2008 sea ray slx 6.2

KEERAE

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Sep 13, 2018
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1
Anyone in the forum know why when I rev past 4rpm that my oil pressure goes below 25 and the annoying sound of limp mode and decreased speed happens. Ive asked a Sea Ray mechanic and he said its normal with the 6.2 litre bravo III
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
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51,400
welcome aboard

not normal

plumb in a mechanical oil pressure gauge to see what your oil pressure really is (not what the electric gauge is telling you )

if your oil pressure is actually dropping, you may need to pull the motor.

four reasons oil pressure drops
you do not have enough oil in the sump and you are drawing a vortex
you have a crack in the block in the lifter valley
you have worn or damaged bearings
your oil pump is damaged
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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even a fully blocked oil filter will simply open the bypass and provide full oil pressure..... right up to the point the unfiltered oil burns out the bearings
 

RaceCarRich

Petty Officer 1st Class
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May 31, 2015
Messages
234
I think a partially blocked (not enough to open bypass) filter can cause lower pressure. Not all bypasses open at same pressure differential so it’s a cheap and easy test.
 

RaceCarRich

Petty Officer 1st Class
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May 31, 2015
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234
Oil filter was optional on ‘55 Chevy V8. They weren’t 300K mile motors but they weren’t burning up bearings at every turn. Prob looser tolerances than now but still.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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51,400
Oil filters were optional going back to the 235.

The 216 was a dipper motor

However in the late model V8, the oil filter bypas is only 11psi, so any restriction more than 11psi and the valve in the block opens

The filter has a 30 psi relief

More than 40 psi differential and the filter collapses
 

RaceCarRich

Petty Officer 1st Class
Joined
May 31, 2015
Messages
234
I wouldn’t bet money that every filter brand bypasses at same psi. I’ve seen and heard about plenty of collapsed filters but many were on race cars where the block bypass was intentionally plugged. I have heard of but never personally seen a collapsed filter in a street car. I’ve read lots of stories about street cars with low oil pressure due to filter that were resolved with a filter change. Can’t hurt to give it a try before pulling the motor.
 
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