Starting problems

[Father's Day]

Hello brothers
I have a Merc 150 EFI starts right up and runs great. I can get out to my spot turn the boat off and make a couple of short drifts 10 min each no problem. Then if I do a long drift about 20 /30 min wont start, wants to at 1st but will not start,than get a couple of beeps and wont turn over at all. wait about 30 min starts right up. Any ideas would be appreciated

 

[Hookup1]

Check fuel filter can. Make sure its tight (not sucking air) and dump out to check for water. Check filter on engine too.

 

[seasick]

When you say it won't turn over at all, clarify if it wont crank at all or cranks but doesn't fire up.
What is the exact motor model and how many beeps in what pattern do you hear?

 

[Fishtales]

I’d check fuel and battery in that order first.

 

[Father's Day]

Check fuel filter can. Make sure its tight (not sucking air) and dump out to check for water. Check filter on engine too.

Will do thanks

 

[Father's Day]

I’d check fuel and battery in that order first.

just bought new battery and going to check fuel thanks

 

[Father's Day]

When you say it won't turn over at all, clarify if it wont crank at all or cranks but doesn't fire up.
What is the exact motor model and how many beeps in what pattern do you hear?

2000 Merc 150 EFI cranks like it wants to turn over a few times, then it turns maybe 2-3 teeth on the fly wheel and stops and i get two beeps. If I keep trying same thing, if i wait 1/2 hour she starts right up. I can run her for hours with no problem at all, runs great.

 

[seasick]

I don't know what 2 beeps mean, sorry.
It seems to me that when you try to start, the motor cranks over and seems like it wants to fire up but it doesn't and eventually after a few tries, the flywheel only moves a bit and then the alarm sounds.
That could be a bad starter that is binding after heat soaking (absorbing heat from a hot motor). Whether the battery is weak and is the cause it not clear to me since if it were, why would it work after waiting?
My other thought was hydraulic lock caused by raw gas leaking into cylinders usually due to a bad carb.

One think that might support a bad battery ( or a dirty connection) is that the Merc ECUs can be picky about low voltage and motors will crank but no spark is commanded. If there is a bad electrical connection somewhere in the battery cabling and probably on the motor, that could expand as it gets hot and make an even worse connection.

Keep us updated and good luck