Automatic Transmission Cooler Not Keeping Up

[wesitarz]

I installed my ATF cooler in front of my rad/AC condenser in 03 with my Subaru 2.5 conversion. No problems with the AT.

Last year I replaced my rad with a Nissens and left the AC condenser off since the AC isn't hooked up. I put the ATF cooler in front of the rad (bottom middle) with the same rubber spacers between the rad only and the cooler. I also installed a VDO coolant temp sender in line just off the engine in the line to the rad. I started to see rising coolant temps in stop and go traffic after the engine was at operating temp and usually after the van was stopped for a short time. I replaced the t'stat,water pump,pressure cap. Got the rad fan working by running a second ground (the ground wire was off at the ground tree),then replaced the rad fan switch. I moved the ATF cooler to under the van near my oil cooler (with a scoop) and initially thought the relocation didn't make any difference). Finally, no more rising coolant temps. I figured it was the pressure cap.

A few days ago I moved the ATF cooler back to in front of the rad. I drove out on the hwy for maybe 10km and back and back in stop and go traffic my rad fan comes on high - never did before (coolant temp on VDO gauge is good 180-190) for 30 sec to a minute then shuts off as I drive.

I figure installing the ATF cooler in front of the rad/AC condenser is OK,but without the spacing from the AC condenser the rad coolant can be heated up enough to trigger the rad fan and if your rad fan/rad fan switch is not functioning you may see increasing coolant temps on a VDO/Scan type gauge. It may not be noticeable on the VW needle gauge.
I am going to try doubling up the rubber spacers between my ATF cooler and rad to see if that makes any difference. In the meantime, the rad fan coming on seems to keep things in check.

[wesitarz]

Checked my ATF cooler install today and I have about 1/4 inch clearance from the rad and not touching,which is good according to my Permacool instructions,although this is not a Permacool cooler. Ambient temp is 21 C today which is warm for Victoria. While checking my ATF level after driving in town,the hi speed rad fan cycled on a few times again while the VDO temp gauge showed 180-190. The GW rad fan switch is rated 190-200 I believe.Am I just seeing normal rad fan function maybe with a little heat from the ATF cooler when there is little air flow?

[Wildthings]

[wesitarz]

[BlueNorthWesty]

I just came back from a 1,400 km trip in the mountains. The transmission gauge stayed around 200 F with lower temps on the flatter areas in the 180-190 F range, and occasionally going just over 200 F on steep climbs. By reducing speed on hills I can keep the temps under 200 F.

I may still look into getting a bigger rad-mounted cooler.
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1984 Medium Blue Vanagon Westfalia 2WD w/ rebuilt Auto, Peloquin differential, 3.27 R&P gears, 2002 Subaru 2.5L engine, Girling G60 front brake upgrade, PS, power mirrors

Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=610481&highlight=

[blackglasspirate]

Anyone ever do a pressure test with this setup? With the long, steep, heavy drives I've been doing through the mountains I've suspected that the trans was getting too hot with the smallcar unit mounted in front of the trans and at and angle.

I have the transmission out for other reasons and the mechanic suggested maybe moving it up front. My first question was about pressure, though he didn't seem to think it was a problem.

Just wondering how this setup isn't working for everyone that did it and if you ever hooked up a pressure gauge.
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'87 Vanagon GL Westfalia
IG: @holidayatsee
FB: https://www.facebook.com/holidayatsee

[Wildthings]

I have mine mounted in front of the radiator and it seems to work fine.

[skelly]

I just got the small car cooling unit and plan to install i next couple weeks. However, reading these posts, I am wondering if there would be an issue living in cold climate? I live in Northern Michigan. No mountains, rare 100* days. Don't PLAN to drive much in winter, if at all but days in the 30F range are common. I don't push the van... drive 60mph generally. Rebuilt GW 2.2L engine. Would I run into trouble with the SC unit and ATF being too cold? thanks

[Wildthings]