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Rod McInnis
 
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Default Rebuilding an Inboard


"Douglas St. Clair" wrote in message
...


I have a 1970 427 Crusader. What determines when an engine should be
rebuilt?


Signs that an engine needs rebuilding:

Low oil pressure
Rod knocks
excessive valve noise
low compression
excessive smoke
excessive oil consumption
oil leaks



What's involved in rebuilding an inboard?


Get the engine out of the boat. Then it is just any engine.

You will have additional issues about the exhaust manifolds. If the engine
needs rebuilding there is a good chance that the manifolds are about to rust
out as well.

The starter, alternator, distributer and all parts of the fuel system should
be "marine". Don't substitute automotive equivalants.


How much would it cost
to have it professionally rebuilt?


Sorry, can't answer that.


I found this link...
http://www.kanter.com/p30-fon.html#fo12

Does this "engine overhaul kit" contain everything for a rebuild?


Well, I don't see "freeze plugs" on the list, and I would certainly
recommend replacing them on a marine engine, especially one that was raw
water cooled. There are couple that are a real bitch to get to once the
engine is all assembled and in the boat, and if they rust out in a year or
two you will be really sad that you didn't replace them when it was easy.

There will be those who argue that the cylinder head gasket should be
"marine" rated, which supposedly makes it more resistant to the continuous
flow of raw water. I know lots of people who have used standard automotive
gaskets without any problem so this is your call.

I would not use a camshaft that was advertised as "high performance" in a
boat. You want low end torque, not top end. I certainly wouldn't trade a
steady idle for a little more RPMs.

Note that you can't order this kit until you have disassembled your motor
and completed any boring or grinding that needs to be done. If you need to
bore out the cylinders you will need to know how far it has been bored out
so you can specify the correct sized pistons. Same with the crankshaft and
camshaft, if they need to be ground to get the bearing surfaces round again
then you will need oversize bearings that match.

If I was spending that much time and effort on the engine I would certainly
replace the valves and guides ("deluxe kit").

The disassembly and reassembly of the motor is easy. You will need to find
a machine shop that can check/grind the crankshaft, replace the valve guides
and grind the valve seats, and clean up and possibly bore out the crankcase.
It sure helps a lot if you have an engine stand to hold the engine while you
work on it. You will need some sort of crane of A frame over the boat to
get the engine out and back in.

You might want to consider rebuilding the carburetor while you are at it.

Rod