Onan 20hp Junk!

[Wheelbearing 49]

 

Sucks

[Wheelbearing 49]

front intake valve sets out and rear is rocking

[Forest Road 594]

Oh no!!!! Didn't you so a full rebuild on that motor?

[Wheelbearing 49]

Snow blowing did this.                               The rear seat was already done.   These things just loose there seats

[MalMac 1,328]

Can you save it or is it too far gone. Maybe I should ask if you want to try and save it? That's why I have a Kohler on stand by for when mine let's go. Just not a fan of the Onan. When their going good there great but just too many problems for my taste. But I guess you could say that about any motor they all have problems but the Onan sure got it's share.

[546cowboy 301]

Never seen a front seat out before. Huh!

[stevebo-(Moderator) 8,059]

Oh boy... at least you are a guy who can fix it. Maybe you should not have run it *** for 24 hours on snow duty detail for the town. Maybe they will pay to repair the motor   Just kidding. Hope you get her going soon. In the mean time if you need a donor motor I have one here you are welcome to use for a few months until you get yours repaired. Let me know.

[Wheel-N-It 2,967]

Hopefully you can find an affordable Onan. If not, its probably time for an alternate repower.

[ericj 1,576]

i just had an onan to the machine shop and got both intake and exhaust seats done on the back cylinder. last night i finally got around to adjusting the valves, while doing this i noticed that the front cylinder looked good around the valves but the back was all black from being burnt. that sucker got hot. the cam side of the block looked okay it was the valve side that was black. so a hot block dissimilar metal and differant cool down and i guess thats why the valve seats pop.do you notice any thing such as this on your motor?

 

eric j  

[woodchuckfarmer 333]

I had both intake seats replaced on mine , cost was 130 bucks....good luck with yours.

[mattd860 161]

Yikes. I better check mine. I spent about 10-15 hours blowing the 30" of snow off my very long driveway and 6 of my neighbors driveways!!! I did notice sort of a rattling/knocking sound on occasion but the tractor never lost power or felt weaker.

 

One thing I noticed was that the screen in front of the flywheel fan often clogged up with ice but I tried to clear it often. Maybe yours also clogged preventing air from cooling the heads?

[richmondred01 2,209]

Not junk. It can be fixed. I've done several.

[SAM58 30]

Well, when the Onan gives up the ghost,   you can always repower with this...

 

http://www.smallenginewarehouse.com/search.html?cat=Repower+Wheel+Horse+520H&parent=Categories+%3A+Engines+%3A+Repower+Engines

 

This looks like a really good option, wired and ready to set into your 520H.

[CRE1992 135]

Im sorry to see that happened after all the time you put into it. Looks like a good candidate for a repower.... Fuel Injected Kohler command ????? Also if you decide to not go with the onan again... Let me know whatcha want to do with the custom exhaust..

[stevebo-(Moderator) 8,059]

If I know Bob (wheelbearing) I would say he has it just about fixed by now. He is an animal when it comes to getting things done.

 

Bob..... don't make a liar out of me... lol

[richmondred01 2,209]

I rebuild them for 250. Seems like a bunch of money to repower for 1600 bucks.

[SousaKerry 500]

Well, when the Onan gives up the ghost,   you can always repower with this...

 

http://www.smallengi...Repower Engines

 

This looks like a really good option, wired and ready to set into your 520H

 

I think I'd slide a one lunger Kohler in there before I ever put a Briggs and Scrap-iron in especially for $1600 bucks....  ouch!!

[oneroadkingman 53]

Wow I think 1600 dollars is a bit steep for my pocketbook I think I would rebuilt what I had first it worked for all these years without a problem jus saying

[stevebo-(Moderator) 8,059]

If I were to spend big money repowering it with a new motor I would lean towards a honda 20 or 24hp.

[fireman 1,021]

Put a diesel in it! Gasoline nowadays sucks.

[Ken B 3,116]

Put a diesel in it! Gasoline nowadays sucks.

I agree Jeff. If the Onan on my 520 takes a dump that is what I'll most likely do.

[Tankman 3,515]

 

Put a diesel in it! Gasoline nowadays sucks.

I agree Jeff. If the Onan on my 520 takes a dump that is what I'll most likely do.I third that motion! Must admit however, my 520-8 Onan hour meter reads 2500± hours and runs great.

Not knowing the Horses history, there is a clue leading me to believe the engine might have been replaced.

I shudder seeing replacement costs, I'll go with a Kohler one cylinder or a diesel repower. I have four Kohlers, 2 x 12hp, 1 x 14hp and 1 x 16hp, all older than the Onan, all runnin' great.

Love diesels, had many. A diesel project would give me something "new" to play with. :smile:

[fireman 1,021]

I hadn't started my diesel since the fall. Rolled it outside last week and before I even could get my fingers off the key it fired right up and purred like a kitten! Not to mention it sips fuel at such a slow rate it's amazing.  

[mattd860 161]

What would be a compatible diesel motor for the 520?

[Wheel-N-It 2,967]

Diesel !!! Thats what I was thinking when I said "alternate" .   You know like the V-Twin diesel Kelly is putting in his C-195. Thats my idea of a nearly perfect repower project for a 520. I have a 520 roller sitting in the barn waiting for me to get the time and money to do this transplant.