Ekstra radiator for the aut. transmission???

[DrWin]

Hi guys,

I'm a little confused here. I've been changing coolant hoses today and came across this:
DSC_0196.jpg
DSC_0197.jpg
DSC_0199.jpg
DSC_0200.jpg
DSC_0201.jpg
DSC_0202.jpg
I looks like an extra radiator, stuck to the real one with cable ties, that takes 3 tubes, one disappars into the engine room and the two other attaches to the aut. transmission. Does anyone have an idéa about what is going on here?

My best guess is that I need to remove it and recreate stock cooling for the aut. transmission, b/c this is wierd and uneccesary?

[RamblinDMC]

The original trans cooler was integrated into the passenger side coolant pipe. An external trans cooler is actually a good upgrade, I'd keep it if it isn't leaking.

[DrWin]

Thanks, I'll consider that. I wonder how I'm gonna drain and refill the coolant fluid on this, though... (?)

[Michael]

Thanks, I'll consider that. I wonder how I'm gonna drain and refill the coolant fluid on this, though... (?)

As little coolant that is in the lines, I would just leave it. When you do a trans service you only change about 75% of the fluid anyway, what's a little more? Also you won't have to guess as to how much extra fluid to add.

That looks like a pretty slick cooler setup BTW....very simple. I don't think I have ever seen that although it looks like a somewhat universal design. I put a PJ Grady wrap on my cooler pipe but I doubt it has the same effectiveness as that one.

20200114_220711.jpg

The important thing us autobox owners gotta know is changing the fluid regularly is a given. I change mine every 6k miles. It's no issue to do it every other oil change. Just pull an extra plug, drain the fluid with the oil. Once you do about 2 fluid changes, it would be safe to say all your fluid is all somewhat new.

[Farrar]

Mine is mounted differently (behind the radiator fans). It seems to work just fine, although I think it's leaking.

[David T]

The transmission in the Deloreans doesn't have a problem with overheating. In fact, it is necessary for it to be at a certain operating temperature to have the right qualities of the transmission fluid for friction and lubricity. Unless the car was used in an area where it encountered excessively high ambient temperatures (Arizona, New Mexico, places like that) you really don't need that cooler. I would leave it if it isn't leaking but the downside is the long lines to and from the cooler and the possibility of a burst hose and once you lose the fluid you won't move. Maybe just replace the hoses with some new, fresh ones. As for changing the fluid, it really doesn;t age badly, it wears out based on mileage. As long as it doesn't smell burnt and is not black it should be OK. As a new owner you should replace ALL of the fluids and filters so you know when they were done and exactly what kind of oil is inside. If the stock oil cooler is still attached to the coolant pipe maybe just get some new hoses and hook it back up.

[Ron]

I agree with keeping the cooler.

As for drain and refilling the "coolant fluid"/transmission fluid, like Michael said, fluid-filter service for a lot of vehicles leave the fluid in the torque converter and lines unchanged. One option (with vehicle on jack-stands):
Service the fluid and filter.
Disconnect the 2 lines going to the cooler(s).
Flush the lines, cooler(s), etc., using a quality flush.
Pour new fluid into the transmission's "from cooler"/intake port, using a hose and funnel, as it pumps fluid into a catch pan from its "to cooler"/output port. (Usually 2 gallons. You can repeat -- Just make sure the quantity in and out are always equal.)
Reconnect the 2 cooler lines.
Check for leaks while it comes up to temp then check for proper fluid level. Double check level after a short drive.

[Citizen]

I put a PJ Grady wrap on my cooler pipe but I doubt it has the same effectiveness as that one.

How does that wrap work....is like a mechanical heatsink? If so, I guess it is cooled by passing air flow.

BTW, that's a really clean (cool looking) engine/trans underside you got there.

...

[Michael]

Thanks!

Yes it's just a cooling fin wrap that goes around the cooler pipe. It included a heat transfer mastic to ensure a good contact and it's a cheap and easy to install mod. According to the site, it lowers the trans fluid temp around 15 to 20 degrees. I'll take whatever I can get because that cooler pipe isn't quite my idea of a true cooler.

[David T]

Another neat "upgrade" sold by PJ Grady is a heat wrap you put on the cross/over exhaust pipe that runs over the transmission. Very few cars have an external cooler like you have on the radiator. Yours is the first one I have seen.