mvvs-58 idle down issue
 

hi guys i have a mvvs-58 that has been a great engine but just the other day it does not want to return to idle
i have checked all the normal issues that can cause this issue servo - choke - fuel lines - tank - radio
the motor runs great at anything above idle but when i lower the throttle it stays at a high idle
any one have this type of issue with there gassers

RE: mvvs-58 idle down issue
 

Hi!
The only thing that could hinder the engine to slow down is something that restrict the air coming into the carb.

RE: mvvs-58 idle down issue
 

Possibly a vacuum / air leak,crank seal ,loose fitting pulse line maybe,or slight restriction in carb idle circuit leaning mixture if idle mix set slightly rich prior are some things to check.

RE: mvvs-58 idle down issue
 

I would have to agree on the air leak. There is the remotest possibility that the low end is too lean. I had an engine that wouldn't idle down to its low idle in the air and that turned out to be the problem. Totally different engine though.

RE: mvvs-58 idle down issue
 

thanks guys i think it is an air leak also i have checked the carb and it is tight so i guess it is time to pull the engine and do some searching

RE: mvvs-58 idle down issue
 

Sounds like a leak to me... could be a loose muffler as well.