Where are the most likely places for a 5.7 to leak engine oil?

[LAC_STS]

I have a new 5.7 engine. It has about 50 hours on it.

The old engine was leaking oil and got the bilge pretty nasty. i cleaned some of it up but not anywhere close to all of it.

If there is just a little bit of water in the bilge I dont see any oil in the water. But if the bilge gets a inch or two of water in it I can sometimes see a little "ring" if you will of oil around the water line.

I have good oil pressure. I changed the oil at the first ten hours. When I checked it today it was just a hair under where it was before on the dipstick. I only had to put about 1/8th of a qt in it to bring it back to right at the top line on the dipstick.

so I will continue to monitor the level and I have tried to put one of those white oil abosrbing cloths down but I dont see anywhere where its actuall dripping down.

Where would be some good spots to look for oil on the engine?


Thanks

 

[Don S]

Re: Where are the most likely places for a 5.7 to leak engine oil?

Where would be some good spots to look for oil on the engine?

Look EVERYWHERE. There is no such thing as a normal place, or common place for oil leaks. Even if there was, your's probably wouldn't be there. Murphy ya know.

Clean it all up, then go for a ride and keep an eye on it and see where the oil is coming from. That is what us "professionals" have to do. There is no EZ Button or magic bullet for finding leaks.

 

[LAC_STS]

Re: Where are the most likely places for a 5.7 to leak engine oil?

Look EVERYWHERE. There is no such thing as a normal place, or common place for oil leaks. Even if there was, your's probably wouldn't be there. Murphy ya know.

Clean it all up, then go for a ride and keep an eye on it and see where the oil is coming from. That is what us "professionals" have to do. There is no EZ Button or magic bullet for finding leaks.

K thanks Don.

Do engines like this "burn" small amounts of oil? Or no? If I see any change on the dipstick does it mean oil is leaking somewhere, even if its a very small change?


Thanks again

 

[wanna-be]

Re: Where are the most likely places for a 5.7 to leak engine oil?

u prob have oil residue in bilge and the water loosens it. oil is lighter than water so any residue will form a ring. if u have anew block, the most likely leak will be the filter. did u change the oil? if so did you coat the rubber ring before installing the filter? u might also try tightening... only hand tight.

 

[littlebookworm]

Re: Where are the most likely places for a 5.7 to leak engine oil?

An engine with only 50 hours on it might be burning some oil, but more likely you have a small oil leak somewhere. You need to start with totally cleaning out your bilge. Use some Simply Greem or other safe liquid soap or cleaner. Make sure it can't harm waterlife if dumped overboard.Pull the fuse on your bilge pump, including the one which allows your pump to run with the battery switch on "Off." Put about two inches of water in your bilge from a hose. Pour in some cleaner and take your boat for a bumpy ride. That will mix the soapy water and clean out the oil stuck to the sides of the bilge. At the dock, reconnect your bilge pump, run it, and use the garden hose spray to wash down your bilge. Keep the alternator and starter dry. Wipe down the bottom of the engine and the bilge with toweling to the best of your ability. You want everything as clean and dry as you can make it. The take the boat for a short run. At the dock, with the engine off, start wiping down areas along the bottom and ends of the engine. Check especially: the area by the timing case/water pump, the area by the oil filter, the oil drain plug area, the area by the rear main seal, the hoses to and from the remote oil filter if you have one, the area by the dipstick, and any other area you can reach near the bottom of the engine. See if you can move either of the remote oil filter hoses or their fittings. If all this is clean and no more oil appears in the bilge, then you're burning some oil. If that persists, you've got a different problem to deal with. Remember, just a drop of oil in the bilge spreads out and looks like a mess. Hope this helps. Hy

 

[fishaman]

Re: Where are the most likely places for a 5.7 to leak engine oil?

I have exactly the same case, old engine leaked, installed new, now tiny film of oil when the water gets above half inch in the bilge. I believe I know exactly what is going on: in front of my engine there is a "limber" hole connecting the bilge with the space under the fuel tank. The oil film from my old leaking engine got deposited in that space, and there is no way to clean it completely. So when the water gets high enough to get in the hole, it brings back some oil residue from under the tank.

And yes, the new engine will burn some oil. I have changed it after the first 20 minutes, then after the 20 hour break-in time, that's what is recommended in the manual. It did use some during the first 20 hours.

 

[Eric 3.7LX Alpha 1]

Re: Where are the most likely places for a 5.7 to leak engine oil?

Sometimes a new engine will require some gaskets to be retorqued after running. (not head gaskets, but like pan, valve cover, manifolds, etc).

Check whatever paper work came with the engine or ask the company who did the work if it is necessary to be checked.

 

[Aloysius]

Re: Where are the most likely places for a 5.7 to leak engine oil?

Oil pressure and oil level are unrelated. Us inboard guys have oil leakage problems because of the steep angle of the engine..you can't depend on the dipstick for an accurate measurement. Often too much oil is used, and the crank hits the oil and throws it everywhere (windage). It's not uncommon for an engine to spit out 1/2 a quart of oil, then stop "using" oil. If the level drops to a certain level on the dipstick and stops, that's "full" for your particular application.

 

[LAC_STS]

Re: Where are the most likely places for a 5.7 to leak engine oil?

Oil pressure and oil level are unrelated.

So no matter how much oil you have the pressure will be the same?

I dont think so.

I get what your saying about having too much though. My engine looks pretty level when the boat is just sitting in the water which is when I check it. So Im pretty sure the dipstick should be accurate.

 

[Alpheus]

Re: Where are the most likely places for a 5.7 to leak engine oil?

Your oil can be low and as long as the pump is still picking it up your pressure wont change. Your pressure is not linear with the amount of oil in the pan...

PS

Do you get sick allot???

 

[Don S]

Re: Where are the most likely places for a 5.7 to leak engine oil?

If the oil level is over the oil pickup in the oil pan, and it isn't being aireated by the crankshaft or anything else because of the oil being hit by the crankshaft, then oil LEVEL is not your problem.

Rather you have an oil leak or not, only you can tell that. That's because you are there and can see the engine.

If your problem is the oil in the bilge, that oil probably moves throughout the bilge, under the gas tank, through small holes anywhere, stuck to other things in the boat etc. It will leach out forever. Especially when the water level in the bilge gets a little deeper than normal and moves it around.
Use some bilge cleaner, some oil absorbant pads or sheets, change water level in the bilges to get it all cleaned up.
You would be surprised at the the oil I have found in bilges when people change oil and drop the filter, or spill oil in the bilge, or .....................

 

[LAC_STS]

Re: Where are the most likely places for a 5.7 to leak engine oil?

Yea but if your oil gets too low then you won't have any pressure. So it is related. Maybe not so much when it's close to it's propper weather.

Sick? When I feel like it. Lol.

 

[LAC_STS]

Re: Where are the most likely places for a 5.7 to leak engine oil?

Will do Don. Thanks.

I didn't even think about under the fuel tank until.

 

[floyd mason]

I have a new 5.7 engine. It has about 50 hours on it.

The old engine was leaking oil and got the bilge pretty nasty. i cleaned some of it up but not anywhere close to all of it.

If there is just a little bit of water in the bilge I dont see any oil in the water. But if the bilge gets a inch or two of water in it I can sometimes see a little "ring" if you will of oil around the water line.

I have good oil pressure. I changed the oil at the first ten hours. When I checked it today it was just a hair under where it was before on the dipstick. I only had to put about 1/8th of a qt in it to bring it back to right at the top line on the dipstick.

so I will continue to monitor the level and I have tried to put one of those white oil abosrbing cloths down but I dont see anywhere where its actuall dripping down.

Where would be some good spots to look for oil on the engine?


Thanks

I have a 1989 5.7 260hp (350 chevy block) Mercruiser. It has an external oil filter mounted to the front right facing the engine (port side). Follow the lines from the oil filter back to where they connect to the block. On my engine just below where they attach there is a cover that covers where an oil filter would be if it was a car or truck engine. This cover is a little bigger in diameter than an oil filter has a hex shaped nut on the bottom in the center, 21mm fit the nut. A simple partial turn to tighten and the oil leak was gone. I think the cover gets a little loose from vibration after some hours of operation. It's hard to get to but it's an easy fix.

The valve covers and front timing cover are easy to inspect from the front of the engine. This place on the lower right side is a place that you have to reach down to feel the leak. It is accessible enough to get a wrench on it.