Merc 140 cam?,,, I'm dumbfounded!!!!

[RandyJ]

I've done this before with no problem... I swapped my old tractor for my cousin's old boat which has a mercruiser 140. He had put a new cam gear on it but it wobbled loose. I happened to have an old 140 on the ground so just pulled out the cam and swapped them out. When I tried to start the boat NOTHING! The best I could do was to get it to backfire a little. I even pulled the motor back out and checked the gear alignment and rotor position... though I do question the firing order (okay, what's the firing order?)... any other thing I might check to get this baby cranked? It was running fine with the old cam in it but no good with a loose and wobbling cam gear rattling on the engine.

 

[Don S]

Re: Merc 140 cam?,,, I'm dumbfounded!!!!

It was running fine with the old cam in it but no good with a loose and wobbling cam gear rattling on the engine.

Gee, what a surpise.

Ya suppose that if the cam gear is loose and wobbling, that there might be something wrong.
Maybe wrong parts ????????

 

[RandyJ]

Re: Merc 140 cam?,,, I'm dumbfounded!!!!

Yep Don, something was wrong but it ran with the cam that had a loose and wobbling cam gear... now it won't start at all....??????

 

[mariner1900]

Re: Merc 140 cam?,,, I'm dumbfounded!!!!

Did you make sure that the engine was on #1 TDC on the firing stroke before fitting the distributor?

This requires the engine to be turned 360 after aligning the cam timing gear marks as the cam timing marks on the gear are #4 TDC.