1988 Mercruiser 3.7 electrical problems

mgilker

Cadet
Joined
May 4, 2011
Messages
17
im working on an '88 mercruiser 3.7 and it is having serious electrical issues. when a battery is hooked up, everything seems fine, but when the engine is cranked over it cranks slow or barely at all, even with a fully charged battery, and when its cranked the battery cables and the terminal begin to heat up quickly. it seems like it's a short somewhere but I can't find it and I have no other wires but bare essentials hooked up.. im think that it could be the built in generator/alternator because it's pretty much the only other thing hooked up... anybody have this problem before or know anymore???
 

dingdongs

Chief Petty Officer
Joined
May 29, 2009
Messages
649
Re: 1988 Mercruiser 3.7 electrical problems

Is it a good battery with good amps .Anew battery is a good start rather than one that is tired.Check all grounds are clean to engine first.Remove plugs and try too.if it is still having trouble could be a drive seizure so remove too.If that is not spinning now your batteries fubar.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,468
Re: 1988 Mercruiser 3.7 electrical problems

im working on an '88 mercruiser 3.7 and it is having serious electrical issues. when a battery is hooked up, everything seems fine, but when the engine is cranked over it cranks slow or barely at all, even with a fully charged battery, and when its cranked the battery cables and the terminal begin to heat up quickly. it seems like it's a short somewhere but I can't find it and I have no other wires but bare essentials hooked up.. im think that it could be the built in generator/alternator because it's pretty much the only other thing hooked up... anybody have this problem before or know anymore???

Ayuh,.... Heat, is a sign of Resistance,... Clean the wirin' ends to Shiny metal clean,...
 
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