Whining noise when starting

Stelder

Cadet
Joined
May 29, 2016
Messages
17
When starting up the boat (3litre gm omc cobra) I'm hearing a whining sound, it's not the belt it's coming from behind the engine,
It seemed to have started when a mounting bolt on the starter broke but I have fixed the broken bolt,and noise is still happening ?
Any ideas on what to look for?
 

VE8EV

Petty Officer 2nd Class
Joined
Sep 5, 2012
Messages
109
Maybe a piece of something that broke off inside the bell housing?
 

Stelder

Cadet
Joined
May 29, 2016
Messages
17
If something broke off I would think it would make a grinding noise,I'm thinking it maybe the starter not completely disengageing .
Going to give it a run tomorrow and try and figure it out?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,083
It seemed to have started when a mounting bolt on the starter broke but I have fixed the broken bolt,and noise is still happening ?
Any ideas on what to look for?

Ayuh,..... Welcome Aboard,..... My guess is, If ya pull the starter back off, 'n look at the teeth on the ring gear, yer gonna see 'em all jagged, worn, 'n chipped,.....

It no doubt happened as the broken bolt started to loosen before it broke,....
The alignment of the gear teeth was thrown off, causin' damage to the ring gear,.....

The Good news is,... Ya can fix it for Nothin',....
The ring gear can be driven off the flywheel with a brass punch, throw it into the oven, heat to 500?, pull it out, 'n drop it back onto the cleaned flywheel, Backwards,...
Flip it over, 'n wear on the other side of the teeth,...

Bad news is,.... Ya gotta pull the motor to get the flywheel off,...

A brand new ring gear can be had at any auto parts store, maybe $50. bucks,...
 

Stelder

Cadet
Joined
May 29, 2016
Messages
17
Pulled starter and had it bench tested and lubed starter is good,reinstalled it and still making squealing sound backed off mounting bolts a bit and noise was not as bad so my next step will be getting some more shims and trying that,hopefully that cures it.ring gear looks good also.
 

Stelder

Cadet
Joined
May 29, 2016
Messages
17
Ok so this is what I did,I went and bought 2new mounting bolts so I go and put the long one in 3/8" x around 4" perfect,then go to put short one in and new 3/8"
X 2" doesn't fit,3/8" is too small so I put in a regular bolt 7/16" ,I also put on a home made support bracket on front of starter,installed all original shims tightened
Everything up and now works great no more squealing ,not sure what exactly fixed the problem ? Just glad it worked out:))
I would like to put proper short bolt in but everywhere I go says it should be 1 7/8"long x 3/8" diameter,
Why is mine 7/16" diameter? Maybe previous owner had it drilled and taped ??
 

Bondo

Moderator
Staff member
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Apr 17, 2002
Messages
71,083
Why is mine 7/16" diameter? Maybe previous owner had it drilled and taped ??

Ayuh,..... That would be My guess, as it didn't start out like that,....
 
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