mep803a odd oil leak help

[Scoobyshep]

I used to use CRC contact cleaner QD for leak detection spray the surface down blow it dry and see if it gets wet again

 

[jqc99]

Nice photos, thanks!

To me, I don't see a smoking gun of a leak in the center of the engine bay, nor on the engine itself. The other item that seems a bit odd to me is how high the stain runs on both sides of the enclosure, raising the question of where it is wicking from.

If it were me, I would pull the batteries, get some Dawn, and degrease everything, dry it off, confirm that the stain is gone, and wait. You might find that the source is somewhere else.

Side comment, I would fasten the batteries down. Loose batteries are in my experience a recipe for bad things.

All the bets,

2Pbfeet

I will take your advice and secure the batteries. When I had the originals, they were secured. Someone here (my apologies to who it was because I can't recall who) mentioned we could get away with these smaller batteries in warmer climates and I never got around to securing them. They start it with ease and cost WAY less. I ordered some dye and a UV source, so I'm going to clean it up again, including the exterior as you mentioned, and hopefully locate the source.

I used to use CRC contact cleaner QD for leak detection spray the surface down blow it dry and see if it gets wet again

I never thoiugh of using contact cleaner, but might give it a shot or I could try brake cleaner. I've used an engine degreaser in the past and I've also used simple green. It just kind of depended what I had on hand at the time.

 

[Scoobyshep]

I will take your advice and secure the batteries. When I had the originals, they were secured. Someone here (my apologies to who it was because I can't recall who) mentioned we could get away with these smaller batteries in warmer climates and I never got around to securing them. They start it with ease and cost WAY less. I ordered some dye and a UV source, so I'm going to clean it up again, including the exterior as you mentioned, and hopefully locate the source.



I never thoiugh of using contact cleaner, but might give it a shot or I could try brake cleaner. I've used an engine degreaser in the past and I've also used simple green. It just kind of depended what I had on hand at the time.

The reason we used it was due to the quick drying. we were able to find hydraulic leaks faster with it. Its less effective on weeping low pressure leaks but still useful.

 

[2Pbfeet]

I will take your advice and secure the batteries. When I had the originals, they were secured. Someone here (my apologies to who it was because I can't recall who) mentioned we could get away with these smaller batteries in warmer climates and I never got around to securing them. They start it with ease and cost WAY less. I ordered some dye and a UV source, so I'm going to clean it up again, including the exterior as you mentioned, and hopefully locate the source.



I never thoiugh of using contact cleaner, but might give it a shot or I could try brake cleaner. I've used an engine degreaser in the past and I've also used simple green. It just kind of depended what I had on hand at the time.

Just FWIW: In my experience brake cleaner (usually a mix acetone and some organics like pentane/hexane) can be pretty aggressive and may eat into the engine paint. I know the CRC brake cleaner dissolves the CARC. I think that Dawn, and Simple Green, are more benign, at least in my experience. The purple (lye) cleaners and engine degreasers, and at least some of the citrus cleaners are in between, and I only use them if I don't care about the paint.

If it were me, I replace the failing oil drain hose before cleaning the surfaces as the replacement process is likely going to have oil spills that hopefully diapers or pig mats will catch, but just in case, I would do it first.

All the best,

2Pbfeet

 

[Toolslinger]

I'll add that I occasionally use starting fluid to clean and dry for the same reasons the contact cleaner works. With the cranky, vintage, gas powered toys I have, I always make sure to have that in quantity... Contact cleaner is around, but usually a can at a time, and I always struggle to remember where I left it.

 

[jqc99]

I'll start with something begnin. Whatever engine degreaser I used previously apparently didn't harm the paint, but I'm not going chance it this time. This isn't some high end vehicle that you want to keep pristine, but I don't want to wreck the paint with something overly harsh when there are alternatives. I try to keep it looking good.

Because I'm ignorant on casting porosity, I did some googling on it and at some point GM had a recall for some blocks with porosity. One of the solutions was they coated the area with RTV. If, by chance, the dye doesn't find my leak, I may give the underside of the block a coating of it and see if that cures it since that's the only place on the engine that I'm finding the oil.

 

[Light in the Dark]

Are you 100% certain the return lines aren't seeping or leaking? You have had the top off and inspected?

This area looks wet (red)... this is why I am asking about the lines again. Red looks like it has something on the surface of the metal. The blue, to me, looks like the end of the leak (going from generator head side, and 'blooming' forward towards the radiator).



I would put closer visual effort into the crank side of the engine, top and bottom.

 

[Ray70]

In my mind I thought it looks more like fuel than oil as well, but hard to say from a distance.
Perhaps give the foam pad under the engine a squeeze with a paper towel and see if you can get any liquid out of it.
Are you using road diesel or dyed fuel?
check the color and smell, if you can get anything on the paper towel.
take a close look at the fuel return line going up to the front injector, see if it is damp anywhere.
But... the UV dye will be the tell-all. No signs of dye after running a while = not an oil leak and would point towards fuel leak.

 

[Light in the Dark]

In my mind I thought it looks more like fuel than oil as well, but hard to say from a distance.
Perhaps give the foam pad under the engine a squeeze with a paper towel and see if you can get any liquid out of it.
Are you using road diesel or dyed fuel?
check the color and smell, if you can get anything on the paper towel.
take a close look at the fuel return line going up to the front injector, see if it is damp anywhere.
But... the UV dye will be the tell-all. No signs of dye after running a while = not an oil leak and would point towards fuel leak.

It does look like a fuel leak, which is why I asked. If it was an oil leak the staining would be heavier, and typically catching more airborne debris due to thicker viscosity

 

[Ray70]

Yup, Exactly! I was in agreement with you and I also need to rephrase... that's the rear of the engine not the front ( I was still brewing daily coffee #1 at that time ) so I'd suspect a leak up top on a return line, pooling up on top of the head and dripping down, not the return line running up the front to injector #1
If you can't see up top with a mirror, try poking around with a paper towel touching on the head, see if you find any wetness.
This is yet another benefit to running dyed fuel. Red is a dead give away that it's fuel, not oil.

 

[2Pbfeet]

Given the recent emergence of this leak, the location of the stains, and the staining pattern, I would again (post #9 above) say that I really think that this is a diesel leak, not an oil leak.

If this was a proposition issue in the casting, you would probably always have had the issue.

All the best,

2Pbfeet

 

[Light in the Dark]

Yup, Exactly! I was in agreement with you

Great minds and all

 

[jqc99]

Are you 100% certain the return lines aren't seeping or leaking? You have had the top off and inspected?

This area looks wet (red)... this is why I am asking about the lines again. Red looks like it has something on the surface of the metal. The blue, to me, looks like the end of the leak (going from generator head side, and 'blooming' forward towards the radiator).

View attachment 939192

I would put closer visual effort into the crank side of the engine, top and bottom.

It is dry at the red arrow and all along the top of bottom horizontal ridge (and the ridge above it). That whole side of the engine is dry, as is the generator side. You are correct, it is "blooming" at the blue arrow. It's actually doing the same thing towards the generator head, but not as much, which could be because the trailer it sits on proabbly isn't perfectly level. It's the weirdest thing. The entire engine is dry except for the underside.

In my mind I thought it looks more like fuel than oil as well, but hard to say from a distance.
Perhaps give the foam pad under the engine a squeeze with a paper towel and see if you can get any liquid out of it.
Are you using road diesel or dyed fuel?
check the color and smell, if you can get anything on the paper towel.
take a close look at the fuel return line going up to the front injector, see if it is damp anywhere.
But... the UV dye will be the tell-all. No signs of dye after running a while = not an oil leak and would point towards fuel leak.

I have squeezed the foam and was expecting a lot of oil, but there wasn't. I got a coating on my fingers, but really not that much. I'm using road diesel, so color doesn't help, but the oil, or whatever it is, has no diesel smell at all. I've checked the fuel lines, both supply and return. All dry.

It does look like a fuel leak, which is why I asked. If it was an oil leak the staining would be heavier, and typically catching more airborne debris due to thicker viscosity

When I get a good amount from the underside of the engine and I'm wearing latex gloves, it feels like oil. It has a more viscous feel to it than diesel. The generator sits in a clean outbuilding more than it runs so that could explain the lack of debris.

Yup, Exactly! I was in agreement with you and I also need to rephrase... that's the rear of the engine not the front ( I was still brewing daily coffee #1 at that time ) so I'd suspect a leak up top on a return line, pooling up on top of the head and dripping down, not the return line running up the front to injector #1
If you can't see up top with a mirror, try poking around with a paper towel touching on the head, see if you find any wetness.
This is yet another benefit to running dyed fuel. Red is a dead give away that it's fuel, not oil.

I'll feel around the top of the head to check for wetness.

Given the recent emergence of this leak, the location of the stains, and the staining pattern, I would again (post #9 above) say that I really think that this is a diesel leak, not an oil leak.

If this was a proposition issue in the casting, you would probably always have had the issue.

All the best,

2Pbfeet

I would have thought so too, but maybe because it has such low hours and if the porosity isn't that bad, it took this long to make it through the block? I don't know enough about porosity in casting if that could be the case.

 

[Ray70]

With casting porosity it can take a while to emerge. My brother had a jeep wrangler 4.0L back in like 93', bought it brand new and had it for a couple years before a strange oil leak developed at like 20K miles. They eventually replaced the motor under warranty saying it was a porous casting.
The only possibility that comes to mind for you would be that maybe the glyptal coating inside the block has been protecting it, but has recently gotten breached?
Other thing is that if the bottom of the block was indeed porous it would leak all the time regardless if it's been running recently or not, but I don't think you really know if the leak is worsened when running or not, do you?
I guess next step is to get that dye in there. That should shed light on things quickly.
I'd say throw it in and start it quickly, just a few seconds to mix it in, then let it sit a day or 2 and look for it underneath first.
If nothing, then run it a while ( preferably at night or in a dark place ) and keep checking it. you'll know it if it comes out!

 

[Ray70]

Because I'm ignorant on casting porosity, I did some googling on it and at some point GM had a recall for some blocks with porosity. One of the solutions was they coated the area with RTV. If, by chance, the dye doesn't find my leak, I may give the underside of the block a coating of it and see if that cures it since that's the only place on the engine that I'm finding the oil.

I wouldn't suggest just slathering RTV on the block while crossing your fingers.
Lets take it a step at a time and see what's going on for sure.
If it happens to come down to an issue with the block itself there are much better cures than RTV, but let's cross that bridge if we come upon it.

[/QUOTE]

 

[Light in the Dark]

Because I'm ignorant on casting porosity, I did some googling on it and at some point GM had a recall for some blocks with porosity. One of the solutions was they coated the area with RTV. If, by chance, the dye doesn't find my leak, I may give the underside of the block a coating of it and see if that cures it since that's the only place on the engine that I'm finding the oil.

I wouldn't suggest just slathering RTV on the block while crossing your fingers.
Lets take it a step at a time and see what's going on for sure.
If it happens to come down to an issue with the block itself there are much better cures than RTV, but let's cross that bridge if we come upon it.

[/QUOTE]

This. If you had a casting flaw, like others said, it would be constant leak, and you would be visually able to find the origin. The paint would be removed in a manner pointing to the flaw.

 

[jqc99]

With casting porosity it can take a while to emerge. My brother had a jeep wrangler 4.0L back in like 93', bought it brand new and had it for a couple years before a strange oil leak developed at like 20K miles. They eventually replaced the motor under warranty saying it was a porous casting.
The only possibility that comes to mind for you would be that maybe the glyptal coating inside the block has been protecting it, but has recently gotten breached?
Other thing is that if the bottom of the block was indeed porous it would leak all the time regardless if it's been running recently or not, but I don't think you really know if the leak is worsened when running or not, do you?
I guess next step is to get that dye in there. That should shed light on things quickly.
I'd say throw it in and start it quickly, just a few seconds to mix it in, then let it sit a day or 2 and look for it underneath first.
If nothing, then run it a while ( preferably at night or in a dark place ) and keep checking it. you'll know it if it comes out!

Other than perriodic mainetenance runs, it actually sits most of the time as it only has 159hrs on it and I've had it for 9 years. When I've had outages and it runs for hours at a time, I don't notice any increase in leakage, although I haven't been specifcially watching for it because it's been awhile since we've had an outage.

 

[jqc99]

Last night I did a visual inspection of the top of the head with a mirror, then poked all around with a paper towel. All dry. Lately everytime I'm around the genset, I'll open it up and look over it all again hoping to see something I'm just overlooking. It's frustrating to have such an odd leak and not be able to find it. The dye and UV source came yesterday. They are calling for rain here tomorrow and Sunday, but I'm hoping to be able to still do the dye test this weekend.

 

[Light in the Dark]

If after you dye the oil and evaluate, if nothing jumps out, dye your fuel.

 

[jqc99]

If after you dye the oil and evaluate, if nothing jumps out, dye your fuel.

Will do! And if nothing comes from dying the fuel, the only liquid left is coolant, but that's the wrong color I'm seeing. Well, my wife tells me...