The 460 I've got is not wanting to come back down to idle when revved or cutting and you let off. It ran fine one day put it up and the next time I tried to run it this started. I've adjusted the carb everyway I can think of. It isn't ported just a dual port muffler. The high limiter is gone, and the low is still there. It runs just fine and the plug still has good color. It will start when warm and idle fine without using the high idle. I pulled the carb off and checked the boot and couldn't find anything wrong with it. It doesn't matter which way the saw is either, on each side or straight up or down it still does it. I don't have stuff to pressure and vac test so that is out for right now. I'm boxing up tools to move by the end of next week so I won't mess with it much unless someone has some simple things to try.
Ms460
- Thread starter mdavlee
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Brian13
Addicted to ArboristSite
This is real simple and you might have already thought of it but is the throttle sticking on the carb. First thing I would check is that it is not getting stuck in high idle or something. That would be the most simple thing I can think of. Good luck with it and I am sure others will offer better suggestions.
sounds like the pressure vac test is in order you know how to do that right?
wigglesworth
Booned
Check your tank vent first, then fuel lines, impulse line, carb boot, and clean the carb out. AND THEN, if that doesnt fix it, do a pressure/vac test. Lots of info on site here.
timberwolf
Addicted to ArboristSite
Could it be lean on the LS. Sometimes too just unscrewing the jets and flushing it with a little fuel or crank it over with jets out and choke on can clear up the problem if it is just a little dirt in the carb.
redfire312
ArboristSite Lurker
My money is on an air leak. I'm working on a 460 that didn't have a p/c on it, so I put on a bailey's big bore kit and it ran pretty good but it just didn't act quite right. Come to find out I've got a major air leak on the clutch side crank seal, which the dealer says is pretty rare. I assume this is what caused the demise of the missing factory p/c.
Mastermind
Work Saw Specialist
I wouldn't want to run it much until I was sure it doesn't have a vacuum leak. Here's a quick and dirty test for it though...with it idling, spray some starting fluid in toward the seals, if it speeds up you have a leak. 
I'm going to swap the carb off the 440 and try that. If it doesn't fix it, then I will have a pressure/vac test. I don't see how it ran fine and then the next time I start it this happens. It wasn't even rode around in a truck or anything, just from the garage to the woodpile and back.
I took the tank vent apart and it hissed the first time and was stopped up, but it didn't fix it. I checked the carb boot last night and that didn't really have any effect on it. I might pull the limiter off the low also. The fuel lines are flexible and don't look bad at all. I'm hoping its in the carb.
I took the tank vent apart and it hissed the first time and was stopped up, but it didn't fix it. I checked the carb boot last night and that didn't really have any effect on it. I might pull the limiter off the low also. The fuel lines are flexible and don't look bad at all. I'm hoping its in the carb.
wigglesworth
Booned
Good deal, im glad you got it sorted out. I do find it funny that anytime somebody from the board see's a "Lean Condition" that it is ALWAYS an air leak to them, when there is a million other reasons that it could be going lean. Maybe folks just expect the worst. :dunno:
I do find it funny that anytime somebody from the board see's a "Lean Condition" that it is ALWAYS an air leak to them, when there is a million other reasons that it could be going lean. Maybe folks just expect the worst. :dunno:
that right there is the beauty of having saws that parts can be switched on saves a lot of time and aggravation.
Alright the search turned up nothing. Is there any reason a 440 carb won't work on a 460? The dolmar dealer has 3 zamas off of 044 and 440s but no 460 carbs. He is going to check with his cousin at the stihl dealer and see if he has a used one. I rebuilt and cleaned this one good and it doesn't do it as bad but still stays revved. I can flood it out if I adjust the high richer so it doesn't seem starved for fuel.
Just a thought, maybe this could help.
Have you checked if the carb diaphragm is fitted facing the wrong side up, or down.
I bought a s/h 024 that i thought had a crank seal air leak. When revved, it took ages to settle back down and was very erratic.
Turned out someone had reassembled the carb diaphragm the wrong way.
I just turned it over to face the correct way, and the saw runs much better now.
Have you checked if the carb diaphragm is fitted facing the wrong side up, or down.
I bought a s/h 024 that i thought had a crank seal air leak. When revved, it took ages to settle back down and was very erratic.
Turned out someone had reassembled the carb diaphragm the wrong way.
I just turned it over to face the correct way, and the saw runs much better now.
The metal weight, call it a wheel,washer or whatever you like goes toward the carb body and contacts the metering lever, some even hook into a slot in the metering lever others do not but they don`t work very well if in reversed direction.
Pioneerguy600
I sprayed carb cleaner in every little hole I could find on it. I wish I had an ultrasonic cleaner to put it in to see if there is something that didn't come out with the cleaner. I don't have air here at home to use.
