oil pressure

[wdknox]

1995 7.4 bravo I <br />Remanufactured Long Block <br />Yesterday I started my engine for the first time, I only ran it for 5 to 10 seconds at a time, three or four times. The oil pressure on the gauge went up to about 20 psi max. Then I went back to check the engine and the oil filter gasket had blown and blew oil all over the place. I checked the oil lines to make sure they were right, put another oil filter on and the same thing happened again. After that I needed a break. I am getting ready to start trouble shooting the problem. Can someone please steer me in the right direction

 

[Wellcraft 89]

Re: oil pressure

Who did the rebuild? did you buy it from a rebuilder?<br />Could be a couple things!<br />Oil pump relief stuck <br />Spun bearing on crank <br />or plugged oil passages to the crank<br />Sometimes engine rebuilders don't chk the passages carefully enough and all the crud settles in there<br />Also you should always prime the oil system before starting a new rebuild unless you know that proper assembly lube was used.<br /><br />Rich

 

[wdknox]

Re: oil pressure

I bought it from International Diesel Ltd. Where would you start your trouble shooting

 

[Olds Eddie]

Re: oil pressure

It could be that the oil filter adapter has a stuck bypass valve, or no valve at all. You should check it visually with a mirror to see. Some high performance engines use an adapter plate that has no valve so that all the oil runs through the filter. Also it could have an oil filter gasket stuck to the filter base and it will not retain the gasket if there are two stacked together. As a note, if this is not a roller cam engine you need to not let it idle under 2000 RPM for the first 30 min. of operation to break in the new lifters and cam. Roller cams are not a problem.

 

[thunderroad]

Re: oil pressure

The first thing I'd do would be call the place who did the rebuild and tell them exactly what you told us in your first post and ask them what you should do. If for no other reason than to be on record as reporting a problem with an engine immediately. <br />My first thought has already been mentioned. An old filter gasket stuck to the base. I've had this very thing happen (on trucks) when that's the case.<br />Here's hopin it's something minor. good luck

 

[wdknox]

Re: oil pressure

I put the oil filter adaptor on myself and there wasn't an old gasket on it. The first thing I guess I will try is removing the adaptor from the block and install a filter there, that way I can eliminate all the hoses and the cooler. That will be first thing in the morning, I'll let you know what I find. I want to thank everyone for their replies, definitely some good information and advice.

 

[wdknox]

Re: oil pressure

I removed the adaptor that goes to the oil filter on top of the engine and installed an oil filter directly to the block. Cranked the engine for short intervals and did not blow the oil filter gasket. Not reading oil pressure but could be bad sending unit, going to install a local guage at that place to check the pressure. Now I have a question, the oil filter that blew the gasket was a automotive filter bought from autozone, does it matter if it is automotive or mercruiser. The one I installed at the block was also an automotive one but it was better quality (mobile one).

 

[Olds Eddie]

Re: oil pressure

I will risk the rebuke of all the marine mechanics but I have used a good quality auto filter on my SBC/Merc for years. Originally I used an AC but have switched to K&N as they have less restriction of flow. I have also used Fram racing filters.

 

[prockvoan]

Re: oil pressure

Been using Frams for years.

 

[Ralph 123]

Re: oil pressure

Oil filter study. A MUST read for all merc owners IMHO<br /><br /> http://www.oilfilterstudy.com/

 

[LubeDude]

Re: oil pressure

Originally posted by Olds Eddie:<br /> As a note, if this is not a roller cam engine you need to not let it idle under 2000 RPM for the first 30 min. of operation to break in the new lifters and cam. Roller cams are not a problem.

Please tell me that you primed the engine before you started it. and followed the above.

 

[Buttanic]

Re: oil pressure

Could be you connected the remote filter adapter with the inlet and outlet lines switched and if the filter had an anti drain back valve that could account for the low oil pressure and blown gasket

 

[wdknox]

Re: oil pressure

Ralph thanks for the link it has a lot of good info in it.<br /><br />LubeDude I did prim the engine before I started it. Got the loaner tool from autozone and used my own drill, flushed oil through the lines and the cooler and took the pressure sending unit off to make sure I had oil flow all the way to it.<br /> <br />Buttanic I am pretty sure I had the lines hooked up right and I double checked them after the first oil pressure gasket blew, but before I put the oil filter adapter back on I will definitely triple check it to be sure.<br /><br />Thanks to all that have replied you thoughts and ideas are very helpful.

 

[wdknox]

Re: oil pressure

OK Here is my fix. Wellcraft 89 hit the nail on the head. I change out the oil pump and that took care of the problem. I tried everything I could think of to keep from pulling the engine, but in the end thats what I had to do. Again thanks for all the ideas.