motor won't turn over with plugs in 1999 90hp force

johncrawford39

Recruit
Joined
Oct 6, 2012
Messages
1
Hi all, 1999 90 HP Force
My boat sat in the water for 3 weeks, batter went dead, boat went down. After pulling it out, it almost started but I had water in the fuel, I spent 4 hours draining the tank changing the filters. When I went back to start it the starter motor would engage but not turn the motor, pulled the starter cleaned it, found water and rust, still no good. I replaced the started still no good. I pull the plugs and it spins fine, if I put my finger over one of the plugs it stops turning when that cylinder starts to suck on my finger. (intake stroke I think) Is there a compression release that might be clogged?, or is it possible water got into the bottom of the motor and is causing compression internally? I wasn't home so I didn't see the boat in the water but was told the motor was under.
Thanks
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: motor won't turn over with plugs in 1999 90hp force

Hi, John.

Welcome to iboats. :)

First check your battery for full charge and output under load. If that is okay the problem is possibly in the battery cable connections, too much resistance to supply full current to the starter motor. Take them off, scrub the connections shiny and reconnect.
 

dutch420

Petty Officer 3rd Class
Joined
Sep 16, 2012
Messages
84
Re: motor won't turn over with plugs in 1999 90hp force

Hi john.

I had the same prob with my chrysler 85hp. Starter worked fine with no plugs put em in and it would not turn over.. I relpaced the starter and it works just fine .. Took the old one apart cleaned a bunch of times and was still a no go.. I know its not much help but my prob was starter it self. Rplaced it turns over lke new do u have a spare to try with?
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
Re: motor won't turn over with plugs in 1999 90hp force

If there is any doubt the engine went under water, you need to inspect at least the intake manifold and the reed assembly and check the crankcase to make sure it is not filled with liquid. Any amount of liquid in the crankcase can cause a backpressure on the pistons that can lock the piston. Otherwise, it could just be the connections especially the negative cable on the block.
 

TwoFish

Petty Officer 1st Class
Joined
Aug 7, 2010
Messages
373
Re: motor won't turn over with plugs in 1999 90hp force

I am in the process of changing motors. I had a 1998 75hp. Whilst removing the old motor I discovered a crack in the battery cables right where they enter the cowl at the front of the motor. I had been having trouble with the starter working slowly for a while. The flexing from tilting the motor must have fatigued the cables over time. It wasn't visible until I removed the cable.
 
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