Oil in bilge

[Blue2005]

Hello everyone,

I recently discovered I have an oil leak somewhere and I can't seem to find out where it's coming from. Some background info - The engine is a 2005 5.0 GXi-E and the boat is run in saltwater. I was out on the boat all Sunday and I didn't notice anything strange. I pull the drain plug after leaving the ramp and I only see clean water coming out. Fast forward to my house, I flush the engine and everything seems good. Oil pressure is still good at this point. I'm done for the day.

In the morning, I notice a good amount of oil in the floor that had drained from the drain plug. I get into the boat and notice the bilge with a good amount of oil. At this point I check all the fluid levels and everything looks okay. The engine is not missing any oil - and it definitely looks like engine oil in the bilge. So I clean the bilge, run the engine for a 15 minutes and I can't see any oil leaking from anywhere. I turn it off and let it rest for s few hours. I come out and I see the same puddle under the drain plug.

I'm stumped on where the oil leak is coming from. The engine has 330 hours and I was planning on changing the oil in the next 20 hours or so. The oil filter looks to be fine. Any help would be awesome at this point.

 

[Fishhead-1]

Very good chance oil pan pin hole usually around the dipstick tube on very bottom. Get clean rag with brake clean or whatever to cut oil and reach under pan and clean it very good. Start on muffs and warm engine shut off and reach down under pan see if it comes back. Happened to a lot of us in salt.

 

[Blue2005]

Very good chance oil pan pin hole usually around the dipstick tube on very bottom. Get clean rag with brake clean or whatever to cut oil and reach under pan and clean it very good. Start on muffs and warm engine shut off and reach down under pan see if it comes back. Happened to a lot of us in salt.

I'll check as soon as I get home. In the event that this is the cause, how bad is it of a fix?

 

[Fishhead-1]

Remove drive, remove engine pull pan off and replace. Could use oil absorbent pad under it to finish out season and make it a winter project if leak is minimal yet. I painted pan with a 2 part epoxy after installing dipstick tube. Good luck hope it's not it. Double check the oil pressure safety switch for leakage or sender

 

[Dave-R]

Before you pull the engine, check to see if the banjo fitting on the oil pan to dipstick is loose. Don't over tighten it as it has an o-ring seal. And just as an afterthought, check the PCV valve if the engine is equipped with one. Wipe everything down clean, then run it and find the wet spot. Are you sure it's not power steering fluid? Dave-R

 

[Blue2005]

Alright...so I was able to see under the engine and it looks like the pan is rusted around the plug and it's leaking oil through there. However, the leak is very small and hasn't affected the engine oil level. I know that I have to pull the engine to replace the pan but I'm wondering if I can continue using the boat with this small leak until I can pull the engine.

I'm trying to get quotes for this job but from what mechanics charge it looks I'm gonna have to do the job myself.

 

[further]

I had a similar situation with my 4.3gs. It was my first season with the boat and found the leak right after i was done replacing manifolds, risers, full tune up, etc and really wanted to get the boat splashed. Really didn't want to pull the motor sooooo I know its not the right way to do it but I figured I would try. I removed all of the oil with my pump, let it sit and any remaining drip out. Cleaned and dried the area as well as I could. Got under the pan with some sandpaper and removed as much of the surface rust as I could. Then I sprayed the oil pan with rust converter stuff (don't remember exactly which but I think it was a rustoleum product), patched around the plug with JB Marine (this only works if you make sure the area is completely clean and dry) and I topped it all off with rubberized spray paint (also don't remember exactly what it was but similar to rustoleum leakseal).
So that was May of 2014; almost 3 full seasons of fairly regular use. I probably just jinxed myself but it's held up pretty good so far.

 

[bruceb58]

I wouldn't run it again until you changed the pan. If you want to roll the dice, it's only a $4K engine if you need to replace it when you run out of oil. You feel lucky?

If you do run it and wipe out the engine, consider going up to a 5.7L.

 

[Blue2005]

I wouldn't run it again until you changed the pan. If you want to roll the dice, it's only a $4K engine if you need to replace it when you run out of oil. You feel lucky?

If you do run it and wipe out the engine, consider going up to a 5.7L.

Ya, I hear you. I'm gonna buy an engine hoist and just remove the engine altogether and have it replaced. I got 2 weeks to do the job before Labor Day Weekend

It'll be nice to swap it for a 5.7 but I can't drop the cash on that now. I'll post some pictures when I remove the engine. Is there a specific part # for that oil pan? I've been looking but it seems like there might be different oil pans.

Thanks for the replies guys.

 

[gbeltran]

Before you pull the engine, check to see if the banjo fitting on the oil pan to dipstick is loose. Don't over tighten it as it has an o-ring seal. And just as an afterthought, check the PCV valve if the engine is equipped with one. Wipe everything down clean, then run it and find the wet spot. Are you sure it's not power steering fluid? Dave-R

I second the power steering fluid check. The return lines harden and then don't seal well. I have replaced these lines on two boats recently, in both cases the owners asked to help find an oil leak. It was clean and wipe down the engine, run it, didn't find anything, but happened to notice the belt jumping/squealing, p/s fluid was low, so looking at those lines found leaks at the cooler. Hoses were old and hard and just put on with squeeze clamps. New hose and some worm gear clamps and back in action. I would definitely be checking those.

 

[Blue2005]

I second the power steering fluid check. The return lines harden and then don't seal well. I have replaced these lines on two boats recently, in both cases the owners asked to help find an oil leak. It was clean and wipe down the engine, run it, didn't find anything, but happened to notice the belt jumping/squealing, p/s fluid was low, so looking at those lines found leaks at the cooler. Hoses were old and hard and just put on with squeeze clamps. New hose and some worm gear clamps and back in action. I would definitely be checking those.

I got under the engine with a mirror and I was able to see the oil leak coming from the rusted oil pan around the oil plug. A shop down here in Miami quoted me $3000 for the job - no way it's worth that much. So I'm going to be pulling the engine next week and replacing the pan myself.

 

[Fishhead-1]

Maybe some one else might be able to chime in, I used two part epoxy primer and brushed it on liberally on the underside of pan especially around that tube area so rust can't get started. Don't know if there could be something better to use that can deal with the heat generated from pan.

 

[gbeltran]

I got under the engine with a mirror and I was able to see the oil leak coming from the rusted oil pan around the oil plug. A shop down here in Miami quoted me $3000 for the job - no way it's worth that much. So I'm going to be pulling the engine next week and replacing the pan myself.

Sorry to hear it's a more complex job.

 

[loco]

I had the same, and it was indeed the rusted oil pan. Tuned out there was also bad rust on the engine mounts, and they needed replacing. I ended up replacing the entire engine, and the new came with a plastic sump, which seems to make total sense in a boat!

Certainly feel your pain though - a ?50 part needing a whole engine pull. Nightmare.

 

[Fishhead-1]

I had the same, and it was indeed the rusted oil pan. Tuned out there was also bad rust on the engine mounts, and they needed replacing. I ended up replacing the entire engine, and the new came with a plastic sump, which seems to make total sense in a boat!

Certainly feel your pain though - a ?50 part needing a whole engine pull. Nightmare.

Is that plastic pan on a 5.7 vp?

 

[Blue2005]

So quick update guys. I ended up pulling the engine, easier than I thought, and replaced the oil pan. No more oil leaks and it's running perfect.

All in all, I wasn't able to go out on Labor Day weekend but the job itself was pretty easy.

Thanks for all the suggestions.