Radiator to Transmission cooling line?

Needed some input... On my '01 XJ I replaced my radiator w/one f/ FFD about 3 months back. So far so good but an issue may have arisen.

While doing some work under my rig I noticed a drip of coolant on the transmission cooling line... one come off the radiator to my OE transmission cooler. So this weekend while doing some maintenance I think I found where the leak was coming. The worm clamp was a bit loose on the top line coming out of my radiator (see pic)... this pic was taken after I tightened the clamp and wiped all the coolant off. The coolant was seeping out where the hardline is clamped.



After snugging up these clamps I started thinking... should any coolant even be coming f/this line? I assumed this should only have transmission fluid and NOT coolant going through this part of the radiator. Should I be worried? Could there be a leak in the radiator allowing coolant to mix w/transmission fluid? I could use some input here... Thanks.

Looks like your radiator cap is leaking. How else would there be coolant on your airbox?

That's possible...

I think there is a very small stream of coolant w/the system pressures up and 'spraying' if you will... but again, I could be wrong. Not always easy to diagnose where a leak is coming from. The reason I didn't think it was my radiator cap is that the coolant you see on the air box and under the radiator cap could have got there as I removed the radiator cap to check the coolant level and it was very well sealed and had some pressure on it... even though the engine was 'cold' when I pulled the cap.

Makes sense. But I still think your leak is up higher than the trans cooler line. Your electric fan looks a little green also.
What kind of radiator did you get?

FFD Aluminum Radiator and Dirtbounds Triple Electric Fan kit...

Back to my original concern... should there be coolant in that line (circled in red) or only transmission fluid?

Just trying to narrow down any problems to work on next... ha

No, there should only be transmission fluid in that line. If there is in fact coolant in it there is a leak in the cooler circuit inside the radiator. Check the transmission fluid for coolant and the coolant for transmission fluid.

I'd look elsewhere for leaks.. like the rad cap.

That's what I thought...

I'll keep looking for the leak... such as the cap. I believe I have a near-new cap siting on my work bench that was removed w/the last leaking Champion Radiator that this FFD unit replaced.

91to99 said:

Looks like your radiator cap is leaking. How else would there be coolant on your airbox?

Click to expand...

Good eyes, I missed that, but I noticed coolant under the cap on the radiator!

I believe you guys are correct... Popped the hood last night when I got home to see coolant all around the bottom of the cap, transmission line, air box, etc...

Didn't have time to fix it last night, but at least it appears to be the source of the leak. Have to find my Stant HD cap that is laying in my garage somewhere and replace the one currently on the Radiator and see if that works.

You might also check the tubing going to the
overflow tank, to make sure it isn't clogged
or pinched.

Runnin'OnEmpty said:

You might also check the tubing going to the
overflow tank, to make sure it isn't clogged
or pinched.

Click to expand...

Bingo... we have a winner here!!!

Not that the overflow tubing was clogged, but it was loose enough at the connection going into the radiator that it was leaking w/the cooling system pressured up. I added a simple hose clamp where that tubing goes into the radiator filler neck and think my troubles should be fixed (at least for now)

Just have to give it some time...