compression wise i can hear it threw the exhaust when it goes threw the exhaust stroke. the cam chain is far from loose. it is getting spark but it does not look like its a strong enough spark. especailly since it will only ignite the starting fliud once in a while. everything thats testable is checking out know so that part of the resaon im leanning towards the cdi. Sorry this is so long.

 

[boxhead]

It's gotta be, or something retarded like a bad wire. That's about how my luck goes

 

[1998yamahawarrior]

ya i know how u feel

 

[1998yamahawarrior]

well im good togo now, i decided to start looking over the grounds. the main one to the block was good. the little wire that comes off the main wire and goes into the harness on mine has a quick connect on it, i went to pull it apart to check how it looked inside and the one end busted off so i just wired it up and tried it and she fired right off with no hesitation. i guess the aftermarket cdi can wait til taxes next year now. Thanx for all your help and ideas.

 

[boxhead]

I had a situation where every time I went through a puddle the rev limiter would come on from the parking brake removal. I knew what it was, but still had to get back to camp with it doing that every couple of minutes.