Offshoreonly.com - Assembling 8.1L 502

Offshoreonly.com (https://www.offshoreonly.com/forums/)

- General Q & A (https://www.offshoreonly.com/forums/general-q-20/)

- - Assembling 8.1L 502 (https://www.offshoreonly.com/forums/general-q/385816-assembling-8-1l-502-a.html)

I recently rebuilt my 496 and used a high volume pump. I used an arp oil pump shaft to get rid of the plastic collar that holds the stock shaft on the oil pump. Just good insurance imo either pump option you go with

Quote:

Originally Posted by lmannyr (Post 4929897)

Are there any downsides to a high volume. From my short "google university" search, not required for essentially stock engine. The high volume oil pump also takes MORE power to run and there is some potential for the oil pump shaft to shear??

Looking for AC Delco or GM unless there is another Brand (Melling?) thats is more recommended.

Imannyr,

Melling 10778 Melling Performance Oil Pumps | Summit Racing

This is the one I bought for my rebuild. for the record, we removed ALL bypass valves. All the oil goes through the filter and cooler. I see 40+lbs at idle and ~60lbs at nearly anything above idle.

Thanks. Brad.

Quote:

Originally Posted by Brad Christy (Post 4929914)

Did you replace the bypass valves with plugs or leave them open?

Mr brad has a 496 8.1l. A gen vii. Not a v/vi 502 8.2l. Just pointing that out, i do not know the gen vii oiling system.

Quote:

Originally Posted by SB (Post 4929923)

Mr brad has a 496 8.1l. A gen vii. Not a v/vi 502 8.2l. Just pointing that out, i do not know the gen vii oiling system.

Im building out a 496/8.1 GEN 7. Bored 30 over…so 502 now?

Quote:

Originally Posted by SB (Post 4929923)

Mr brad has a 496 8.1l. A gen vii. Not a v/vi 502 8.2l. Just pointing that out, i do not know the gen vii oiling system.

SB,

I guess I assumed OP had just mistyped one or the other, since 8.1 is a 496 and 8.2 is a 502.

Thanks. Brad.

Quote:

Originally Posted by lmannyr (Post 4929924)

Im building out a 496/8.1 GEN 7. Bored 30 over…so 502 now?

Imannyr,

Not a shameless plug at all, but….

BBC Oil Filter Blockoff Kit

Just to give you an idea what we did.

For the record, we took out the bypass in the center, and blocked off the side port. Not really sure how it all works as OEM, but this works great. To be honest, I don’t really see a need for the bypass, given how often we change our oil, compared to an automotive engine.

Thanks. Brad.

Quote:

Originally Posted by Brad Christy (Post 4929926)

how much? I like it. I have 2 bypass valves though. So would need to block 2 ports of same size.

Quote:

Originally Posted by lmannyr (Post 4929932)

how much? I like it. I have 2 bypass valves though. So would need to block 2 ports of same size.

Imannyr,

You have to really consider how much modification you are going to do. When I rebuilt mine, we scrapped a LOT of what made it a Merc engine. My entire oil system is custom, with the filter mount on the transom.

All we did was remove the center bypass and plug the other one. We also blocked off the two NPT block ports that are next to the filter socket.

Thanks. Brad.

Quote:

Originally Posted by Brad Christy (Post 4929934)

VP simply has a cap that screws onto the filter adapter covering the entire filter pad. The 2 side threaded ports next to the filter pad is what is used to filter and cool the oil.

Decided to put in two 30 pound bypass valves. I had to think about this but thought it was best to increase the bypass PSI verses completely blocking them off. I'm not worried about the filters since oil changes are done regularly. If the oil cooler gets clogged, then the engine is SOL. The flow is....Side port--->remote oil filter--->oil cooler--->return to the second side port.

A picture of the filter pad and side ports with the 2 bypass hoes (center and off center on filter pad) is on post #3.