Starter wont stay engaged long enough for engine to start

[mattu]

I have a 1989 150 that runs well, and starts immediately when warm. But when cold, as soon as any cylinder fires, the starter disengages. I am certain that if the starter would remain engaged for a few seconds, the motor would start right up. Because of this, it takes me about 30-50 tries to have it finally start, and the people at the boat ramp are giving me very nasty looks!

I have replaced the starter, and the problem remains. Even the slightest fire on one cylinder and the darn thing pops right out.

Any help or suggestions?

 

[Chris1956]

Re: Starter wont stay engaged long enough for engine to start

That is the way the starter is designed to work. Your engine is the issue. Does the choke system work? Is the motor tuned properly?

 

[mattu]

Re: Starter wont stay engaged long enough for engine to start

the choke system works, when motor goes to stall if you press in key (Choke) motor keeps running. starter works fine if engine is warm.

 

[175se]

Re: Starter wont stay engaged long enough for engine to start

are you bumping the primer to keep it running on start? are you making your squeeze ball is pumped up?

 

[boobie]

Re: Starter wont stay engaged long enough for engine to start

Check your spark when the problem occurs. It should jump a 7/16" open air gap on a spark tester.

 

[mattu]

Re: Starter wont stay engaged long enough for engine to start

yes, bumping primer and ball is pumped up. also start in neutral with throttle cracked ? to ? way. where do i purchase a spark tester and how does it work? this problem only occurs on cold engine, starts right up when warm!

 

[Bosunsmate]

Re: Starter wont stay engaged long enough for engine to start

Most car part shops have them.
Do you hold choke in while turning key or just bump it to keep it going?

 

[mattu]

Re: Starter wont stay engaged long enough for engine to start

bump it 3 times before turning over, then hold in til starts then bump it to keep running if needed. do you turn motor over when using spark checker or have it running?

 

[Joe Reeves]

Re: Starter wont stay engaged long enough for engine to start

I have a 1989 150 that runs well, and starts immediately when warm. But when cold, as soon as any cylinder fires, the starter disengages.

Check the compression of your engine.

That condition exists on many engines when the compression on a particular cylinder is normal BUT the following (or preceeding) cylinder is low on compression for some reason. This tricks the electric starter into thinking (so to speak) that the engine has started and the bendix disengages.

This condition is so common that on the 1987 V6 Loop Charged engines (to pick one), the compression must be taken with all of the spark plugs installed excepting the cylinder that is being tested, otherwise the bendix disengages resulting in faulty compression readings.

 

[mattu]

Re: Starter wont stay engaged long enough for engine to start

how many psi variance between cylinders would cause this problem (roughly)? thanks for the help! should i take a compression reading when engine is cold or hot? would it make a difference if engine is still fogged? (winter storage)

 

[Bosunsmate]

Re: Starter wont stay engaged long enough for engine to start

bump it 3 times before turning over, then hold in til starts then bump it to keep running if needed. do you turn motor over when using spark checker or have it running?

I dont think you should bump it three times before turning over and also holding it in til it starts as that could be flooding it.
Try starting it without bumping it beforehand. And ease up on the choke if it doesnt start, alternate choke on and off so you dont flood it.
I check spark with motor not running, but i suppose you could do it while its running

 

[Bosunsmate]

Re: Starter wont stay engaged long enough for engine to start

how many psi variance between cylinders would cause this problem (roughly)? thanks for the help! should i take a compression reading when engine is cold or hot? would it make a difference if engine is still fogged? (winter storage)

15%
hots better but dont stress on that,
fogged will probably increase the numbers a bit and will might contaminate your tester with quite a bit of oil