motor will not turn over 1988 200 horsepower

deerejunkie

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Joined
Aug 1, 2015
Messages
6
motor

i have a 1988 mercruiser with a 200 hp engine I think it is a 305 chev it will not turn over the battery is hot and has full charge when I bump the starter the engine tries to turn I have had the boat running a few weeks ago for first time this was surprised it fired right up put in lake and ran good for about 30 min. the motor shut down upon decelerating the engine after a while finally got it started but it acted like was trying to lock up . figured we had fuel problem since the boat was bought last year and run very little and we did not know how long it had been since fuel system had been maintinced drained and clean tank replace water separator filter (filter had lot of water in it) cranked engine for vary short time and ran ok.. went to go to lake to test it out and found the motor would not turn over
 

deerejunkie

Cadet
Joined
Aug 1, 2015
Messages
6
i have a 1988 mercruiser with a 200 hp engine I think it is a 305 chev it will not turn over the battery is hot and has full charge when I bump the starter the engine tries to turn I have had the boat running a few weeks ago for first time this was surprised it fired right up put in lake and ran good for about 30 min. the motor shut down upon decelerating the engine after a while finally got it started but it acted like was trying to lock up . figured we had fuel problem since the boat was bought last year and run very little and we did not know how long it had been since fuel system had been maintinced drained and clean tank replace water separator filter (filter had lot of water in it) cranked engine for vary short time and ran ok.. went to go to lake to test it out and found the motor would not turn over but you can it is trying to turn over tried to get spark plugs out but they seem tight so do not to put extra pressure on them so I to turn over motor with breaker bar on crank bolt no luck. wondering if I have out drive issue locking up motor . where should I go from here
 

nickmo

Petty Officer 2nd Class
Joined
Apr 2, 2010
Messages
117
Pull the spark plugs and try turning it over. See if water comes out of the cylinders. Sounds like water got in the motor. Hope not.
 

Bondo

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Apr 17, 2002
Messages
70,465
tried to get spark plugs out but they seem tight so do not to put extra pressure on them

Ayuh,.... Welcome Aboard,.... Is this a saltwater boat,..??

The spark plugs Gotta come out,... that's step #1,...
 

deerejunkie

Cadet
Joined
Aug 1, 2015
Messages
6
got the plugs without breaking any off all cylinders are dry and the oil looks good as new no milk etc in it have breakover on crank bolt and will not turn over hooked good hot battery to it and bumped it engine pulley moves when starter engaged so I do not feel starter drive has motor locked up. where do I go from hear I want to learn about these setups since I got a basket case to restore after I get this problem solved want to take this boat on vacation in about two weeks . THANKS FOR HELP
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,092
FIRST, DO NOT USE THE CRANK BOLT TO TURN A MOTOR OVER

With all the plugs removed did you notice and wetness on the plugs?
Did any water exit the plug holes?
Did you check the oil level in the drive before use?
Did you check the oil in the drive after lockup?
Remove the drive to isolate the trouble.
 

deerejunkie

Cadet
Joined
Aug 1, 2015
Messages
6
one plug had a very very little dampness appear to fuel since it evaporated fast. I did not check oil level in oil before or after , I will go to my tech manual to read up on drive removal thanks for advice I will take breaker bar out of boat now
 

deerejunkie

Cadet
Joined
Aug 1, 2015
Messages
6
pulled drive found upper gear case with virtally no lube bearings froze up . think I got a better handle on problem and motor is free THANKS THANKS I have restored old tractors in the past they will leave on the roadside but not a drift in a big lake
 
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