Onan 12.5hp boxer flat head not moving

#1
My onan will move back and forth a few degrees but it doesnt go all the way. its definetly rusty and crusty inside but the pistons move so does the exhaust valve.:grind:
 

65ShelbyClone

Well-Known Member
#5
If the cylinders are rusty or if there is any rust at all visible through a spark plug hole, then the heads need to come off. [/story]

And if the cylinders are pitted from corrosion, then it won't last long even if you do get it to run in that condition. I have an '86 Kawasaki GPZ600 on my to-do list right now that has a cylinder so rusty that it was stuck and sounded so gritty when it came loose that it was audible through the cases. I got it fired-up anyway, but that cylinder was deteriorating rapidly in the few minutes I had it running. New pistons & cylinders are already on-hand.
 
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#6
Parts for that are extremely expensive.
I mean Cummins will demand a pound of flesh from you just for the privilege of buying OEM replacement parts.

Strip it and find out exactly what you are into before you do something you regret

In the event you scrap it can you send me a PM.
I might be willing to buy some of the bits left over ( shipping to Canada is expensive and I am not willing to spend a lot for rusty crusty and used)
 
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#7
It would move perfectly for about 5 degrees than stop. If I take the heads of I will lunch the head gaskets in the process. Right now I literally have 4 hours or 7 a week of free time and I just sit and chill. In about 4 or 5 weeks I'll work on it. So that's were I'm at.
 
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