Transmission oil cooler valve?

[purple_duckk]

I had some transmission cooling issues and I thought the transmission oil cooler might be plugged so I removed the coolant lines from the radiator side and it seems to flow coolant from the surge tank out no issues. The radiator seems to be flowing out to it no issues either and the engine isn't overheating. I've changed the coolant, engine and transmission oils and changed the transmission pan filter. Then I noticed this odd little valve on the transmission oil cooler line and it was closed. What is this? I looked in the TM 9-2320-272-20-1 section 5 and the drawings there don't have it as a valve, only an elbow. Is this to bleed air out of the oil line? If I don't bleed it could that cause an air lock that would explain the tranny oil not cooling? I'm kind of at my wits end trying to figure out why it is overheating.

 

[juanprado]

I believe that is the Transmission oil sample port. The military uses lab analysis on its oils to determine maintenance intervals.

There is usually a tube /barb fitting to push a hose on that appears to be missing from the petcock fitting on yours.

 

[Guyfang]

TM 9-2320-272-20-1 This is a maintenance TM. I would look in the -24P. I think Juan is correct, but it never hurts to look in the parts TM's.

 

[purple_duckk]

TM 9-2320-272-20-1 This is a maintenance TM. I would look in the -24P. I think Juan is correct, but it never hurts to look in the parts TM's.

Thanks, I'll give it a look. Doesn't sound like it would be causing my cooking issues.

 

[simp5782]

I had some transmission cooling issues and I thought the transmission oil cooler might be plugged so I removed the coolant lines from the radiator side and it seems to flow coolant from the surge tank out no issues. The radiator seems to be flowing out to it no issues either and the engine isn't overheating. I've changed the coolant, engine and transmission oils and changed the transmission pan filter. Then I noticed this odd little valve on the transmission oil cooler line and it was closed. What is this? I looked in the TM 9-2320-272-20-1 section 5 and the drawings there don't have it as a valve, only an elbow. Is this to bleed air out of the oil line? If I don't bleed it could that cause an air lock that would explain the tranny oil not cooling? I'm kind of at my wits end trying to figure out why it is overheating.

Are you getting your transmission temp from the gauge or an infared gun?

 

[purple_duckk]

Are you getting your transmission temp from the gauge or an infared gun?

Gauge verified with the ir gun

 

[simp5782]

Gauge verified with the ir gun

And what is the temperature?

Does it have 15w40 still in it or ATF?

 

[charlesmann]

That is a sample port valve or i guess it could be used as a bleeder port too. With the tck running, its a squirter

 

[purple_duckk]

And what is the temperature?

Does it have 15w40 still in it or ATF?

I stop and let it cool down if it gets over 250. The one time I let it get much higher than that I had no speed even on flat ground. That was on my ride home after picking it up. I changed the oil, filter, and pan filter since then and haven't let it get that hot again. It had 15w40 in it and that's what I replaced it with.

 

[silverstate55]

Is your fan clutch engaging to let fan come on?

 

[purple_duckk]

Is your fan clutch engaging to let fan come on?

Yes, the radiator fan is coming on and the engine isn't overheating.

 

[silverstate55]

Yes, the radiator fan is coming on and the engine isn't overheating.

What are your IR gun temps on the coolant hoses running to/from heat exchanger? Just trying to verify coolant flow….

 

[purple_duckk]

What are your IR gun temps on the coolant hoses running to/from heat exchanger? Just trying to verify coolant flow….

The coolant hoses are silicone and the coolant sure seems to be able to flow both to the overflow tank and from the radiator. That makes me think it's a flow issue in the oil line from the tranny to the cooler or back from the cooler to the tranny. I saw that valve and hoped it might lead me to an easy solution.

My next step I guess will be to remove the oil lines from the cooler and see if the oil passages flow, then figure out a way to test each line going to the tranny.
I would assume a clogged pan filter would look a lot like this. But since I changed that, I would have to believe the clog would be either in the pickup line or the return line.