[rhfllc]

Last weekend I did a coolant drain to replace the upper and lower hoses, water pump and t-stat for pm. The water pump pulley had a slight wobble so I’m glad I decided to do it. All Cummins parts from Geno’s, the past couple days the temps on the engine and trans have been creeping up higher each day, today when I got home and parked the trans is reading almost 187 at idle, I’ve never seen it over 175 towing at 80 mph. I bled air, ran it to temp after the swap and had good heat after it was up to temp. Just weird, has anybody else had similar, I’ve done a search and not really seeing anything.

 

[SRich12]

Sounds like it most likely still has Air in the system. Takes a bit to get all the air out of the system. Could be a bad thermostat but…… I always only use Cummins stats.


Sent from my iPhone using Tapatalk

 

[rhfllc]

I got a Cummins t-stat and wp from Geno’s so I don’t necessarily suspect those, I’m like you wondering if it’s air but I’ve driven it pretty far the past 5 days and no drop in coolant in the tank.

 

[the man in black]

What are your coolant temps? What were they with the old stat?

 

[krs]

How many times have you topped it up? Each time the engine warms and cools it pushes a little more air out into the reservoir

 

[rhfllc]

What are your coolant temps? What were they with the old stat?

Up to Wednesday they were solidly in the 190’s as usual so i didn’t have any concerns, trans temp was getting into the 170’s which is abnormal. Yesterday I picked my daughter up from school and it idles for maybe 5 mins, when I got back in coolant was 205 and the trans was at 184. By the time I got home it was a couple degrees higher, I sat and idled for a few minutes while I checked the coolant level and it was 208/187. The trans temps is what’s got me thinking something is off.

 

[rhfllc]

How many times have you topped it up? Each time the engine warms and cools it pushes a little more air out into the reservoir

That’s the thing, I refilled after the drain and swaps letting it get to operating temp and cracked the stand pipe banjo bolt and had coolant coming out. I took it for a ride and topped off maybe a quart. That was Saturday. It ran normal Monday, had some higher temps Tuesday than Wednesday/Thursday. I figured it may have had more air but the tank level never dropped any more I haven’t added any coolant since Saturday.

 

[URDiesel]

OAT ?

 

[rhfllc]

OAT ?

Mopar 10 yr. I had been cracking the overflow cap everyday like I said with no change in level. Thursday when I got home I cracked it and a big air bubble came out then I topped it off with maybe a quart. I ran it Friday and Saturday hard and idled a lot and haven’t seen higher than 165 on the trans.

 

[URDiesel]

Sorry! OAT = Outside Air Temp.
Has it chanced over the last few days since you worked on the truck ?

 

[rhfllc]

Sorry! OAT = Outside Air Temp.
Has it chanced over the last few days since you worked on the truck ?

It’s been over a week. Other than a couple days of weird temps I guess it was more air in the system and took a while to get out.