Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   oil pressure problem on 454 (https://www.offshoreonly.com/forums/general-q/277135-oil-pressure-problem-454-a.html)

strega 06-17-2012 08:00 AM

End result!!

http://i236.photobucket.com/albums/f...K/IMG_2152.jpg
http://i236.photobucket.com/albums/f...K/IMG_2153.jpg

wannabe 06-17-2012 08:44 AM


Originally Posted by strega (Post 3710915)
After a cool down it did increase to a point then dropped off. I have since stripped the engine and found that all the big end bearings were shot, 3 had spun and one had hammered itself out to the thickness of a piece of paper!! i know believe all this started when i hydraulic the motor after springing a leak in one of the manifolds.

Oh, I didn;t realized you hydrolocked the motor. Did you do a leakdown test of the oil pressure after?

Those bearings are cooked BTW

Wannabe

1BIGJIM 06-17-2012 08:49 AM

Now you need to find the cause of the problem. When this happens metal shavings will be everywhere. I have seen them in lifters, valve guides, imbedded in piston skirts, and so on. Make sure every oil passage is cleaned twice. Make sure you get a new oil cooler also and make sure the oil hoses are clean.
Since not much will be left, time to build a stroker engine.:cool:

strega 06-17-2012 10:04 AM

It's getting the crank reground, new pistons, new rods, new cam, new lifters, new oil pump and pick up and am gonna flush the hell out of everything I am keeping.

Was hoping to flush the oil cooler. Do you not think it can be cleaned?

stroker would be nice, but would kill my Alpha drive I think!!

strega 06-17-2012 10:07 AM


Originally Posted by wannabe (Post 3710958)
Oh, I didn;t realized you hydrolocked the motor. Did you do a leakdown test of the oil pressure after?

Those bearings are cooked BTW

Wannabe

Strangley after a cool down I managed to get 60psi, but I can see by the debris in the pick up that it was struggling. the pick up was blocked solid causing the pump to bypass!

Raylar 06-17-2012 11:55 AM

This time use the Melling 10778C oil pump and make sure to have the pickup tack welded on the pump cover, do this carefully without a ton of heat so as to not damage the pump.
Also make sure the oil pickup is set up about 3/8" to 1/2" from the oil pan bottom when assembling.

Replace the cooler! Replace the cooler! Replace the cooler!

When having the crankshaft reground, have them mag it for cracks or serious flaws, straighten it first and then micropolish the journals after finsish grinding. Obviously balance the full rotating assembly.

Take the time to make sure the oil lines from the adaptor, to the oil filter and thru the cooler and back to the block are plumbed correctly so as to not restrict the oil flow and over heat the oil.
Make sure the shop installs any oil by-pass vlaves correctly and as they were engine was originally installed.

Use a good high wear package conventional oil for 2-4 hour breakin and then go to a good 20-50w performance oil.

Check the main line straightness and have the block aligned bored or honed to correct any problems there with straightness.

Make sure the machine shop doing all the block work knows, uses and understands the correct bearing, end play, rod fitment, piston, ring clearances and such for a marine engine versus automotive application and that they check them during short block assembly and don't just assume they are ok because of machining values and new rods, pistons, rings new bearings and such !

Make sure the engine is assembled with a good engine assembly lube and that is is properly oil primed before starting.

The most critical time on a fresh new machined and equipped engine is at the first startup. If things are not right here, they go bad very quickly and the result is usually a junk engine! Problems here tend not to fix themselves!

Hope everything goes well on the new engine. best of luck!

Best Regards,
Ray @ Raylar


All times are GMT -5. The time now is 12:01 PM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.