I'm to sell my boat which has a 90HP Johnson V4 on it....
One of the possible buyers took the spark plugs off and tested the
combustion of each of the cylinders... one of them failed badly....
Is it worth fixing these things???I don't want to fix it myself cause I
might not get the money back when I sell it.... when a motor of this age
(about 1985) and has these problems i igt worth fixing??


Thanks

"GC" wrote in message
...
I'm to sell my boat which has a 90HP Johnson V4 on it....
One of the possible buyers took the spark plugs off and tested the
combustion of each of the cylinders... one of them failed badly....
Is it worth fixing these things???I don't want to fix it myself cause I
might not get the money back when I sell it.... when a motor of this age
(about 1985) and has these problems i igt worth fixing??



You have to remove the cylinder head to see how bad the damage is. If the
cylinder is not deeply scored, it can be bored oversize and a new piston
fitted.

Being a 21 year old motor, it probably would not be economically feasible to
repair it, unless you planned on keeping it for a few more years. If it is a
salt water motor, then it is not worth fixing.

Bill Grannis
service manager

I had a look at my engine again today...
I found that the red wire that goes to the little box which goes to the
spark plug, had a bad connection...
So I wonder if this was part of the problem before.... the spark plug wasn't
firing and in turn the cyclinder wasn't firing (sorry for my non-technical
terms hehe)
Anyway I cleaned the grotty spark plug up, and fixed up the wiring
connection and then started the engine again and let it run for about 5
mins......
I then turned it off again and took out the spark plug..... its was looking
a bit better... looked like it had a bit of oil on it like the other spark
plugs..... The cyclinder may be working again now???
Without a compression tester, how can I safely check to see if the cyclinder
is firing??
Can I disconnect the cable going to each of the other spark plugs and just
leave the suspect one in??? What results can I expect from this??

So is it possible that the engine failed the compression test simply because
the spark plug hasn't been firing properly in the past??
Thanks




"GC" wrote in message
...
I'm to sell my boat which has a 90HP Johnson V4 on it....
One of the possible buyers took the spark plugs off and tested the
combustion of each of the cylinders... one of them failed badly....
Is it worth fixing these things???I don't want to fix it myself cause I
might not get the money back when I sell it.... when a motor of this age
(about 1985) and has these problems i igt worth fixing??


Thanks