Where'd the oil go

R

Roy

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114
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The boat is a 25 foot Chris Craft pocket cruiser. It was repowered by a Mercury certified shop with a factory new Mercruiser 5.0l MPI 260 HP. The 20 hour service was performed by the same shop at about 20 hours. At 54 hours the engine went into Guardian mode due to low oil pressure. A mechanic at the same shop checked the oil level and said it was 2 - 3 quarts low. So where did it go? Seems to me it had to go either into the bilge or into the water. Trust me it did not go into the bilge. I would have noticed that much oil in the bilge. So does that mean it leaked out of the oil cooler into the cooling water? If so was there a defect in my brand new engine? Did something happen during the install? Any thoughts?

Thanks.....Roy
 
The oil cooler is a good suspect. Was it new?
 
It was supposed to be. I paid for everything brand new because I wanted reliability. I didn't get it.

Roy
 
They'd stopped selling the 5.0 V8 by the time we bought a bored 5.7 called a "357" but ours has a power steering cooler and not an oil or fuel cooler. So, if it has an oil cooler, that's a logical suspect given that much oil has gone AWOL.

Is there any trace of water in the Oil Pan? Chocolate milkshake look on the dipstick? I hope that IF the cooler is leaking, like at a crack, the Oil Pressure is enough to force Oil into Water, but the Water (on the suction side of the Circulating pump) doesn't have the pressure to put Water into Oil.
 
Well j'd I was so angry when it happened that I took it back to Mercury certified shop that did the work. I didn't even look at the dip stick because at the time I didn't know it was an oil issue. The oil gauge never showed a problem. I only later found that out after the shop hooked up their computer and read the fault codes. After that they checked the dip stick and confirmed the loss of oil.

Roy
 
Do you know it in fact is fitted with an Oil Cooler? I'd need your Engine Serial Number to try and check.

Is it under Warranty?

If it was mine, I'd try to test the oil cooler just to verify it was the source of the leak, replace with new, and change the oil+filter. Maybe twice. I change my oil with a "sucker" so I'd be sure the Sucker was clean, then pull the oil out, pour into something clear and look for water. If none visible, I might just go with new oil and filter and run it. If I was suspicious, fill with "average" oil and filter, run a couple hours, change back to the super MerC stuff (the 25W-40 Blend and Quicksilver filter aren't crazy expensive at Walmart). And go boating.

I couldn't justify the price of the MPI. I liked the way our old 1996 5.7 TBI started, but once running the new 357-four-barrel does pretty well. Still, 25 more ponies would be fun. Tool Time! More Power!

I can only imagine your frustration! Let us know how this goes.
 
j-d, I appreciate your help. The only reason I say it has an oil cooler is because that's what they told me at the shop. Engine S/N is 2A183549.

Roy
 
Did you check all fluid levels when you got it back from the 20 hr service? Have you checked them since that day?

If there is essentially no oil in the bilge and you have not noticed a sheen in the exhaust wake or blue exhaust smoke, then this is almost certainly a serving shop error , mistakenly underfilling the crankcase to just over minimum level at which low-pressure guardian mode occurs under normal conditions. They probably intended to re-check dipstick after a quick startup to fill the (remote?) filter and oil galleys but never did that.

That was likely compounded by owner not checking fluids before startup. Plus it can be easy to get a false reading on the stick if it is not withdrawn, wiped clean and reinserted to finally be pulled out and read, plus plus new oil can be very hard to read correctly on the stick.

But the shop is never going to own up to this. Particularly ... if... the owner neglected to live up to his part of boat ownership responsibilities.
Strongly suggest you carefully double check anything done by a shop or other than by the owner.

And triple check anything done by the owner (us.) :)

New engines use some oil as rings and cylinders seat in , but nothing like 2 qts in 30 hrs and the 3 qts was likely an exaggeration.

-Just an opinion and do not mean to offend.
 
Every 5.0 or 305 I could find had serial numbers beginning in "0" (Zero). Many were "0M" so are you sure you got the Engine Serial? a MerCruiser has three serial numbers. One on the Drive, near the upper decal on one side. Another on the label decal in the middle top rear of the Transom Assembly, and one on the Engine. On newer engines, it may be a label/tag on the lower starboard side, near the block drain/knock sensor.
 
Sandy, I'm not offend at all. Check and double check is a lesson learned. BTW, I'm beginning to think your theory that the shop underfilled at the 20 may be correct. I did check the dip stick once and it was at the very bottom of the OK hash mark. Maybe normal consumption after that put the engine into Guardian mode. Also the shop owner seemed reluctant to try and find out what happened. He told me "run it" after they re-serviced the oil and filter.
j-d, I am aware of the T/A and drive numbers, and that number I gave you was right off the top of the engine. And forgot to answer last time - it is out of warranty.

Roy
 
I just found a different parts company with a Serial Number Search that says you have a 5.0, 5.7 or 377 MAG MPI Sterndrive. 1998 and newer, and they furnished a Part Number, of 4M4122LUV, and next to that is the 5.0 displacement size. So... Later today I want to try and figure out if it even has a crankcase oil cooler.

Can you tell me the type of Cooling System you have? My choices are Single Point Drain, Three Point Drain, or Seven Point Drain.

Looking like Sandy's right. Low oil out of the gate, fell to critical. He's the kinda guy when he says what's wrong, we might as well just go ahead and order the parts.
 
I'm afraid I cannot answer the drain question. I'm at work right now and unable to answer. I think those descriptions refer to draining the cooling water for winterization purposes. I winterized my boat by moving to Florida!

Roy
 
I Think it very probable that Sandy is right. Checking fluid levels and looking for leaks and weird stuff in the ER is just a part of normal boating. Always check after some work was done. I always asked what work had been done when I worked in a good trouble shooting shop years ago. Often found the problem there.

I still have a rule to check fluids multiple times after a change and put a wrench on every nut turned after the job is done and all tools and parts cleaned up. Every once in a while........
 
I'm beginning to believe it does NOT have an Engine Lubricating Oil Cooler. And that it DOES have a Fuel Cooling Module and a Power Steering Cooler. Wish I could check that from the parts lists I found by entering your Serial Number at https://www.perfprotech.com/mercury-marine-parts-catalog/searchserial?search=2A183549 but no joy.

You should be able to trace lines from your fuel rails down to the Fuel Module, and the Power Steering Pump down to the PS Fluid Cooler. If your 5.0/305 engine had a block-mounted oil filter, it'd be low on the port rear of the block. Pretty much opposite the starter on on the starboard side. But you have a Remote Oil Filter, and if you trace those lines, I think you will find them running to and from an adapter down in that lower port corner. And NOT to an Oil Cooler. But if there IS an Oil Cooler, for Engine Lube Oil, that's where it'd connect, and you'd find the cooler in line with the Fuel and PS Fluid Coolers.

The good news is you probably don't have any issue but the oil got low. As Sandy notes and Bruce agrees, we'll won't ever know how that happened. Be glad the engine flags it. Go Boating!
 
Bruce, As I've already mentioned that is a lesson well learned. I guess I put too much faith in a brand new Mercruiser and a Mercury Certified shop. Reminds me of what pilots say: An aircraft is most dangerous after it comes out of the maintenance hanger.

Roy
 
quote:
Originally posted by Roy
Reminds me of what pilots say: An aircraft is most dangerous after it comes out of the maintenance hanger.
Roy

Click to expand...

Made me think of an article linked here several years ago, maybe by Bruce, called Waddington Effect. https://blog.aopa.org/aopa/2014/01/14/the-waddington-effect/ This came from maintaining B-24 bombers back in 1943. Overkill maintenance was increasing down time.

I found the article liberating, B-24 pun there, but now I know I don't have to dismantle and reassemble my lawnmower every week. Just check oil, add gas, and go. Fix it when it needs it.
 
Interesting. I think the quote I mentioned was aimed at saying maybe the mechanic did not do something correct while the plane was in the hanger and thus put it in jeopardy during flight.

Roy
 
JD that was from Gregg.

Roy: The quick response from the shop to run it may mean he suspected missing oil was the problem. Since it shut down I dont think there is anything to worry about. I guess safety shutdown is something Merc got right.
 
The more I think about it the more I think it was shop error. Which actually is a good outcome because, if true, that means there is no defect in the engine after all, and I learned a valuable lesson.

My thanks to you and j-d for all the helpful comments.

Roy
 
Please go enjoy your boat, new engine and all, and let us know how you're doing.
 
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