I have a 85 ty350 that has a surging rpm problem. After it is warmed up it will take what seems like forever to come down off higher rpms to a near idle and then it will surge up and down somewhere between 600-1200 rpm.

Did these 350's have a heavy flywheel back then that causes them to be so slow coming back down to idle? I have checked for air leaks on the intake and the carb has been cleaned as well as a new air filter. Could the crank seals cause this? It really seems to "hunt" to find a idle speed that is consistant.

Thanks!

Sounds very much like crank seals to me.

Graham

The TY350 has a flywheel just slightly lighter than does a Ford 9N tractor, so it does take awhile to wind down.

Sounds like crank seals, though.

Wait for Stoodley (JSE) to chime in.

I figure if there's anything he doesn't know about a TY350, it doesn't need to be known,

Edited June 13, 201115 yr by charliechitlins

The TY350 has a flywheel just slightly lighter than does a Ford 9N tractor, so it does take awhile to wind down.

Sounds like crank seals, though.

Wait for Stoodley (JSE) to chime in.

I figure if there's anything he doesn't know about a TY350, it doesn't need to be known,

I agree he seems to be very knowlegable on almost all topics. Thanks for the comparison on the the weight of the flywheel! Sometimes I wish it had a toggle kill switch rather than a momentary one. I have already ordered seals as it can't hurt.

I agree he seems to be very knowlegable on almost all topics.

I'm pretty sure Jon has had his '86 TY350 since new!

Sounds like you could have an air leak somewhere and or the mains are bad. Yes, it has too heavy of flywheel. To make it sweet shave 12-14 oz off the outside of the weight. If you`d like to challenge your clutch you could remove the weight completely.