mercruser 470

[hustonr123]

I just bought a 84 19ft boat and it has the 470 in it. When I bought it the person said it had a stuck valve so I ripped the head off and had it remaned. Tonight I reassembled it and still spits gas out of the carb and wont start. So then i fugured that it was the timming so took off timming cover and checked it. It looks to be perfect by what the book says. If anybody can help Id appreciate it.

 

[Don S]

Re: mercruser 470

So then i fugured that it was the timming so took off timming cover and checked it.

The ignition timing, not the Valve timing.
You check the ignition timing using a timing light and turning the engine.
Valve timing you pull the timing cover and see if the marks line up on the gears.

 

[hustonr123]

Re: mercruser 470

wont start to check with a timming light. I did take the timming cover off and looking at the marks on the gears it is real close.

 

[Don S]

Re: mercruser 470

Crossed spark plug wires will cause what you are experiencing, along with the distributor turned too far or way out of time. Even moisture or a cracked distributor cap can cause it.
Start by getting the engine to #1 TDC, then check the rotor and see if it's pointing to #1 spark plug wire on the distributor cap. Then check the firing order and direction of rotation.
You have points, is the dwell set?
Is the coil tower arching to either of the small terminals on the coil?

 

[hustonr123]

Re: mercruser 470

checked all of that two times. acts like the pistons on the way up on compression and the intake valve is still open

 

[hustonr123]

Re: mercruser 470

Still stump on this. does anybody have a good pic of what thiming marks on the timming chain are and tell me if the timming chain is somthing that goes bad in a 470

 

[Bt Doctur]

Re: mercruser 470

When you installed the head how did you set the pushrods.
that motor is hyd. 3/4 down from "0" lash. Intake too tight?