What is leaking and where is it coming from?

SOMD-JeepFan

SOMD-JeepFan

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Joined
Nov 6, 2018
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Location
Hollywood, MD
After running my SE (4 cyl) until things warmed up, I believe that I have found my leak, but I am not sure what fluid it is and where it's coming from. The fluid is accumulating just above the oil pan before it drips. It seems like transmission fluid, but I've noticed that I am losing engine coolant somewhere. Attached are some pictures to show the area from where it's leaking. If you look at the picture where I used the black light, you can see the fluid building up (yellowish-white dot in the middle of the pic).

90687

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What color is the fluid?

Reddish should be trans fluid.

Those connections on your trans lines next to it appears to have a little corrosion on it.
 
This one seems pretty tough to answer.

To me, it looks like the yellowish-white dot is some kind of light reflecting off something not usually between your camera and the rest of the engine.

The hot pink stuff from the black light would probably depend on whatever was mixed into some fluid that could be leaking.
 
JEEPCJTJ said:
This one seems pretty tough to answer.

To me, it looks like the yellowish-white dot is some kind of light reflecting off something not usually between your camera and the rest of the engine.

The hot pink stuff from the black light would probably depend on whatever was mixed into some fluid that could be leaking.
Click to expand...

The white dot is the leaking fluid. The pink is just the reflection off the hose from my light. You can also see the drip forming in the second picture.
 
OK now I understand the white dot. Man was I distracted by that big white reflection.

Unfortunately I'm not sure what it is. I'd probably touch it and check if it's slippery between my fingers. Transmission fluid is generally more slippery than coolant.
 
JEEPCJTJ said:
OK now I understand the white dot. Man was I distracted by that big white reflection.

Unfortunately I'm not sure what it is. I'd probably touch it and check if it's slippery between my fingers. Transmission fluid is generally more slippery than coolant.
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It's definitely slippery, but I can't tell if it is coolant or transmission fluid. I know that I am losing coolant somewhere as I've had to top off the radiator in the past. My overflow jug is low again, so I may have to top it off again. I may spray some degreaser on the engine to clean up where it's leaking, so I may have a better chance on figuring out what is going on.
 
I use the zerex hoat coolant, G0-5, I think. To me it seems kind of more orangeish where the trans fluid it more reddish.

@Boinked might be onto something with the freeze plug leak.
 
Boinked said:
I would be willing to bet that is a freeze plug leak.

The green oxidation on the lines is from an electrolyte. (water based fluid)
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I never knew what those plugs were on an engine until now. Thank you. I found a way to monitor the closest freeze plug to where I was seeing the fluid building up. Once I top off the radiator, I will run the Jeep again to determine if the fluid is coming from that freeze plug or somewhere else. It also appears that I may have a transmission leak as I am seeing orange(ish) fluid from this leak, but I also have dark red fluid accumulating on the skid plate under the transmission. My work is never done. Anyone in the Southern Maryland area want to get together? ;)
 
X2 to a freeze plug issue.

The red fluid accumulating on the skid is your transfer case fluid.
 
tworley said:
X2 to a freeze plug issue.

The red fluid accumulating on the skid is your transfer case fluid.
Click to expand...

After climbing around underneath my Jeep, I found that one of the transmission pan bolts is missing, so the red fluid may be coming from the transmission. I will check to see if the bolt snapped or if it was just left out by the previous owner. I guess I will drop the pan to replace the filter and gasket along with replacing the missing bolt. At least I am getting to learn my Jeep.
 
There is one bolt on the 42RLE trans that is supposed to have sealant on it when installed. I don't know if the 3 speed auto has that also, but others here may know. @Jerry Bransford , do you know?
 
MountaineerTom said:
There is one bolt on the 42RLE trans that is supposed to have sealant on it when installed. I don't know if the 3 speed auto has that also, but others here may know. @Jerry Bransford , do you know?
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That is true about the 42RLE. This is out of the FSM. When I did mine I didn't look at the bolts as they came out to have noticed which one had the sealant on it. My best guess based on the unclear FSM instructions it's the second bolt from the front on the driver's side of the pan. I applied sealant around the first three bolts just to make sure.

42RLE Bolt Seal Instructions.JPG
 
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Do you know if that applies to the 3 speed auto in the OP's Jeep?

I don't know anything about the 3 speed.
 
Boinked said:
I would be willing to bet that is a freeze plug leak.

The green oxidation on the lines is from an electrolyte. (water based fluid)
Click to expand...

Thank you, Boinked for pointing me in the right direction. Unfortunately, as you can see in the images I went a little too aggressive and replaced the three freeze plugs on the side of the block and now one of the new ones leak. Will the brass expand over time and seal the leak or do I have to redo the process on the leaking plug?

IMG_4225.JPG


IMG_4224.JPG
 
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SOMD-JeepFan said:
Thank you, Boinked for pointing me in the right direction. Unfortunately, as you can see in the images I went a little too aggressive and replaced the three freeze plugs on the side of the block and now one of the new ones leak. Will the brass expand over time and seal the leak or do I have to redo the process on the leaking plug?

View attachment 95296

View attachment 95297
Click to expand...

I don't believe that the brass will expand and seal.

You might be better off just replacing it. Maybe @ac_can chime in.
 
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