Onan LP generator question

Question

We’re looking to buy our first motorhome. I found a coach that looks just about perfect for us, except it has an Onan LP generator that hasn’t been run in about 4 years. I’ve agreed in principle to buy the coach, provided everything else checks out okay and the generator issue isn’t a huge problem to remedy. It is over 700 miles away, so I will soon see it for the first time.

The seller says the generator fires, but does not continue to run. The seller is agreeable to a price adjustment if fixing the generator turns out to be a big expense.

What damage is likely done to the LP generator after sitting for 4 years? What in particular should I be looking for when I inspect the coach?

Thanks for your input!

Wayne

sdetweil · Answer

there should be a fault code flashed on the generator start panel.

https://www.equinerv.com/node/2127

I bought a used Onan 7kw generator last summer which did the same thing, start, then stall.
the fault code 3, error code 15 said generator under voltage.

this forum on smokstak.com is dedicated to onan generators.

mine turned out to be the pulley coupler under the engine that drives the belt to the generator armature. the coupler is rubber between the two metal sections, and the rubber degenerates over time. $40 including a new belt and a couple hours of my time. (gotta take the bottom of the unit off, and the engine flywheel to replace the coupler)

wayne_dohnal · Answer

If the generator is a Microquiet manufactured approximately in 2008 there's a chance it has defective valve springs that fracture in under 100 hours of run time.  It's fairly easy to pull the valve cover and inspect them.  If broken, the best case is replace the springs and all is ok.  The worst case is replace the generator.  I was lucky enough to have the best case scenario.

generator_jim · Answer

You could have dirty slip rings and/or stuck brushes.  The unit needs generator voltage to remain running.  No voltage, no oil pressure = shutdown.JimL

empty_nest__soo · Answer

Thanks for the replies.The generator is a vintage 1995 -- 1996 Onan 6300 watt LP model.  It's on a 1996 model coach.  I should have mentioned that in my initial post.Thanks for the info on the fault codes.  I will pass this on to the seller and maybe he can sort things out to my satisfaction.Wayne

texas · Answer

This is why we need to know full model and serial number. Units back then didn't have fault Codes.

Forum Discussion

Onan LP generator question

5 Replies

About Technical Issues

Related Content

Onan Generator

Question about Onan Generator

Generator question

Generator operation

Cummins Onan Generator