Maritime_Eng

So does anyone know if all Gen VI 502's came with the 11lbs spring? I have two 1998 502 MPI's in my Formula that I just bought and they are both low on oil pressure after a run.

Thanks
Don

warriorp

Hey guys - just wanted to say thanks for explaining the oil bypass valves. I am not an offshore guy, but run airboats in the same manner and I have the exact same issue detailed above on my zz502. I just replaced the cam & lifters, 1" spacer, gasket matched rpm air gap, 2" performance headers with DUI distributor and came across this post during the build.
Easy fix and logical - just wanted to say thanks. The airboat forums - no one has ever brought this up or been this helpful.

p.s. there is a 11 page link that was very helpful too, but i could not find it again.

jeffswav

Welcome to the site !! A lot of new people this week. Thats a great thread, like you said there is a more detailed one also. I had problems with my oiling also, I now have a bigger oil cooler and 12AN lines and fittings.

blue thunder

Airboats rock! Birds of a feather air boaters and offshore racers. Welcome warrior.

Rookie

iTrader: (4)

This also is a good one to read, and needs to be brought back up TTT every once in a while.
http://www.offshoreonly.com/forums/g...-hardware.html

warriorp

Thats the one - thanks guys

ezstriper

yes, great info...working on the same deal right now...have a question...have seen 2 part #'s listed for the 30lb valves...25161284 and 25013759...both available from GM....but which is correct ??? I had a post on this a week ago...same deal different people..different #'s....can anybody clearify ???Thanks Rob

ezstriper

also on the leaving center valve out ??? using remote filter/cooler..

Rookie

iTrader: (4)

I plugged mine the same as Strip did in his photo.

Question to engine builders, why would you put the 30# bypass in and not plug it? I want all of my oil going through my filter and cooler. My friends ZZ502 was destroyed in 10hrs when the original owner/builder left the 11# bypass in. If you are plugging filters and coolers I think you have worse problem than not having a bypass in.