HELP! Reman Mercruiser 5.7L - oil in bilge

[twarner4574]

Ahoy all. I just had a mechanic (who provided and installed my reman engine last year) change the engine oil a week ago to prepare for launch day...which was yesterday. Boat ran fine in the driveway during pre-launch test. No leaks, all good. Launched boat at my marina, and when I got a little more than halfway around the docks on the way to my own I noticed my oil pressure gauge was reading no pressure. Tapped it a couple times, no change. Made it to my dock to park it, and noticed the motor running slightly rough, but not "missing". Was making a kind of slapping sound. Turned motor off after tying onto dock. Opened engine compartment and found really dark oil in the bilge and none in my engine. Dipstick had no oil on it. I didn't have a light, but I had a mirror to look under the engine as best I could at the time. Oil plug looks to be in place. FYI...I'm no mechanic by any means at all. Motor has 37 hours on it total since replacement. Mechanics phone is conveniently off as he is away for Memorial day. I'm wondering where and in what order it is that I should begin looking for where the oil may have come from, and what steps I should take to test. Again, I'm no mechanic and have only the most basic of tools. I'd appreciate any help.

 

[Bt Doctur]

If it was not leaking at home and then leaked check for drain plugs, drain hoses
Refill engine and start motor looking for leakage.clean the bilge and place a sheet of cardboard under the engine to help locate the area

 

[Fishermark]

I would suggest touching nothing at this point. Let the mechanic look at it so he can fix it and see what (if anything) he did to cause the problem. You might take your mirror and see if the oil filter is still in place or is leaking. If you want to protect yourself - it might be a good idea to take a few pictures of whatever you find that is wrong. (Just sayin' !)

 

[twarner4574]

Thanks Gents. I'll grab some clean up towels and motor oil and see if I can determine where it's coming from. Hopefully it's something stupid like a loose plug or oil filter as mentioned. Is launch weekend always just "debug weekend"? Seems to be something needs attention on launch weekend or Holidays every year! Must be Murphy's law. :facepalm:

 

[Scott Danforth]

Ahoy all. I just had a mechanic (who provided and installed my reman engine last year) change the engine oil a week ago to prepare for launch day...which was yesterday. Boat ran fine in the driveway during pre-launch test. No leaks, all good. Launched boat at my marina, and when I got a little more than halfway around the docks on the way to my own I noticed my oil pressure gauge was reading no pressure. Tapped it a couple times, no change. Made it to my dock to park it, and noticed the motor running slightly rough, but not "missing". Was making a kind of slapping sound. Turned motor off after tying onto dock. Opened engine compartment and found really dark oil in the bilge and none in my engine. Dipstick had no oil on it. I didn't have a light, but I had a mirror to look under the engine as best I could at the time. Oil plug looks to be in place. FYI...I'm no mechanic by any means at all. Motor has 37 hours on it total since replacement. Mechanics phone is conveniently off as he is away for Memorial day. I'm wondering where and in what order it is that I should begin looking for where the oil may have come from, and what steps I should take to test. Again, I'm no mechanic and have only the most basic of tools. I'd appreciate any help.

You changed oil, and now you have a leak. My first guess is the old oil filter gasket was still stuck on the motor when you out the new filter on. Would be ok for about 5 minutes before the gasket spits out. It happens.

If so, you are SOL with your mechanic as it wasn't anything he did

The slapping noise you heard is your motor eating itself from being run without oil.

You should have keyed off the moment you saw zero on the oil pressure gauge.

As BtDoctur indicated. Clean everyting, re-full with oil, and look for the leak. My first guess is oil filter gasket. Second is a loose oil filter

 

[Rick Stephens]

If I read correctly, the mechanic did the oil change. On him if the filter is the source. Don't touch anything!

 

[twarner4574]

Yes Rick, the mechanic did the oil change, not I. He's going to look at it this morning. I'll let everyone know what the issue is when I hear back from him.