1984 Mercruiser GM 350 engine no start, not even trying to fire

Seems to be some uncertainty about engine rotation here; compression test does not reveal right or wrong. Only reliable way is to take one valve cover off, rotate the engine slowly by hand and observe the sequence the two valves in a cylinder open and close.

baeckmo said:

Seems to be some uncertainty about engine rotation here; compression test does not reveal right or wrong. Only reliable way is to take one valve cover off, rotate the engine slowly by hand and observe the sequence the two valves in a cylinder open and close.

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It is GM 350 engine, oil pump can not spin CCW, that is definitive, it is not compatible with life for an engine to have no oil pressure.

sdowney717 said:

It is GM 350 engine, oil pump can not spin CCW, that is definitive, it is not compatible with life for an engine to have no oil pressure.

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Fair enough, but do you know if the camshaft is chain- or gear-driven?

baeckmo said:

Fair enough, but do you know if the camshaft is chain- or gear-driven?

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That was my reasoning for checking the cam/crank connection.

baeckmo said:

Fair enough, but do you know if the camshaft is chain- or gear-driven?

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That makes no difference right now.
It has a CCW starter on there and it is spinning the wrong way.
If I am standing behind the motor looking at the belts, the engine pulleys turn to the right, and distributer spins to the left. Distributor must spin to the RH, CW direction, that can only mean it needs a CW starter.
A lot of verification symptoms, like plugs stay dry, no gas gets into cylinders, gas spits out the carb, rotor turns wrong way, engine wont fire.
These gear ratio velvet drives 1.91 to 1 spin the output shaft reversed from engine input.
Guy says they gave him a CCW starter.

So then by logical deduction, it must need a CW starter instead of a CCW starter.

The engine is also a top mount rear entry starter position which also reverses the starter direction compared to a front entry low mount starter.

Yes, that is the logical deduction.

Handy reference chart
His engines have starter mount , lower right picture


ARCO Marine Catalog (marineengine.com)

I was convinced on Friday the starter was the wrong one. You ought to be able to also verify the starter rotation by the numbers on it.

"....Engine is portside, so should be standard rotation....". Sorry, missed that info when quick-reading the thread (due to my too fast reading and/or too slow english....). Seems the starter explains it all. But with the previous owner history (not beeing overly mechanically minded?), as a safety measure I would check that the transmission oil pump is set up for the correct input rotation as well.

It runs!
Put new correct rotation starter on,
First start test video

https://photos.app.goo.gl/UWZQuGygHKDeJtU98

sdowney717 said:

It runs!
Put new correct rotation starter on,
First start test video

https://photos.app.goo.gl/UWZQuGygHKDeJtU98

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Most excellent