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Discussion Starter · #1 ·
Hey guys,

Since it has gotten cold here my 6BT is just running too cold I believe. It will barely get over 100 degrees running around town and only up to around 150 running down the highway. My first thought is a stuck thermostat, but I wanted to see what you guys think. I know I have read about the 4BT's running very cool and not wanting to heat up...6B's the same way???

Thanks,

Chris
 

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Hey guys,

Since it has gotten cold here my 6BT is just running too cold I believe. It will barely get over 100 degrees running around town and only up to around 150 running down the highway. My first thought is a stuck thermostat, but I wanted to see what you guys think. I know I have read about the 4BT's running very cool and not wanting to heat up...6B's the same way???

Thanks,

Chris
Almost all of the direct-injection diesels are like this. The TDI VWs don't warm up just sitting and idling, you have to drive them a little bit. (Block heaters are your BEST friend for having a toasty vehicle in the driveway..)

I'd suspect a thermostat myself. Make sure that you get a replacement that is meant for the Cummins (has the extra little plate on the end to block off the bypass port as the thermostat opens).
 

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I agree. It won't warm up in your driveway but it should get up to temp with about 5 miles of highway driving and stay there even if your back in town. Mine will cool back down at an idle unless I rev it up to 1250 rpm.
 

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The Isuzu trucks actually close the exhaust brake when the engine is cold to get it to temp faster.

Could be a plan if you have an exhaust brake.
 

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A diesel only uses 30% of its cooling capacity when not under load................the best thing ya can do is get in and drive easy....the help of winter cold fronts is amazing too.......I run a temp sensor in the intake horn and it tells alot of stories
 

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Discussion Starter · #7 · (Edited)
Are you going off the stock gauge or actual temp ?

Scott

Yes, I am using the factory sensor with the sender in the block just below the thermostat housing. I have to think it is close to correct because I get no heat from the heater for a long time.

I guess the cold air intake and intercooler in 30 degree weather must just make it run cold??

My main concern is that 150 degrees is just not hot enough. It needs to be closer to 200 to keep oil contaminants and such cooked out as well as getting things up to temp from an internal clearance standpoint. Maybe block a portion of the radiator with cardboard when it is real cold?
 

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you need 190-200 to flash the oil

yes you can cardboard the rad but leave a 4" hole in the center open otherwise the fan will be flexin so much that it will eventually brake a blade off

if you never tow or dont use AC in the winter then pull the fan blade altogether
 

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Discussion Starter · #9 ·
you need 190-200 to flash the oil

yes you can cardboard the rad but leave a 4" hole in the center open otherwise the fan will be flexin so much that it will eventually brake a blade off

if you never tow or dont use AC in the winter then pull the fan blade altogether
Mine has two electric fans that are thermostat controlled. They have not been running at all.
 

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I would replace the stat to to be safe might have somthing stuck in it , they run cool to start with but will wrm up soon after you drive.

Scott
 
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