another stuck motor- omc 4.3 1990

CamaroMan

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Trying to free a motor thats stuck. Pumped a cocktail of Atf/Acetone 50/50 into cylinders yesterday. Removed crank pulley and will try fab up a bar to screw into damper -

whats the possibility something in the back it that stuck? If i could move the prop a hair in gear wd that eliminate an outdrive issue? Whats different between removing an omc outdrive than merc?

thanks - any tips welcome!
 

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Scott Danforth

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the first thing you did was pull the drive, correct?

plenty of info in the DIY stickies including vids on pulling a mercruiser drive
 

CamaroMan

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is this sand in the motor? omc cobra

Helping a guy out with a 90 omc 4.3.. kinda knew something was stuck but never before have I seen something like this..

What on earth is this and how does so much of it get in there?? Rest of motor is clean as a whistle - Also - can I put on any gm risers and connect them to the elbow or do I HAVE to use omc ones?

And are both the ujoint bearings the same part?

thanks
 

CamaroMan

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No Title

scott - nope, just tried rotating it using the crank pulley bolt holes - soaked in a acetone overnight, no go..

pulled heads today - have a peak at what I found in the hole - (started a new thread)
 

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Bt Doctur

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Thats what happens when water sits in a cylinder for a while
Yes, you dont need the omc type, Barr,Sierrs, Osco, etc will all bolt up to the engine , you just have to connect to the exaust
Yes , same part for both U joints
 

CamaroMan

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Thats what happens when water sits in a cylinder for a while
Yes, you dont need the omc type, Barr,Sierrs, Osco, etc will all bolt up to the engine , you just have to connect to the exaust
Yes , same part for both U joints


That much crud? what on earth rusts so much? almost like a kid went and deliberately put sand in there. Could a crazy amount of backwash )assuming exhaust flappers are no-go) allow so much sand to go up and into exhaust valve?

Its the rear stbd that had the most by a long shot - maybe they were fooling around??
 

Bondo

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Could a crazy amount of

Ayuh,.... Yer causin' a crazy amount of Mod work,.....

Post yer OMC questions in the OMC forum, not the Merc forum,...
'n there's No reason for multiple threads about the same problem, with the same motor,....

Please read, 'n follow our postin' rules, 'n guidelines posted at the top of the main forum page,....

Thank you,.....
 

Scott Danforth

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Most likely the exhaust valve was open and insects such as mud daubers built a nest

There is a reason bore scopes are an important tool.

Regarding your manifold question. Volvo, OMC, and Mercruiser have different y-pipe locations. Get manifolds and risers for your application
 
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