Mercruiser 7.4 MPI oil leaking

[BigDog98]

So I have been noticing some oil in my bilge every now and then after it sits for a few days. The weird parts is that every time i pull the dipstick it shows different reading. Fist it would show ok range then it would show add range. To me is seems like its engine oil based on the brownish color. I traced the hoses that go from the oil filter and they all seem good. What else should i look for and check? Please any help will be greatly appreciated. Here are a few pictures i took of the bilge in the front and in the back.

 

[Bondo]

What else should i look for and check?

Ayuh,.... A rust through hole in the oil pan,.....

 

[alldodge]

Fist it would show ok range then it would show add range.

That just says your loosing or burning oil, does it ever come back up to full?

 

[BigDog98]

Ayuh,.... A rust through hole in the oil pan,.....

Well I did notice rust under the oil pan. How urgent would that be to repair? Can I survive the season with it and just monitor and add oil as needed ?

 

[BigDog98]

That just says your loosing or burning oil, does it ever come back up to full?

Yeah if I slide the dip stick in and out it will show full and then sometimes it shows low. Weird part is that one one side of the dipstick it would show full and on other it would show low. I'll take a picture of it later today.

 

[alldodge]

Yeah if I slide the dip stick in and out it will show full and then sometimes it shows low. Weird part is that one one side of the dipstick it would show full and on other it would show low. I'll take a picture of it later today.

One side being low and the other high in most cases means your low. The stick goes in and is sounded by oil, it gets pulled out and if one side of the stick comes next to more oil on the way out (inside the tube), that side will show more.

Your oil is in the bilge, you don't want the oil to be pumped out into the water. Ya need to find the leak

 

[BigDog98]

Added a quart of oil dip stick showed full , started the engine let it run to iloperating temp rechecked and was in the middle of ok and add

 

[Bondo]

Well I did notice rust under the oil pan. How urgent would that be to repair? Can I survive the season with it and just monitor and add oil as needed ?

Ayuh,.... Who knows,... It's rust, a tiny hole can become a Huge hole is seconds dependin' on how badly it's rusted,......

You could be loosin' a quart in 10 hours, 'n suddenly drop all 5 quarts in minutes,.....

 

[BigDog98]

checked the oil pan with a camera , no rust , just chipping paint

 

[BigDog98]

Does the oil pan have a drain plug ? Maybe its leaking or loose ?

 

[Bondo]

Ayuh,.... You just looked with yer camera, ya shoulda seen it,.....

 

[Pete104]

How's P/S fluid?

 

[BigDog98]

Ayuh,.... You just looked with yer camera, ya shoulda seen it,.....

I did , for several minutes. No signs of leaks or anything.

 

[BigDog98]

How's P/S fluid?

I checked that as well and found one leaky hose but the fluid is pink not the brown color like in the bilge.

 

[Pete104]

I checked that as well and found one leaky hose but the fluid is pink not the brown color like in the bilge.

I get that but it mixes really fast with other residual oil that would be "normal" from oil changes and so on. ATF has alot of detergent properties.

 

[alldodge]

Its probably just leaking from a seal, oil sending unit or down the valve cover if its blow by. Suggest looking and feeling around for what is wet and try to trace back

 

[Bondo]

Suggest looking and feeling around for what is wet and try to trace back

Ayuh,.... Actually, you'll be tracin' it Up,.....

No wind in a boat, oil, like water, flows downhill,....
When ya find oil, keep lookin' higher til ya see no more oil,... ya just went past the leak, look a little bit lower,....

 

[alldodge]

Oh good grief your kidding right? Trace it back to where it came from :facepalm:

 

[Bondo]

Oh good grief your kidding right?

Ayuh,....

Yer doin' a Great job in here AD,....

No offense,...

 

[BigDog98]

Found the oil pan plug and its all good. I was told from a dock neighbor that switching to synthetic can cause a leak if conventional was used before. I just switched to synthetic 25w40 oil this year. Not quite sure what oil was used before because this is my first year owning the boat. I purchase some engine cleaner and will thoroughly clean the engines so hopefully that will help me find the leak easier.