Riddle me this...Riddle me that.... Where is all my oil at?????

[rndcomp]

THE BILGE..... That's where!!!!!

Now the question is why.

I have a Merc 170 (1987) with FWC and everytime I take the boat out and run it for a couple of hours, the bilge fills up with oil. This would probably explain the slight knocking that I am hearing (see earlier post). My question is, what is causing me to lose this much oil into the bilge???? Can be as simple as a drain plug that is not there. I doubt it, because it only leaks when the engine is running.

I do know that there is a problem with the front cam seal leaking, which is causing me to leak coolant. Is there a chance that the other seal is also bad which is causing me to lose oil.

Please help. I am ready to scrap this boat because everytime I fix one issue, another comes up. Yes, I know.... this is the story of boat owenership, however, it would be nice to be able to enjoy the boat a couple of time without fear of it breaking down on me.

Looking forward to someone's reply.

Thanks!!!!

 

[Don S]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

Leaky front or rear oil seal, leaky pan gasket, leaky valve cover gasket, hole in the pan. Hard top say, clean it all up and run it and LOOK, FEEL, use flashlight, mirrors, whatever. We can't even see it let alone tell you whats leaking.

 

[plassiter1]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

I have the same engine and also a mysterious oil leak.

after a cruise, oil in the bilge.

couldnt find it.

after running in neutral at 3200 rpm, i found it was leaking from the oil pressure sending unit.


so finding any oil leak isnt always easy. Take don s. advice, go slow, flashlight, paper towel and mirrors.

hoping its not your cam seals.

 

[95yj]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

If you're dumping that much oil, and you have lifters knocking, it's probably a pressure leak. Like stated earlier, check around the oil filter, the mounts and sending unit, etc. Most everywhere else that there's oil pressure, even with a missing plug, it will be an internal leak and leak back into the pan. Bad seals and such will usually make a mess over time, but won't dump a lot of oil quickly.

 

[rndcomp]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

OK, so I have done some looking around and have found that there appears to be a gap on the right side of the timing cover. If you look at the below diagram, and please note that I am assuming that the blue circle represents where the rotor/stator would be (sorry, I am not a mechanic so bear with me). If the blue circle assumption is correct, than at the tip of the red arrow is a 1/4" gap and there appears to be a missing bolt, as well as a bolt that is not all the way tightened. I can also see pieces of the gasket as well.


What I would like to know is if this is an area where oil actually exists in the engine, and if so, is this is a likely cause of my oil leaking into the bilge. I also want to know if the oil pan is directly below this as well, because if so, I am assuming that the oil pan gasket will need to be replaced.

Thanks so much for all of the advice!!!!!!!!!!!!

 

[Don S]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

You have an external leak, LOOK for it, don't just guess where it might be and start fixing good parts.
LOOK and find the leak, then FIX it.

 

[rndcomp]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

OK, let me be a little more specific, I checked the engine over with a inspection mirror, both running and at idle. Most of the oil that I found was coming from the front side of the engine so that is where I focused my search on. As I said before, I am not a mechanic and I don't really know what I am looking for. I saw no real signs of oil leaking in the back part of the engine, so I assumed that the rear seal was ok.

Next, I started the engine and watched for an oil leak. Since I am on muffs, I don't really want to rev the engine, nor do I really want to shove my head next the turning rotor. I did see some small amount of oil leaking from the area described in an earlier post. However, since I also have a leaking from cam seal, there is also water coming out of the front of the engine.

I am NOT guessing as to what I have found, but I am also NOT a mechanic and am looking for some guidance. I am sure this would be much easier process if the engine was out of the boat and I could scrub it all down and walk under it with a flashlight, but to be honest I am doing the best that I can.

Either way, regardless of whether or not this is the cause of my leak, my gut tells me that something is wrong here. There is a bolt that is not all the way in, and another bolt that is missing, as well as a 1/4" gap between the timing cover??? and the block. I am not guessing about that.

Thanks.

 

[Zeusdafreak1]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

I would clean the engine with degreaser. Get everything clean. Start motor with muffs. Rev to around 2000 RPM and watch. You may have to do it twice to be sure you pinpoint the exact area leaking. I would then tighten the bolt and replace the one missing. Make sure they are torqued and redo above. Degrease, etc. and see if the leak changed at all. Good luck.

 

[rndcomp]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

Thanks for the advice, I will do this tomorrow.

 

[summit800x]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

I had a similar problem on 1997 4.3. It turned out to be a cracked plastic timing chain cover. The oil leak was coming from the area of the front center of the oil pan that made it look like a pan gasket but in fact turned out to be the timing chain cover.This kind of a leak is a fluke form all the research I have done.
Good Luck,
Bob

 

[Don S]

Re: Riddle me this...Riddle me that.... Where is all my oil at?????

I had a similar problem on 1997 4.3. It turned out to be a cracked plastic timing chain cover. The oil leak was coming from the area of the front center of the oil pan that made it look like a pan gasket but in fact turned out to be the timing chain cover.This kind of a leak is a fluke form all the research I have done.
Good Luck,
Bob

He doesn't have a 4.3, he doesn't have a plastic timing chain cover. He is not looking for your leak, he needs to find his leak.