2006 Mercruiser 4.3L MPI V6 Oil Pressure Problem

[mrosales]

I have a 2006 Mercruiser 4.3L 220hp on a 2006 20ft Triton Deck boat. A couple of months after the first 10 hour oil change (done by Mercury shop), the engine would start hesitating at around 4000rpms and begin to loose RPMs. If I attempt to increase power, it would sputter some more and loose more rpms. The oil pressure drops to 20psi from the specified 40-45psi. After this occurred twice, the dealer stated that the engine had too much oil and drained some oil out. The engine worked fine for a couple of months and then it would repeat the same symptoms. This time the engine sputtered more than before and lost nearly all of its RPMs. The audible engine alarm came on as well and I barely made it back to the marina. At home, the engine oil was at FULL which is where the dealer left it at. I attempted to turn the engine on (with water ear muffs of course) and the audible engine alarm came on and there was some clacking which I assumed was the valves. I immediately turned the engine off.

The dealer looked at the engine and determined there was zero oil pressure and that the oil pump was dead. They replaced the "long engine block" and and head gaskets since it was still under warranty. This was in November of 2007. When I got the boat back, I was told to go through the gentle engine break in again and have the next oil change at 10 hrs. It ran fine for the first couple of hours of engine break in time. I put fuel stabilizer in the fuel tank and stored the boat for 2-3 months for winter.

March came around and after about several trips or about 7 more hours of engine time, the engine started sputtering and hesitating again this weekend and the oil pressure dropped back to 20 psi on my return trip to the marina.

I don't know if anybody has had any similiar experience with the Mercruiser 4.3L V6 MPI engine. Please help!!!

 

[Don S]

Re: 2006 Mercruiser 4.3L MPI V6 Oil Pressure Problem

Have you checked the oil lately?

 

[Bondo]

Re: 2006 Mercruiser 4.3L MPI V6 Oil Pressure Problem

Have you checked the oil lately?

Ayuh,.......

Or Ever for that matter........

 

[mrosales]

Re: 2006 Mercruiser 4.3L MPI V6 Oil Pressure Problem

Yes, the oil (and many other things) are checked everytime the evening before I go out on the water and it is always at the correct level (full). I also turn the engine on the evening before (with ear muffs + water of course) to be sure.

My father is a retired auto mechanic so I've learned and understand quite a bit on automotive engines. I am not saying this to be smart but to let you know that you are not talking to a dummy regarding combustion engines. I know how important it is to keep up the maintenance. This is the first boat I've ever owned so I am new to marine engines.

 

[JustJason]

Re: 2006 Mercruiser 4.3L MPI V6 Oil Pressure Problem

Just curious.... are ya checking the oil on the trailer...
Or are ya checking it on the water (hopefully relatively calm water)......
Idealy.... you should check it on the water.....

Alot of people store their boats bow high on the trailers, which makes the oil level appear low. So you add some, to get it up on the dipstick, But then once you put it in the water it levels out. And actually has to much.

 

[mrosales]

Re: 2006 Mercruiser 4.3L MPI V6 Oil Pressure Problem

The service shop manager at the Triton/Mercury dealer told me it was fine to check the oil on the trailer as long it was not in a very high/low bow position. When the engine block was replaced, the dealer, of course, put in the new engine oil and filter. The oil level has remained the same ever since I got it back from the dealer. There is no oil in the bilge that may have leaked to speak off. The bilge is nearly spotless clean. There are no traces of cooked/caked engine oil/grease on the outside of the engine if it may have leaked from the filter, case, etc.

I always look in the engine compartment when I turn the engine on the day before I go boating to see if anything leaks especially when the oil is circulating and under pressure. The exhaust from the engine is clean. There is no white/gray smoke being emitted from the exhaust which would indicate oil linking into piston chambers through gaskets/valves and burning with the fuel.