180 vs 190 thermostat in a 3.9 - Defender Source
Defender Source  

Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions


Reply
 
Thread Tools
  #1  
Old June 22nd, 2017, 03:42 PM
wcampbel@nas.edu's Avatar
wcampbel@nas.edu
Status: Offline
Bill Campbell
1994 D-90 ST
Member
 
Join Date: Jan 2005
Location: Arlington, VA
Posts: 735
180 vs 190 thermostat in a 3.9

Is there an appreciable difference to running the cooler thermostat in a 1994 d90 with the 3.9? I read on another thread about the gas mileage suffering, but that seemed to be talking about the 160 stat and that was in an 3.5. If so what are we talk about in MPG difference?
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old June 22nd, 2017, 06:26 PM
Davis's Avatar
Davis
Status: Offline
Chris Davis
94 NAS D90 6.2LS
Member
 
Join Date: Nov 2003
Location: Colorado
Posts: 2,623
The ECU is tuned to be optimal at 188 degrees but that said, you can run a cooler thermo but it won't make the engine run cooler---the opening on the 160, 180, 190 are all the same once they are open/warm. So you open a little earlier---there is nothing good there--you are already well within safe temp. You can also run rich by doing that which can clog cats/foul O2. And in summer it won't stay lower anyways and in winter you wont get warm enough for heat so you wouldn't do that anyways. Run the 188---if everything else is working as it should, you are all set.

Whats going on that you would want to?
Reply With Quote
  #3  
Old June 23rd, 2017, 03:13 PM
wcampbel@nas.edu's Avatar
wcampbel@nas.edu
Status: Offline
Bill Campbell
1994 D-90 ST
Member
 
Join Date: Jan 2005
Location: Arlington, VA
Posts: 735
I just had heard about running one but that it would eat gas mileage. Was curious as to why and how much mileage. I am going to flush the radiator and replace some hoses, so I might as well change the termostat while I am in there and didn't know if there were any advantages/disadvantages to going with the 180 vs the 190.
Reply With Quote
Reply

Lower Navigation
Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Tags
90, thermostat

Thread Tools

Posting Rules
You may not post new threads
You may not 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 Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
3.5 to 3.9 install kellymoe Defender Technical Discussions 3 February 6th, 2006 12:24 PM
3.9 to 4.6 1995 D-90 boxerhips Defender Technical Discussions 5 January 25th, 2006 06:20 PM
3.9 parts Mike Hippert For Sale - Parts 2 September 7th, 2005 01:29 PM
How and Why to add an oil thermostat Hans Misc. Chit-Chat 0 February 18th, 2005 02:57 PM
For Sale: 3.9 Complete Joe B For Sale - Parts 1 April 20th, 2004 02:54 PM


All times are GMT -5. The time now is 02:38 PM.


Copyright
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.