Is an OMC flywheel the same as a mercruiser?

[stang32]

Same size motor.5.7ltr
Also is the flywheel for a 4.3 liter the same as a 5.7 thank you in advance

 

[jtybt15]

Engines are GMC. All components are interchangable with like engines. Don't know about 5.7 and 4.3

 

[j-d]

This page should help. Basically, every GM displacement uses a different flywheel, and those flywheels may be one of two diameters.

http://www.michiganmotorz.com/flywheels-c-32_44.html

So it shouldn't matter if the application was OMC, MerC, Volvo-Penta IF you get the Displacement, Year, and Diameter right.

What engine do you need a flywheel for, and which diameter? I might have access to some used parts.

 

[D. Andrews]

Also remember that the flywheel is an important part of the rotating group of your engine and the new one may not be balanced exactly to match your engine and might throw the engine balance out. If you can use the original one that came with your engine that would be the best choice. Why do you need to replace it?..........D..........

 

[Sandy]

Consider also, I believe the flywheels for a particular size marine engine are likely different size diameters for I/O's vs I/B's , plus whether any ring-gear offset is forward or aft depends on forward or aft mounting of the starter.

Disclaimer: My boats marine engines were always purpose-built with flywheel from the mfgr., so I have no experience in having to determine a correct FW .

 

[jtybt15]

The flywheels are exactly the same except for either one piece or two piece rear main bearing cap. There are two different diameters, 12" and 14". That should tell you how fast the cranking speed is. All different style starters are basically the same. The nose cone determines how far off-set to match the diameter of the flywheel.

The only other difference has been whether the engine is internally balanced(small block) or externally balanced(big block).

 

[stang32]

thanks guys, the old flwheel had a chipped tooth, i had a spare flywheel which i installed but afterwards relized there were many different part #s. i got lucky, it cranked the engine & the engine runs smooth as silk

 

[alien1952]

all you needed was a new ring gear, not a whole flywheel