To buy or not to buy...

[webb]

I am looking at a 1979 85hp mercury outboard with the following compressions: 125 95 125 125 125. Should I walk away from this engine because of the 95 compression? The engine is represented as having good spark and operational but it is not in a boat for testing.

 

[Laddies]

Re: To buy or not to buy...

All 850 built after the early 60s are 4 cyl. What ever it is it's beyond the 10% differance between cyls. that recommended. If the engine has been sitting around it could be stuck rings that might lossen up but not knpwing it could also be a bad cyl wall and the engine would be junk. Your money, your spin of the wheel!

 

[Scaaty]

Re: To buy or not to buy...

I'd pass on a low cyl too...it being 70's, could be a leaking/cracked exhaust/water jacket, which is letting water into the cyl (takes little water), and rusting a ring, hence, 95psi..it will get worse as it does in the wall.
And as they have no removeable head (I'm pretty sure yours is), the crank and all must be pulled for a hone/bore

 

[Tadd_P]

Re: To buy or not to buy...

agreed leave that motor in the hands of whomever has it. He probably wouldnt be selling it if it were in good working order!

 

[webb]

Re: To buy or not to buy...

Thank you Gentlemen for your collective wisdom...time to look for another engine.