Jt29- you might be able to get the bypass out with the engine in the boat, but it would be very tough to install correctly as the valve needs a few hits with a sharp punch to install it more securely. You could however block this passage with the engine in the boat with a plug, someone should know the size, and run a synthetic media filter. I personally think the 30psi bypass valve has its advantages for the recreational boater.

It's my understanding, according to Dennis Moore's book "Big Block Chevy Marine Performance" , that all "marine version" BBC GenVI motors come with the 30lb bypass valve in them.
This was in fact what I found when I bought my marine 502 long block three years ago!

Liquid,
It's the port engine, so there's
stringer issues, concerning access.

I've been wondering about the
neccessity of this valve, due to the
same valve being installed in the
remote filter/ oil cooler thermostat housing.

Scott,
here's my plan:
After I'm done for the season,
and boredom has set in,
the engine will come out, check for any abnormalities,
if nothing is found, I'm going to swap engines
from side to side. ( I too, have been wondering
about the electrical bugs)
and see if the readings move from side to side.

jt

jt29olhp500s, I found that a 3/8" bolt will thread right into the old bypass. If you can find some type of weight with a hole in the center you can make a "slide hammer" and it will come right out. You can do it in the boat if you have good (great?) access to the pad. I've left the center hole in all three of my blocks empty because I use a remote oil cooler.

Re: Results of changing oil bypass springs on Gen VI 502
 

can this valve be changed with the engine in the boat or do i have to pull it

Re: Results of changing oil bypass springs on Gen VI 502
 

Heres a picks of the valve .My Remote adaptor and screwdrive in passage

Re: Results of changing oil bypass springs on Gen VI 502
 

I plug mine :drink:

http://www.offshoreonly.com/forums/s...t=500efi+built

Re: Results of changing oil bypass springs on Gen VI 502
 

What did you use and how did u plug it?

Re: Results of changing oil bypass springs on Gen VI 502
 

Wow old thread!

Just to update my problem:

Ended up with swapping out everything in the system and found nothing wrong so I changed my electrical sources for both engines Larger gauge wire. This solved all my electrical problems except the strange readings on the red-line gauges so I swapped them out to mechanical oil gauges and have been at ease since. I would like to see higher idle pressure after a run on the engine that ate a lifter but I have to assume my bearing tolerance must be different on that side after the rebuild. It runs great and stays within 10lbs or higher per 1000rpm's so instead of going anal over a 5lb fluctuation between engines I just decided to enjoy the boat :D

Next time I need to rebuild I will learn how to set up tolerances myself or do the build with a friend that knows how to set them up right! Enough of trusting my stuff to a "get them in and out" budget shop!

Re: Results of changing oil bypass springs on Gen VI 502
 

looks like a fishing weight :drink: