[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/diy/ - Do It Yourself

View post   
File: 1.95 MB, 3264x2448, image.jpg [View same] [iqdb] [saucenao] [google]
1150091 No.1150091 [Reply] [Original]

I got a problematic ltz400. New plug, clean carb, clean air filter, valve lash within spec, 110 psi compression cold. It will start and run with very high idle,when you drop the idle engine dies(via throttle cable) starts back up when you adjust throttle cable again, pretty sure choke is shot but after its warm I should be able to get it to idle normally, it doesn't. Also it will rev without issue when you hit the throttle. Any ideas what I'm missing?

>> No.1150092

Non tps functioning diaphragm carb, timing is on and spark is good and consistent. Racking my head

>> No.1150093

>>1150091
you said you cleaned the carb. this sounds like an idle jet problem. if the idle jet is plugged you will have the issues you are describing. having it part throttle or hitting the throttle will utilize the main jet and would run.

>> No.1150286

>>1150093
Correct I cleaned the original jet that was a 25 on the pilot, small wire through it carb cleaner and 100 psi of compressed air, then changed it to factory 22.5 brand new. Also soaked and blew out all the vacuum air and fuel passages in the carb itself, I did the starter jet and main too. I'm gonna recheck valve lash tonight and perform a leak down test to see if I have a cupped valve maybe. Thanks for the reply anon

>> No.1150828

Check for vacuum leaks. Is the carb boot soft and supple? Compression is good and the symptoms do not fit valve problems.

>pretty sure choke is shot

I assume you mean enricher. If it runs better with enricher when warm that indicates lean mixture perhaps due to vacuum leak.

If it has a vacuum petcock, switch to prime position and plug the vacuum hose to the carb after making sure the hose itself is good.