TheSamba.com :: View topic - My attempt at a transaxle cooler (manual trans)

Mon Jul 28, 2014 8:44 am

I haven't really checked out what Weddle offers, but I'd make the comparison before jumping on Jim Patrick's kit. I notice the lack of electric fan, which our vans need.

Mon Jul 28, 2014 8:51 am

dobryan wrote:
Anyone else have any thoughts on this setup?

It looks like the kit uses a radiator with no fan. The Weddle kit uses a radiator With a fan, recommended.

You can see my cooler install here
http://www.thesamba.com/vw/forum/viewtopic.php?p=6734481#6734481

Here are the Weddle parts that AAtransaxle provided for my tranny cooler
http://www.weddleindustries.com/search/node/cooler

My install, which puts the cooler in the spare tire carrier took about 15' of hose and holds 1 quart more than the actual transaxle fill

Mon Jul 28, 2014 9:57 am

They do offer a fan for that cooler.

http://www.patrickmotorsports.com/part/spal-electric-fan-750-inch-low-profile-pusher/

I'll look at your other installs for ideas as well. :D

Mon Jul 28, 2014 10:07 am

dobryan wrote: They do offer a fan for that cooler.

yes, or you can buy the Setrab unit that has an integrated fan that Weddle Sells.

here are pics of all the parts I got from AATrans, including a hand written sketch and general install layout from Daryl, who provided me with all the parts for a turnkey install.
http://s974.photobucket.com/user/jon_slider/library/tranny%20cooler?sort=3&page=1

the temp gauge came from Speedhut

my cooler installation was done at German Motor Werks, by our samba member vwhead. That includes the relay and fuse protected wiring. Hes done more than one, and might be able to help answer questions you may have. Also feel free to PM me if you like.

fwiw, when AAtrans drilled my case for the cooler plumbing they also drilled for a thermoswitch that turns on the pump automatically.

I added, a manually operated switch on my dash, so I can turn on the pump before the thermoswitch triggers. (Or if the thermoswitch fails, like mine, I can turn on the pump manually)

note this install uses rubber hose that push fit the AN-8 fittings, slightly different than Alarics hose setup

Mon Jul 28, 2014 10:51 am

I run the Tilton pump on my race car. I don't know about in a vanagon, but it makes a ton of noise. On the race car, I have the pump wired to a temp switch so that it runs only when the oil is hot.

Mon Jul 28, 2014 11:13 am

A couple comments for someone comparison shopping or designing their system:

The filter Weddle offers appears to be far better than the one in Patrick's kit.

Patrick's cooler comes without fan because Porsches often use air ducting, rather than an electric fan.

I won't even bother with a thermo switch myself. I consider my brain to be far better at determining when to switch on & off. I believe Jon's found that his thermo switch doesn't know when to turn off, and it certainly can't anticipate a hill for you. Temp gauge is obviously a must.

I believe a dash LED is a must in any install.

I hope to test with a few different pumps, to compare volume, noise, ease of mounting, etc. (Nothing immediate) Pump comparisons are something we need to share, as some may be overkill. I'll be experimenting with inexpensive speed controllers, as well. Some of these pumps can overheat.

Mon Jul 28, 2014 11:30 am

For noise issues, using the same philosophy as power steering lines that incorporate a baffle will help keep the Dbs down to a dull roar :wink:

Mon Jul 28, 2014 11:35 am

I purchased a bunch of fancy parts awhile back to build a replacement system for my experimental one.
My first cooling system using all used race parts, Tilton pump, Aeroquip lines, Oberg filter and 911 fluid cooler are working beautifully.

No thermostat installed and a illuminated toggle on the dash.

Couldn't agree more with Paul, we are smarter and anticipated better than any plumbed switch.

Wed Jul 30, 2014 7:41 am

Jon_slider wrote: here are pics of all the parts I got from AATrans, including a hand written sketch and general install layout from Daryl, who provided me with all the parts for a turnkey install.
http://s974.photobucket.com/user/jon_slider/library/tranny%20cooler?sort=3&page=1

Thanks for posting the instructions from Daryl. I have some of his hand drawn instructions, but never had the chance to talk to him about a cooler set up.

Thu Jul 31, 2014 11:03 am

And here is Weddles plumbing and relay wiring instructions
http://www.weddleindustries.com/sites/weddleindustries.com/files/tech-info/CS-INST_0.pdf

Thu Jul 31, 2014 11:27 am

Thanks! :D

Fri Aug 01, 2014 6:34 am

I have not needed a fan so far staying between 130-150 at 62-70 mph on hot days. The rad is in a direct air flow with nothing in the way.
Just checking over this thread and it dawned on me I still have this same trans in and I just drove it to Crater lake this week. This trans seems to be lasting so far.

Fri Aug 01, 2014 7:21 am

So glad to hear that Alaric.
Safe travels.

Fri Aug 01, 2014 8:11 am

Alaric.H wrote: I have not needed a fan... on hot days.... This trans seems to be lasting so far.

what is the temperature of "hot days"
how many miles is "so far"

Congratulations! and thanks for pioneering and sharing your cooler strategy. Much appreciated.

Sat Aug 02, 2014 8:58 pm

Jon_slider wrote: Alaric.H wrote: I have not needed a fan... on hot days.... This trans seems to be lasting so far.

what is the temperature of "hot days"
how many miles is "so far"

Congratulations! and thanks for pioneering and sharing your cooler strategy. Much appreciated. 105-110 deg and about 20-25 thousand miles

Sat Aug 02, 2014 10:34 pm

Alaric.H wrote: I have not needed a fan so far staying between 130-150 at 62-70 mph on hot days... 105-110 deg... and about 20-25 thousand miles

Congrats on keeping your tranny on the road.

tranny at 150F on a 110F ambient day is a difference of just 40F!!! Outstanding!

with my installation and tire size, my tranny goes to 150F at 67mph, when it is 70F outside. a difference of 80F

I suspect my tires are part of the reason my system runs a higher temperature difference than yours, even though you and I have the same motor.

My radiator is different than yours, and it has a fan running, plus my tires are 245x75x16 (iirc you are on 225x75x16)

Im seriously considering dropping to 225x75x16 in hopes of seeing less than an 80 degree difference between my tranny temp and ambient

when I looked at the tranny temps on a group of vans that went to Syncro Solstice, discussed here http://www.thesamba.com/vw/forum/viewtopic.php?p=7255641&highlight=biggest+tires+hottest#7255641
I noticed that regardless of what motor they ran, among 5 vans, the ones with closest to stock tires, ran coolest.

I think tires that are larger put significant loads, and heat, through the transaxle.

One person that has done a lot of temperature testing is Syncro Jael. He sees a tranny temp that is 69F above outside temp, using 215x75x15 tires, and NO tranny cooler.. his motor is a Subaru 2.2:

Syncro Jael wrote:
We had some 96º ambient temps and the tranny ran about 165º at 65 mph.

so I have a hypothesis, that tire size is a very significant factor in tranny temperatures. As you can see from the photo, Syncro Jael has lots of stuff on his roof, but he still runs cooler than I do with nothing on my roof.

Sun Aug 24, 2014 12:21 am

Since this thread has a lot of the heavy hitters looking at the circulation/cooling/temp issues, I wonder if anyone has experience welding on their 094 main case or gear carrier to add bosses for plumbing/sensors?

Specifically, I'm wondering which alloy rod you used and if it is high enough Mag to need to bag it to weld on it?

Plenty enough experience on TIG'ing aluminum but any advice might save me a lot of trouble.

Thanks
Mark

Tue Aug 26, 2014 2:34 am

OK, since there wasn't a flurry of replies on the welding, I shaved a few bits off of the bad gear carrier and touched a match to it. Sure enough, pretty white sparks. To me that means there is quite a high concentration of magnesium and it will require a glove bag to attempt any welding on it. Unless someone chimes in, I will probably pick up some mag filler rod and an abatement glove bag and give it a try on the scrap gear carrier.
Still interested to hear anyone's experience.

Thanks
Mark

Sat Oct 11, 2014 4:23 am

Update: Welding complete, no glove bag needed. After looking around and talking to a few welders, the consensus was: 1) clean area of any shavings or grindings, 2) make sure you have enough shielding gas around the area of the weld, and 3) practice on something small enough you can cover it with sand if you mess up. (a bad gear carrier was the sacrifice)

Got a pound of AZ92 for under $100 and it all went well.

Mark

Fri Jan 23, 2015 2:28 pm

I found this thread while originally looking for info on gearing/rebuilding my 091 for my '78 Bus with a TDI motor. (Thread in sig.)

If you read the thread, you'll see that the transaxle failed toward the end of a road trip in September. 4th went out, followed by third and a tow.

I think that a good percentage of the failure was due to heat (though even before the conversion, 4th was a little noisy so perhaps it was inevitable).

I say this because though I didn't think to try to measure the heat when it was starting to act up, I had been struggling with the engine's heat issues and was basically driving it by the water temperature gauge, and was going as fast as I could while keeping it less than about 220.

The gearing stock, and I had larger tires to lower RPMs a little, and have since seen (in this thread, among other places) that this can likely contribute to or at least exacerbate heat problems.

Now that I need to get the transaxle rebuilt, I'm concerned with not blowing up another one! So cooling seems like it would be a good thing to consider.

The idea of use of a power steering pump intrigues me.

My TDI engine came with a PS pump, but the bus did not. So I eliminated the pump from the engine, though I still have it in the garage.

Is there any reason any of you can think of that reinstalling the PS Pump, and using it for gear oil as described here, wouldn't be a good idea?