termastat open- should i replace

[jvicars]

i have a 96 3500 w cummins. looks like the termastat is open because the temp never gets above 140-150. truck runs well and i am in fl so its never that cold. i keep reading the truck runs a bit better w an 180 degree termastat and not the 195 standard.

from the looks of it i have to loosen the alternator to replace it which will loose the belt and add more work.

question - do i need to replace it or just let it run as is. thanks.

 

[Mahoney Pursley Ranch]

Should be fine just the way it is in my opinion. The auto makers like the engines to run hot,helps them meet the emissions standards that are imposed upon them by the Feds.

 

[cfpinz]

If it really bugs you that much I'd replace the coolant temp sensor before changing the thermostat. I've got an old 6.9 that probably doesn't have a thermostat, been running cold for years. I keep a piece of cardboard for the radiator behind the seat for when I want heat/defrost.

cfpinz

 

[jvicars]

my opinion as well. i will leave it alone. no need for extra work
thanks.

 

[jvicars]

i bought the truck for 3200. 210k miles, 1 ton, diesel etc. nice truck for the cash.

 

[okbob]

most vehicles now have sensors that affect performance and econimy, they are desiign to operate at different temps and voltages, i would instal the factory reconmend stat, you could end up with a computer trying to compesate for false readings that will never reach thier correct tolereances

 

[c farmer]

Diesels run better the warmer the engine is, I would replace the t-stat. It is not that hard of a job, about 1 hour.

 

[jvicars]

good news is it does not have a computer. its a 96 cummins and i dont i think is all mechanical.

 

[jvicars]

is the belt hard to tighten once? i have to remove the alternative bracket to get to the termastat. i dont have a bunch of auto tools. thanks.

 

[c farmer]

The belt has a spring tensioner that auto adjusts the belt tension. Use either a 3/8 or 1/2 in. ratchet ( I cant remember off hand) to move the tensioner to remove the belt. Disconnent both batterys so you dont throw sparks, take top alt bolt out and you should be able to swing the alt out of the way to take the bracket off. remove t-stat housing to replace t-stat.When refilling with anti-freeze there should be a bleed plug on housing or on the head to bleed air out, if not fill and road test let sit overnight and check level in morning