Onan Quiet Diesel Crank Pully Issue

[Ericbsc]

I have a 10 kw onan quiet diesel. Last week on a trip to MS it keep cutting off. This was odd considering I loaded it with 3 roof airs, windows open 90 deg. for 8 hrs when I bought it used. It would run one air. When the second was turned on it would shut down in a few minutes. The high coolant temp error would flash. Foud out that the crank pully has a keyed hub and a molded in rubber isolator between it and the pully. The rubber gave out and it was slipping between the two. I've never seen one with an isolator much less one that went out with 800 hrs. Anybody else had this problem? This unit has an Isuzu power plant.

[bevans6]

That is usually a harmonic balancer to control vibration in the crankshaft.  Not speaking specifically about your failure, we have had real problems  getting good harmonic balancers lately, for some of the engines I work on.  A lot of failures on new parts, people are going back and digging the old stuff out of the bins and putting them back on.  I would just replace it  with a new one and check it from time to time.  You can mark it and see if it moves, or poke at it with a stick and see if it is loose, or see if the rubber is deteriorating.

Brian

[Ericbsc]

Thanks, I have one coming today. I have never heard of one coming completely apart. I will watch it!!

[Ncbob]

If you don't believe me ...ask Nick. Buy your parts from your Onan/Cummins distributor. Belts for sure. Nick found out the hard way...and the harmonic balancer is to coer up some of the imbalances in a cheaply built engine. I was an Onan Dealer for over 20 years and trust me, while they built quality products , and when Cummins took over it was just an outlet for Cummins engines and now they'd like to see it disappear... and they're working hard to that end.

A couple of years ago I was at Cummins in Chatanooga and they had pallets full of 8 KW's they'd replaced under warrant...all RV units. I wouldn't touch an Onan Generator with a 10 foot pole.

NCbob

PS. I have a 12.5 Kohler.