Filter/cooler for the air-cooled Type 003 Auto Trans?

[MGVWfan]

I've seen the "filter" in my 003 AT, and am not impressed. It's nothing more than rather coarse brass gauze. Also, the torque converter is cooled by air circulated by fins on the TC, but I wonder if our hot SE Texas climate might make some other form of cooling necessary. I looked at the oil flow, and can find no place externally accessible that allows one to remove the oil and return it while being pumped by the internal pump without interfering with the normal flow paths...but what about brazing a second bung to the pan and sucking the oil out with an external electric pump, passing it through a filter and cooler, and returning it via the oil drain bung? I wonder if there are any (relatively cheap) electric pumps that can handle ~220 deg F ATF and pump ~1 GPM against minimal head pressure? Ideas please?

[raygreenwood]

Dang!....what....have you bugged my house? I had this conversation just two weeks ago with someone! .

I think thats a great idea. Two things actually, (1) An electric pump may not put out the volume you want in the end, it may also have long term seal issues with the composition of Dexron lll.

But...how about a small power steering pump from a rabbit or golf? Those are only marginally larger than my fist. They would be easy to bracket into the belt system right over near the left edge of the cooling manifold, and they hae an inline pressure bypass valve so you coul limit the pressure so the pump drags the engine hardly at all. Maybe get about 10-20 psi.....but high circulation. They are bulletproof, last forevever and can be had in the junkyards for about $10. I have been contemplating using this same pump ....modified...as a gear oil circulator on my 004.

I think the fluid to run through the cooler should be pulled right where it dumps back into the pan and the cooled fluid put right into the intake pipe before the filter.

The air Vanes on the torque converter....probably help some...but I have always thought that the windows to let air into the bell-housing are probably out of the air stream. Perhaps a pair of scoops? Ray

[MGVWfan]

Glad to hear I'm not the only one thinking of this. Thanks for the reply Herr Doktor!

Interesting idea, I've seen those little PS pumps (BTW, also available with a poly-V-belt pulley on most late MoPars). The reason I thought electric was that I don't think there's enough space to put a pump over beside the A/C compressor on the left side, and adding a belt will be a challenge, too. I was thinking one of those KE-Jet fuel pumps like the one I got from a Volvo. It appears to put out decent flow at 28 psi, so against less restriction it should produce even better flow. The only question mark is materials compatibility (brushes and synthetic parts in the pump like brush holders), but since there's no rotating seal, I'd bet the pump can handle ATF, but can it handle hot ATF?. I'm thinking of doing a test, pumping ATF constantly for a few days on the pump I have in hand to see if it holds up, maybe heating the ATF somehow for the test. If I kill the pump, I've lost $15, so not a biggie.

BTW, do you mean dump the fluid back into the AT using the dipstick tube somewhere above the O-ring? It'd make getting a good dipstick reading difficult (I have that problem on our '94 Voyager because it has some kind of fluid jet that sprays on the dipstick when it's running). That's why I was thinking of brazing a bung in there.

Where to mount the cooler? How about over the air inlet for the heater (under the left rear fender on wagons, in the rear air duct on sedans)? That way, you can use the heater blower to move air through the cooler, and when the oil cooler t-stat is open in the winter (gotta have a t-stat to keep the oil from getting too cold on those few really cold days down here), the heat adds to cabin heat. Since the heated air dumps overboard through the flap control valves foward of the rear axle carrier (when the flap lever is down), it doesn't heat the inside of the car when heat isn't called for. Just wire a relay to turn the blower on when the engine's running (or use a thermostatic switch and relay). You could do the same thing with an auxiliary engine oil cooler.

Scoops...the air comes in at the top, underneath that metal cover, and exits radially, so a blower ducted into the top shroud would be good.

[vwbill]

Hey, does the auto have a drain plug(17mm hex) like the manual? I wonder if you could use the drain plug as a place to put a external cooler attached either via a hole drilled in the plug or a long treaded plug pipe and attach a hose or fitting to it(or the cooler)and create a natural convection movement(hot to cold) of the oil in the cooler mounted to the side of the case(or the plug) and putting a pickup through the drain plug down into the case to the bottom? Would the cooler need to be lower then the oil level?
What about mounting a cooler where the filler tube mounts by making a manifold at the mounting area? What about some kind of heat sink like they have for a oil filter? Is there a issue with getting the heat out if the outside temp is high and the humidity? Hey what about using the ac evaporator(I think that's the name) and fan that is already there for the ac unit? Mount a cooler there? Is it up front like a T3 at a angle? Bill

[MGVWfan]

The oil pan drain plug is on the rear of the pan, and looks like a bolt (not like the diff fill and drain plugs), so it's too small to have a concentric tube arrangement (but a good idea anyway!). Actually, brazing a bung somewhere else on the pan is easy, so that's not a real problem. It's getting the fluid to flow somehow out to the filter and cooler. As for a heat sink, that might help the cooling a bit, but I think the filter in the AT needs some help...it's sort of the same thing as the oil strainer on a Type 1 engine, so I need a way to pump fluid out of the pan, filter it, cool it, and then return it.

[vwbill]

Sorry to change the topic! Just looked at your pic on the other pic site and looks like a sweet spread of restored engine parts!! Great Job! You're movin along! Bill