Main bearing cap bolt attached stud?...

[daydreamer1252]

Replacing a Mercruiser 2.5 120 hp. with a rebuilt OMC 2.5L block. Attaching all the Mercruiser stuff to block. The OMC crank bearing cap uses a bolt with an attached stud (maybe for an oil pump pick up tube support?). Will this affect anything in the Mercruiser version negatively? I can't see what it would be but this my first of these to build up and use, don't want any nasty surprises because of incorrect assumptions!
Thanks for the help

 

[Fishermark]

Re: Main bearing cap bolt attached stud?...

I would think that you would need to use whatever mount is there for the engine you are using. In other words, use the oil pick up from the OMC engine and don't worry about what the Mercruiser used. And yes, I would say the stud is for a support for the oil pick up tube.

 

[daydreamer1252]

Re: Main bearing cap bolt attached stud?...

Thanks fishermark!
The only parts that are of OMC origin is the basic block and head bought it already rebuilt and have no OMC "accessories" to add onto it. That is why I ask. Don't want disturb the rebuilder's work if not needed. I could always remove a bolt from the Merc and install and re-torque if need be.

 

[Fishermark]

Re: Main bearing cap bolt attached stud?...

You bought it rebuilt already? Is there an oil pump installed on it? A pick up assembly?

 

[daydreamer1252]

Re: Main bearing cap bolt attached stud?...

No, nice bare block and head all new pistons and rebuilder's tag still attached all wrapped in plastic. No oil pump or pick up assy attached.

 

[Fishermark]

Re: Main bearing cap bolt attached stud?...

Well, if it were me... I would buy a new oil pump and then use the pick up tube assembly from the Mercruiser. You could just use the complete old oil pump and pick up from the Mercruiser.... but for a few dollars more, a new oil pump is good insurance. Good for peace of mind if nothing else.

How is the pick up assembly from the Mercruiser mounted? Is it simply a press fit in the oil pump with no tab to attach it to the main cap? If that is the case, I would also certainly tack weld the pick up to the pump. Then, as long as the stud is not in the way you should be fine.