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Low oil pressure after hard run

L

lpoulets

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Just had my '94 Carver repowered with 2014 5.7 classic (carburetor). They both have about 20 hrs on them. Stbd engine specs are right on the money. However, port engine drops oil pressure to about 10 psi after a 1/2 hr run at 3300 rpm. (Stbd pressure is about 40 psi). I replaced the factory shipped oil with SAE 40. Engine is running at about 155 degrees. I used a infrared thermometer on the oil filter canister and read 245 degrees. The port engine oil filter temp is less than 180. Very frustrated. Any ideas???
 
10 psi at idle is within spec but I'd still have a bit of concern over it....I'd start with a mechanical gauge to verify the issue. I know the newer capt's choice 5.7's have engine and gear oil coolers so would hope the classics do as well....and 2x on 245 deg F being too hot for the engine oil...
 
Yes, that's what the crusader distributor said "within specs". However, & it's a big however... the stbd engine is also new and it doesn't drop below 40 psi. I guess I have to get a mirror out and look around the stbd engine to see if it has a cooler somewhere. I didn't notice one. Where would the oil cooler get the oil from, would it be in series with the lines from the block to the remote oil filter assembly?
 
U coolers are pretty much restricted to big blocks....

YES, the oil cooler should be in the raw water line and have hose connections to from the remote oil filter head and/or the block, depending upon how they plumb the small blocks...
 
Checked other engine. Just transmission cooler too. That one has good pressure & good oil temp. So, what's the consensus? Should I install a oil cooler, or would I just be masking an underlying problem?
 
I'd say installing an oil cooler for the engine would be masking the real issue....I'd suggest getting the IR gun on heat exchanger (inlet and outlet - both closed and open sides) and the exhaust elbows....the idea is to gain insight into how much heat is being generated and how its being shed.....a final item to check is to make sure the seacock feeding the raw water pump is fully opened and the strainer lid is tight....just a 'tiny leak' can induce enough air into the raw water stream to make a big reduction in its cooling capacity...
 
I've never had hot oil like this. I'd be inclined to pull the plugs on both engines and rotate the cranks with a rachet and compare. Could be this hot engine has low bearing clearances. Without plugs, it should turn without a huge effort.
 
With so little of the boating season left, I would adds a can of Lucas oil stabilizer and take it easy. That stuff works wonders.

Jeff
 
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