It might be time to disconnect the trans cooler.

[svxfiles]

I had to go for a drive yesterday in Christine, my mostly stock 93 SVX.
463 miles in 16°f-28°f weather, highway speeds. 65-79 mph.
This 93 has stock gearing, and a trans cooler, about 18" X 11" X 3/4" in series with the stock, (new) radiator, trans cooler.
I monitored the trans and engine temps during the trip...
The engine stayed at about 189°f for the trip.
Whats a life?
And the trans temp stayed between 136°f and 126°f.
We all know that a 4EAT requires 150°f to fully function, so my lock up TQ was sporadic.
I even installed a cardboard air dam ( about 9" X 12")at the trans cooler to keep the temps up on the return trip, but to no avail.
I just thought I'd mention this because it looks like winter is here.
Tom

[svxistentialist]

Originally Posted by svxfiles

I had to go for a drive yesterday in Christine, my mostly stock 93 SVX.
463 miles in 16°f-28°f weather, highway speeds. 65-79 mph.
This 93 has stock gearing, and a trans cooler, about 18" X 11" X 3/4" in series with the stock, (new) radiator, trans cooler.
I monitored the trans and engine temps during the trip...
The engine stayed at about 189°f for the trip.
Whats a life?
And the trans temp stayed between 136°f and 126°f.
We all know that a 4EAT requires 150°f to fully function, so my lock up TQ was sporadic.
I even installed a cardboard air dam ( about 9" X 12")at the trans cooler to keep the temps up on the return trip, but to no avail.
I just thought I'd mention this because it looks like winter is here.
Tom

Tom, I would not disconnect it, too much trouble.

In theory you could have completely blocked the air from the cooler, and you would have still had the equivalent of "stock" cooling happening at the air/liquid cooler in the corner of the rad, because you are running series connections.

The blocker you put in only closed half the extra cooler. Why not try it with a 100% cardboard barrier? It has to be plenty safe, you still got the original cooler.

Joe

[svxfiles]

Hi Joe.
It is much easier for me to just disconnect/bypass it for the next 3-4 freezing months that to try to insulate/isolate it.
If I only blocked the front of it it would still radiate heat from the other surfaces.
I do not usually have the option of such a leisrurely drive but took the time to see what was happening under the bonnet.

With no lock up converter I still got 24.5mpg+.

[n00b on demand]

That tranny cooler did it's job for me very nicely

[Crazy_pilot]

Originally Posted by svxfiles

With no lock up converter I still got 245mpg+.

Tell me your secret. Now.

[svxfiles]

Originally Posted by n00b on demand

That tranny cooler did it's job for me very nicely

40 days since your last post!
Are you stalking Christine?!


She just got a new rad, a new knock sensor, and soon a new O2 sensor!






You see, She is STILL bleeding me!

[SSSVX]

Originally Posted by Crazy_pilot

Tell me your secret. Now.

even the #1 hybrid can't get that high

maybe the car was towed by a high speed truck with the engine running

[svxistentialist]

Originally Posted by svxfiles

Hi Joe.
It is much easier for me to just disconnect/bypass it for the next 3-4 freezing months that to try to insulate/isolate it.
If I only blocked the front of it it would still radiate heat from the other surfaces.
I do not usually have the option of such a leisrurely drive but took the time to see what was happening under the bonnet.

With no lock up converter I still got 24.5mpg+.

When you put it that way, I would agree.

Here in Ireland it's normally very mild. More like 3-4 nights, perhaps, and never much more than a couple of degrees below freezing, so a temporary botch-up with cardboard and cable ties does the trick here.

Do you think that the engines of manual conversions would run colder and less economically in winter?

They no longer enjoy the bonus of the boost heating from the atf oil in the corner of the rad.

Joe

[dcarrb]

I've noticed that the torque converters on both my cars lock-up at about the same point on my daily drive, which is interesting, since the teal has a mid-sized AUX cooler in series with the radiator cooler, while the silver has none. Ditto really-cold-morning distance to 4th gear (near the 1-mile point). I have receipts for the silver's transmission transplant @ 70,000 miles; wonder if maybe the teal's is a bit more warm-natured because it's original.

No, wait... the salesman said it had been rebuilt.

dcb

[dannmarr]

I don't fully understand. The trans cooler is useful during the warm months but not during the cold months? Do I need to do something? I do live in the Poconos and it does get very cold.

[dcarrb]

Originally Posted by dannmarr

I don't fully understand. The trans cooler is useful during the warm months but not during the cold months?

If the cooler works too well, the ATF won't reach proper operating temperature in cold weather, preventing torque converter lock-up.

dcb

[svxfiles]

Originally Posted by dannmarr

I don't fully understand. The trans cooler is useful during the warm months but not during the cold months? Do I need to do something? I do live in the Poconos and it does get very cold.

If you have a way of measuring your trans temp, and the trans temp goes up to, 150°f, up to 190°f or so, then you do not have to do anything.
However I will disconnect it during the wintwer months, to make sure that my trans temp hits the reccomended 150° f to work properly and fully.

[svxistentialist]

Originally Posted by dannmarr

I don't fully understand. The trans cooler is useful during the warm months but not during the cold months? Do I need to do something? I do live in the Poconos and it does get very cold.

Danmarr, it is a little hard to grasp because the OEM cooler for the ATF, this is down in the left corner of the radiator, part of the radiator. This cooler has two modes of operation, and it would help to think of it as a heat exchanger.

In the morning when the oil is cold, as soon as water is going through the rad the OEM cooler acts as a liquid/liquid heat exchanger [or intercooler], and hot water from the engine helps the oil to quickly heat up from cold to the 150 degrees it needs to properly operate the automatic transmission.

The other mode of operation is called liquid/air intercooling, this is the normal way radiators work. They lose heat from the metal and the liquid to the cold air going through them.

The main reason people put in an extra ATF oil cooler is because the standard one is not good enough to keep the oil cooled sufficiently in hot or difficult conditions. Naturally, as you have added greater cooling capacity, you get the desired result of keeping the tranny oil cool in hot conditions, which prolongs the life of the oil, which prolongs the life of the gearbox.

The potential problem is this higher cooling capability of your new system may keep the transmission oil TOO cool in cold climates for winter use.

Hence Tom's problem above.

Joe

[SVXRide]

OT,
So, if the input line to the cooler long enough to just move over to the stock radiator?
-Bill

[svxfiles]

Originally Posted by SVXRide

OT,
So, if the input line to the cooler long enough to just move over to the stock radiator?
-Bill

Actualy I was going to take the lines from the aux cooler and route them into each other, (to keep out condensation and spiders) and just run one new line
to the factory rad trans cooler.
Temporarily doing without the aux cooler.

I'll take a picture when I can get back to work on Christine.
Tom