84 omc 3.0

Hello everyone!
I have a 1984 sea swirl open bow with an OMC 4 cylinder 3.0 litre Model number: 302STHCRA Serial number: J 793614 that I am trying to restart after seating for two years.
I need to know what kind of motor this is? It looks like a ford or GM? I also would like to know if anybody has the firing order for this baby including a picture if possible of the distributor rotor position. I've try different order and it seems like no luck is on my side. the engine won't start its getting spark and gas but has two mid cylinders with low compression (46, 56 lb/sq in ) . Will any body please help. Thanks.

GM 4 cylinder similiar to the mercruiser 3.0 1,3,4,2 #1 in front, #4 in rear

G84swirld said:

two mid cylinders with low compression (46, 56 lb/sq in ) .

Click to expand...

sounds lt blew the head gasket between 2 and 3...

did you hit it with starting fluid? that's a good way to blow it, or may have had water in the cylinders.

I'd do a quick check to make sure the valves on those cylinders are pumping up and down like they should, and if so... then off with her head.

Thanks for the info Bt Doctor.

Hystat; No I Have not Tried starting fluid ....I cleaned the carb and checked the coil, condenser, points, wires and plugs for functionality they seemed good. Will it start with those two cylinder low on compression?