Water in oil & low oil pressure. Diagnosis and prognosis?

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mvweebles

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Joined
Mar 21, 2019
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Location
United States
Vessel Name
Weebles
Vessel Make
1970 Willard 36 Trawler
A friend with a 15-year old sailboat with small Volvo turbo (around 45hp). Housing on oil cooler (raw water) ruptured. Cooler was replaced (cooler alone is $2700!!!!). I guess it's difficult access so install was difficult. He took it for a brief test run around harbor - after around 45-mins, oil pressure dropped from 55 psi down to 25 psi. Apparently has some additional exhaust smoke and some oil in exhaust. He know has emulsified engine oil, and oil level is low.

Any thoughts on what damage was done? My advice is to bypass the factory oil cooler with a generic online one and isolate that problem. Then change engine oil a couple times and see how it runs. How to dry out a wet engine? Any other ideas I can pass along?

Peter
 
Disconnect the oil cooler and pressure test it in place, either raw water or oil side. I would check the coolant for oil and level. Might be a head gasket leak. Was it running smooth otherwise?

Ted
 
Boat sat for about a year, but am told it was running smoothly prior. Owner brought it from San Francisco to Ensenada for work - a 500 nm run. Was not run much when oil cooler rupture was discovered (Pic attached)

Thanks for the tip. 969618334.jpg
 
$2,700 for an oil cooler, gotta love Volvo…
 
$2,700 for an oil cooler, gotta love Volvo…
Right? He tells me that was a discount off msrp. Shipped from Netherlands.

I suggested finding an online cooler and putting it in his raw water intake line. I think I paid less than $300 for one a few years ago when I replaced one for my hydraulic fins. Would need to have longer hydraulic lines fabricated, but easy here in Mexico.

Peter
 
If it just lost oil pressure yes I'd suspect the cooler. But there are a couple of comments made that suggest possible other problems.
1) more smoke. Just losing oil pressure should not cause smoke.
2) Water in the oil. Generally oil pressure is higher pressure than heat exchanger water pressure so leaks push oil out, not so much water in. I've had this failure on a Velvet Drive (of course they run higher pressure), and it just pumped oil out until the drive dropped out of gear but I found no evidence of water getting in.

I'd be worried that the combination of these to factors could suggest a head gasket was blown. Of course my mind tends to think of more drastic failures anytime something goes wrong! But you might want to check to be sure before just changing the cooler. If the engine is fresh water cooled have you checked for oil in the coolant as well?
 
Is the cooler raw or jacket water cooled? My 2 cents worth --

Bypass the oil cooler by connecting in and out water and in and out oil lines. Change the oil & filter 3 times, running the engine no more than 30 seconds or so between fills. Change oil & filter a 4th time and run for 5 minutes or so until warm. Once the oil is free of any water showing up, pull the valve cover and thoroughly clean the area with Sea Foam or equivalent.

Run until hot watching carefully for more water, oil pressure, leaks etc. Then make 100% sure the engine and new cooler check out before putting the cooler back into circuit. If it doesn't return it for credit or a new one.

Good luck to your buddy.
 
Water in the oil makes it easier for oil to get past the rings and the valve guides, causing smoke. Smoke could be steam.
Water in the oil usually doesn't ruin the bearings or rings unless run for a long time. It takes awhile to work the water out of the crankcase even with oil changes. The oil filter can catch and store about an ounce of water, depending on it's installation.
Several companies make replacement oil coolers for a lot less than Volvo. New small engine oil coolers I'm aware of usually go for less than $500. Leaking heat exchangers can usually be repaired or retubed by a radiator shop.
 
Thanks for all the great feedback. I've passed along. I'll update later in the week.

Peter
 
Water in the engine oil is almost always a head gasket or cracked head or block. Any info on the engine temp gauge ?? Overheat ?
As somebody said the oil pressure , PSI, would be more than the raw water PSI. Oil would go out the exhaust with the raw water. That's in the oil cooler.
It almost looks like a freeze up on the old cooler to push that metal out like that.
 
Here's the culprit - looks like the new oil cooler shipped from the Netherlands was actually a rebuilt oil cooler that hadn't been rebuilt.

Peter

Volvo Oil Cooler.jpg
 
Gosh it looks like a Craig's list unit. Did he get it direct from Volvo or get it via Internet shopping claiming it was a new OEM?
 
Gosh it looks like a Craig's list unit. Did he get it direct from Volvo or get it via Internet shopping claiming it was a new OEM?
I'm not sure what he thought he was buying. I originally thought he was buying from a Volvo distributor, but he mentioned it was supposed to have been a rebuild. I don't know him well and figured I didn't understand in the first place, or he didn't.

He's apparently found a replacement tube bundle that he's picking up today for $650 and will use the housing from the Dutch unit. Combination of shady parts and Volvo pricing means he's into this oil cooler something over $3k in parts alone.

Thanks to all. Definitely a cautionary tale on a couple levels.

Peter
 
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