Mercruiser 888 Starting Problem

[vaboatdoc]

Mercruiser 888 (302 Ford) has a starting problem. Engine cranks and seems to fire up and acts like it wants to run but as soon as it starts it shuts off. Havent had alot of time to mess with it but seems like its getting enough fuel and point gap is all good and has a new set of points and a condenser. Is it a ignition timing problem or am i barking up the wrong tree. Any advice would be great help!!

 

[Bondo]

Re: Mercruiser 888 Starting Problem

Ayuh,....

It sounds like you're lacking Power with the key in the Run position,....

In the Start position,...
The Igntion draws it's power from the Starter.....

 

[Maclin]

Re: Mercruiser 888 Starting Problem

If it dies right when you let the key come back from starting position then that sounds like the classic problem of a bad ballast resistor or wiring problem in the ballast circuit to the coil. The coil has power during cranking because the ballast circuit is bypassed, then when the key is moved back to run from start the coil loses power and the engine dies. Most engines work this way, not real sure about the Merc 888 but that is where I would start looking.

 

[BrockR]

Re: Mercruiser 888 Starting Problem

i had this same issue a few weeks ago my key switch was bad and not making good contact on the run side of the switch going to the coil.

 

[WizeOne]

Re: Mercruiser 888 Starting Problem

A simple and easy test. Get a jumper wire and connect it from the battery + to the coil + and start the engine. Does it run? If so then the run circuit from the ignition is bad. (Usually the ballast resistor or the resitor wire.)

FWIIW, if I am reading the wiring diagram correctly, it appears that the 888 (& 898) use the choke coil as the ignition coil's ballast resistor.