Transmission Temp - JeepForum.com
 1Likes
Reply
 
LinkBack Thread Tools
post #1 of 38 Old 07-17-2019, 01:41 PM Thread Starter
Hempinfool
Registered User
 
Hempinfool's Avatar
1989 YJ Wrangler 
 
Join Date: Jan 2012
Location: Chapel Hill
Posts: 37
Transmission Temp

History: 93 ZJ 5.2 & 46RH installed in 89 YJ
Last fall with the help of our members, fixed all cooling issues with Liberty mechanical fan, Hayden fan clutch, Champion V8 rad. and Flowkooler pump. 180-190į max in this NC heat.

Now, The tranny is hitting 200į in stop and go traffic and I haven't even tried to climb with it yet.
The tranny cooling is still separated from the engine radiator, while I was trying to figure out the issues. The tranny has a Derale 13950 cooler with a 500 CFM fan which turns on at 180į but it is installed in a place that does not benefit from forced air due to space issues. The tranny also has a deep aluminum pan.

I think I could reconnect the tranny to the radiator and keep in the 180į-190į range but isn't that still too hot?
I know that the stock setup lets the engine go into the 200į range and has the tranny connected.

Thoughts?
I do have just enough space for a passive cooler in front of the radiator if needed.

Thanks in advance for any perspective.

Hempinfool is offline  
Sponsored Links
Advertisement
 
post #2 of 38 Old 07-17-2019, 02:55 PM
Mr. Puddles
Member
1996 ZJ 
 
Join Date: Mar 2018
Location: Little Elm
Posts: 483
Garage
What is your source for trans temp?

Sent from my LM-V405 using Tapatalk

Follow the build!

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


2002 Dakota aka Winnie aka Mad Max
1996 Grand Cherokee aka Puddles aka Pikey Life
Quote:
Originally Posted by kg6mov View Post
The 4.0 is dumb old tractor motor, itís too stupid to know itís supposed to die.
Mr. Puddles is offline  
post #3 of 38 Old 07-17-2019, 02:57 PM
wingless
Web Wheeler
 
wingless's Avatar
1994 ZJ 
 
Join Date: Sep 2007
Location: Florida
Posts: 3,070
Is the DeRale 13950 cooler getting good airflow of cool air?

That looks to exceed the OEM cooler Jeep installed for my 46RH transmission.

It would surprise me if the single-internal-pipe radiator cooler does anything other than rapidly stabilize the transmission fluid temperature.

Mine has the DeRale 14210 cooling pan for extra cooling.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
wingless is offline  
 
post #4 of 38 Old 07-17-2019, 04:35 PM Thread Starter
Hempinfool
Registered User
 
Hempinfool's Avatar
1989 YJ Wrangler 
 
Join Date: Jan 2012
Location: Chapel Hill
Posts: 37
Quote:
Originally Posted by Mr. Puddles View Post
What is your source for trans temp?

Sent from my LM-V405 using Tapatalk
I have the sensor inline as it leaves the transmission. The fitting screws directly into the tranny without any line spacing.
Hempinfool is offline  
post #5 of 38 Old 07-17-2019, 04:41 PM Thread Starter
Hempinfool
Registered User
 
Hempinfool's Avatar
1989 YJ Wrangler 
 
Join Date: Jan 2012
Location: Chapel Hill
Posts: 37
Quote:
Originally Posted by wingless View Post
Is the DeRale 13950 cooler getting good airflow of cool air?

That looks to exceed the OEM cooler Jeep installed for my 46RH transmission.

It would surprise me if the single-internal-pipe radiator cooler does anything other than rapidly stabilize the transmission fluid temperature.

Mine has the DeRale 14210 cooling pan for extra cooling.


I believe it is getting air but not forced from like it would if it were facing forward.
As you can see, I have very little room on either side of the radiator.
I had to cut the grill in order to get the V8 conversion radiator to fit.
You can't see it in the picture, but I think I could get a passive cooler in front of the radiator in the top left side.
Just a thin single core which I could connect in series with the other one.
Attached Thumbnails
IMG_0236.jpg   IMG_0237.jpg  
Hempinfool is offline  
post #6 of 38 Old 07-17-2019, 04:46 PM
Mr. Puddles
Member
1996 ZJ 
 
Join Date: Mar 2018
Location: Little Elm
Posts: 483
Garage
Can you reverse the fan flow and add some ducting to help pull cool air instead of blowing hot air off the engine? Or even duct some cooler air to it from under the radiator?

Sent from my LM-V405 using Tapatalk

Follow the build!

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


2002 Dakota aka Winnie aka Mad Max
1996 Grand Cherokee aka Puddles aka Pikey Life
Quote:
Originally Posted by kg6mov View Post
The 4.0 is dumb old tractor motor, itís too stupid to know itís supposed to die.
Mr. Puddles is offline  
post #7 of 38 Old 07-17-2019, 05:30 PM
wingless
Web Wheeler
 
wingless's Avatar
1994 ZJ 
 
Join Date: Sep 2007
Location: Florida
Posts: 3,070
Thanks for the images.

Please confirm that the fan airflow is sucking in wheel well air over the cooler, then dumping that warmed air into the engine compartment.

Another option is to remove / replace the existing fan w/ one that moves LOTS more air.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
wingless is offline  
post #8 of 38 Old 07-17-2019, 05:39 PM
jay-h
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2006
Posts: 5,686
The fluid coming out of the transmission is the hottest point of al--it's just gone through the torque converterl. If you read the trans pan with an infrared gage, I'll bet it's 30-40 F cooler

My toys
'89 Wrangler YJ
'47 CJ2-A

wife's toys
97 Grand Cherokee (ZJ)
87 MB 560SL roadster
jay-h is offline  
post #9 of 38 Old 07-17-2019, 05:49 PM
wingless
Web Wheeler
 
wingless's Avatar
1994 ZJ 
 
Join Date: Sep 2007
Location: Florida
Posts: 3,070
Quote:
Originally Posted by wingless View Post
Thanks for the images.

Please confirm that the fan airflow is sucking in wheel well air over the cooler, then dumping that warmed air into the engine compartment.

Another option is to remove / replace the existing fan w/ one that moves LOTS more air.
Another change that will have a huge impact is to fabricate a wall, so the air doesn't do an "easy" short circuit loop, from outlet back to inlet, with the same air. This should be the first change.

Make it really difficult for warm air from inside the engine compartment to enter the cooler inlet.

Dual fans, one pushing, the other pulling, on either side of the cooler, will increase the heat transfer.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
wingless is offline  
post #10 of 38 Old 07-17-2019, 06:56 PM
wingless
Web Wheeler
 
wingless's Avatar
1994 ZJ 
 
Join Date: Sep 2007
Location: Florida
Posts: 3,070
Quote:
Originally Posted by wingless View Post
Another change that will have a huge impact is to fabricate a wall, so the air doesn't do an "easy" short circuit loop, from outlet back to inlet, with the same air. This should be the first change.

Make it really difficult for warm air from inside the engine compartment to enter the cooler inlet.
That new wall doesnít need to be steel.

It could be made from a thick rubber sheet, for example. Just seal the inlet to outlet path, as much as possible / reasonable.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
wingless is offline  
post #11 of 38 Old 07-17-2019, 07:12 PM
Mr. Puddles
Member
1996 ZJ 
 
Join Date: Mar 2018
Location: Little Elm
Posts: 483
Garage
Quote:
Originally Posted by wingless View Post
That new wall doesnít need to be steel.



It could be made from a thick rubber sheet, for example. Just seal the inlet to outlet path, as much as possible / reasonable.
What about bed lined aluminum? That would give it strength.

Sent from my LM-V405 using Tapatalk

Follow the build!

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


2002 Dakota aka Winnie aka Mad Max
1996 Grand Cherokee aka Puddles aka Pikey Life
Quote:
Originally Posted by kg6mov View Post
The 4.0 is dumb old tractor motor, itís too stupid to know itís supposed to die.
Mr. Puddles is offline  
post #12 of 38 Old 07-17-2019, 07:38 PM
wingless
Web Wheeler
 
wingless's Avatar
1994 ZJ 
 
Join Date: Sep 2007
Location: Florida
Posts: 3,070
Sure, aluminum would work.

The engine radiator and fan have similar problems. The OEM solution includes a fan shroud, to suck air only through the radiator, not the shown possible / likely to bypass that higher-resistance path. The OEM solution has flexible air dams on the radiator sides so vehicle movement air only goes through the radiator, not those lesser resistance paths to the sides. There is also a large side-to-side gasket that seals the air path above the radiator to the hood, also missing on the modified vehicle.








To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
wingless is offline  
post #13 of 38 Old 07-17-2019, 08:47 PM Thread Starter
Hempinfool
Registered User
 
Hempinfool's Avatar
1989 YJ Wrangler 
 
Join Date: Jan 2012
Location: Chapel Hill
Posts: 37
Quote:
Originally Posted by jay-h View Post
The fluid coming out of the transmission is the hottest point of al--it's just gone through the torque converterl. If you read the trans pan with an infrared gage, I'll bet it's 30-40 F cooler
That is a great idea. I have read a few builds with multiple transmission sensors. My pan doesn't have a preexisting bung and I have always been leary of drilling a pan.
What's the worst that can happen? Get a new pan....
Hempinfool is offline  
post #14 of 38 Old 07-17-2019, 08:49 PM Thread Starter
Hempinfool
Registered User
 
Hempinfool's Avatar
1989 YJ Wrangler 
 
Join Date: Jan 2012
Location: Chapel Hill
Posts: 37
Quote:
Originally Posted by wingless View Post
Thanks for the images.

Please confirm that the fan airflow is sucking in wheel well air over the cooler, then dumping that warmed air into the engine compartment.

Another option is to remove / replace the existing fan w/ one that moves LOTS more air.
The air is being pulled from the tire area towards the engine. I do understand about the air just going around the cooler. I have been delaying the idea of making some inner fenders until I get other issues taken care of but it may be that time.
Hempinfool is offline  
post #15 of 38 Old 07-17-2019, 08:58 PM Thread Starter
Hempinfool
Registered User
 
Hempinfool's Avatar
1989 YJ Wrangler 
 
Join Date: Jan 2012
Location: Chapel Hill
Posts: 37
Quote:
Originally Posted by wingless View Post
Sure, aluminum would work.

The engine radiator and fan have similar problems. The OEM solution includes a fan shroud, to suck air only through the radiator, not the shown possible / likely to bypass that higher-resistance path. The OEM solution has flexible air dams on the radiator sides so vehicle movement air only goes through the radiator, not those lesser resistance paths to the sides. There is also a large side-to-side gasket that seals the air path above the radiator to the hood, also missing on the modified vehicle.






When I purchased the vehicle it already had the engine swap complete but with 1/2 ton axles and 35s. We added tons and 41s and lowered which created many issues that I am dealing with now.
The motor was raised and shifted to the right to allow for the suspension to work. As you said, a fan shroud would do wonders for the efficiency of the engine cooling and I need to find something that will work. The Jeep Liberty fan moves so much air that it compensates for the lack of shroud.
Hempinfool is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome