97 GTX Hard starting

[willambs100]

Had new carbs on it, runs great wide open. After running it, you have to really crank it for it to "take off". It has lots of whitish smoke at first, then clears up and runs fine. It`s a 787 engine I believe. It runs good on top end, has an ever so slight hesitation at first, but jumps out of the water good after that split second. I`ve read through posts and here it is a crankshaft

 

[Bills86e]

Have you been doing the pre-ride dump out? Open the gas cap & get a Big ...Spew?

 

[willambs100]

not sure

Not sure about that. I just fill er up, and when it`s cold, it starts fairly easy, when it warms up, it`ll run like a top, idles good, but when you kill it, man you gotta crank it like crazy to get er running, and when it does, it`ll smoke heavy and sputter a bit, then it picks up and runs like a top again.

 

[Bills86e]

I bet plugs are wet

 

[willambs100]

reply

I checked them, they were dry. It fired right up, ran smooth, did have some white smoke at first, revved a few seconds and it ran like a top. this thing is driving me batty. When it gets hot, is when you have to crank it long to get it to fire, then it runs like at top. I`m curious as to what you meant about opening the gas cap and ......SPEW? My mechanic is prettty sharp and he`s a tad puzzled, he thought he`d see oil as well, but didn`t. They were dark, but not wet, they were dry looking with a tad of carbon build up and they were new plugs.

 

[Bills86e]

A large expell of pressure (spew) would indicate the tank relief check valve not
operating. At 3-5 lbs it vents any over-pressure under rub rail. It would force the carb needles open and leak fuel into cylinders and a hard start when hot occurs.
Plugs would appear wet, this is not the case as you stated they are dry. The rotary valve clearance is next major contributor to engines that are a hard start. Machining the cover back into spec cures this, as its the cover side that wears out. You could
try enrichening the low speed jet on each carg a 1/8th turn out (counter-clock wise)
and removeing the spark plug boots and trimming them 1/4", put boots back on, zip-
tie & dielectric grease them. These wire ends get burnt, so trimming helps. Reading your service manual will help you understand these issues. Bill

 

[willambs100]

thanks

So Bill, you don`t think oil leaking around the crankshaft seals when it gets hot would cause this hard start issue when it`s warm? I want to try and disspel that theory. It has new carbs, (or fairly new with carb kits installed), runs smooth and idles good as well, but when she`s warmed up, and you kill it, it`s a wench to try and start, you gotta get into the starte way too much and then it picks up, starts kinda rough, spits a little more whitish smoke, then runs like a top. I`ll read the manual, man I didn`t know the manual was that extensive where it would tell you tips like your telling me. I guess Bombardier has seen it all just about. you guys (Bill especially) are great to dumb butts like me. I know people give compliments and what not, but I don`t want it to go understated how much your perspective on things is appreciated. It takes time to type, get over your frustration with a dipstick like me, and keep trying to answer questions. so, I really appreciate the time your taking to assist me. Same goes for all the others out there. A big THANKS!!

 

[Bills86e]

Your post is most rewarding, just passing on the secrets!

People can get in a hurry for an answer, and not explain well or interested in how to
interprete the manual, or spellcheck their post. The manual is sometimes wrong too!

 

[willambs100]

so your not thinking the oil leaking when seals get hot theory?