Transmission cooler size

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

Brooksie

Guru
Joined
Oct 20, 2007
Messages
1,310
Location
USA
Vessel Name
Island Seeker
Vessel Make
Willard 36 Sedan
I'm beginning to think my Velvet Drive 2:1 may have too small a cooler on it. (2x6 bundle) What size is your cooler?
 
Brooksie
What is transmisson brand and the operating temperature (via an IR gun)?
 
Definitely check fluid temperature. The max temp (as in, warning alarm and change fluid ASAP) is 190* F for a Velvet Drive. If you're well below that when working it hard, then it's got enough cooling.



The coolers on my Velvet Drive 72Cs (sized same as original) are 2x12 bundles, but my transmissions are handling a lot more power and higher RPM than yours, so it's reasonable to expect them to produce more heat.
 
Have you looked inside the cooler tubes?
It’s a favorite spot for debris to lodge in, especially shredded rubber impeller pieces.
 
Ours are about 2x10" with good flow coming out at idle. You should have a temp and pressure installed.
 
Borg Warner Velvet Drive 1.91:1 160 hp, no IR gun.

For many an IR gun is an essential tool. Pick a half dozen spots, shoot them routinely and a steady state will be established. Any variations will provide information as to necessary maintenance.

BTW, my Hurst transmissions read about 60 degrees F above seawater temperature.
 
For many an IR gun is an essential tool. Pick a half dozen spots, shoot them routinely and a steady state will be established. Any variations will provide information as to necessary maintenance.

BTW, my Hurst transmissions read about 60 degrees F above seawater temperature.

Definitely agree with this. Checking temps when underway using a temp gun is easy, quick and can help spot problems before they become big problems. My VD CR2s run at about 140.

Ken
 
YOu can get I.R. thermometers for less than $40. Find out what the temp is.
When was the last time your gear oil cooler was cleaned? If the oil is NOW getting a bit too warm and the last cleaning was when????? then the first thing to consider is a good cleaning. These things are often the first in line between the seacock/strainer and the raw water pump and they can get plugged by deposits and small debris that gets past the strainer.

To boot if that gear oil cooler is clogging that will reduce the entire raw water supply for the engine itself and could lead to engine overheating.
 
I'm beginning to think my Velvet Drive 2:1 may have too small a cooler on it. (2x6 bundle) What size is your cooler?

What would make you think that?

You can get an IR Heat thermometer for $20 on Amazon. Max temp of ATF is 190F. If you get good raw water flow you shouldn't have any problems. The body of the typical cooler is 9". Total length is 12".

Check flow out of exhaust. It should be a lot. Measure temps of transmission. If a lot of flow but high temps then disks might be slipping. You might notice an rpm drop at max rpm. If it's an ancient transmission oil pump could be worn or internal passages filled with gunk.

Start with temp measurements.
 
What would make you think that?

.


I am getting good seawater flow. What made me think it was that after a long trip, 10 hrs running, the transmission began to "drag" (shaft turns in neutral more than normal) plus I think a 6x2" bundle is too small for this application although my Velvet Drive manual gives no guidance.
I will get an IR thermometer
 

Latest posts

Back
Top Bottom