254xpg help please

[Welder56]

Did a complete rebuild on a 254xpg.

Did a vac and pressure test and had a base gasket leak. So fixed the leak and now it held vacuum for 5 mins without movement.

The tank vent is leaking (noticed yesterday)

My problem is when I start it I can get it to idle but on when at wot it takes some time for it to spin down after letting go on the trigger. Almost like a delay. Even if I blip it it takes time coming down.

I'm gonna check that I didnt put the diaphragms in wrong in the carb (checking that this afternoon)

Anybody else have any suggestions to check

 

[Yoopermike]

Sounds like its still sucking a little air. Did you spray the motor with starting fluid (carefully) to find any air leaks??

 

[Welder56]

No I didn't. I used water and soap while pressurizing.

That's what I thought as well. The saw is fighting me every step of the way LOL. Guess I'll have to check for leaks again.

Since it held vacuum for that period without I leak I figured it was solid

 

[Welder56]

Checked carb and i put it together right...

Pressure and vac test again. Came back solid. Not a hint of a leak even while turning it over.

So I'm thinking it's a fuel problem. Would tank vent do anything like this?

 

[Welder56]

On second thought... my flywheel has the key sheared off (from the original owner). Tried lining it up with some marks. Tourqed it down. It hasn't slipped but if I pull it wrong it tries to rip my fingers off.

Maybe I'm slightly out of time. Would this cause the WOT issues I'm having?

 

[Yoopermike]

Id fix that 1st before anything else! it might be torqued down but it very well can move on you!

 

[Chainsaw Jim]

Did you just clean the carb or rebuild it with a new kit?
Also...The throttle linkage could be sticky.

 

[Welder56]

I did check already if it moved and the lines are still lining up. But maybe I was slightly off to begin with.


I cleaned and rebuilt the carb with new kit

 

[kz1000]

Start simple and then go to the tough stuff. The 254 has the fuel line pass right next to the throttle linkage, Pull the top cover and make sure that the throttle linkage is returning proper and that the butterfly isn't a little loose or rubbing. Push the throttle closed with one finger while letting of the trigger.

 

[backhoelover]

the nozzle check valve (main jet) will cause it to do that

 

[Welder56]

Linkage seems to be returning without rubbing or chaffing anything. Will double check tomorrow. Going to a wedding tonight.

Now I have the fuel line grommet. Didn't wanna go in the hole at all. And it didn't have it in the tank to begin with. So I scratched it.

 

[cus_deluxe]

I cant see where excess fuel will cause it to race on after releasing throttle. Also sounds to me like linkage may be binding/worn.

 

[spindrift7mm]

Try vac/pres test with saw on it's nose just to rule out leak between oil tank and crankcase that oil will seal off until saw goes nose down or on it's side with gasket up. Found one last year that was a chronic leaker, now I end all my vac/pres tests in this position. Ken

 

[Agrarian]

the nozzle check valve (main jet) will cause it to do that

As hoelover said, if the main jet check valve is malfunctioning it can cause the saw to have trouble returning to idle. Did you blow the carb out with compressed air when you cleaned it? That is one of the main causes of the valve failing.

 

[Welder56]

Did not use compressed air to blow out the carb. Had it in a agitator (carb cleaner). Then sprayed it all out with an arisol carb cleaner.

 

[cobey]

It might be a wonkey carb.....

 

[Yoopermike]

Dont feel too bad, Im working on my 254 and it wont even fire!!! 130 comp, has fuel and has spark!

 

[Welder56]

Ahh not feeling bad. Just want to get the fine tuning details done with LOL.

Maybe I'll try replacing the carb then and see if it remedys the problem.

 

[Yoopermike]

Have any tricks on how to get the crank seal out of the holder by chance??

 

[Welder56]

I think I used a hammer and a small punch. Didn't go macho man on it. Just worked it out