Lenny Kritz

Replaced the thermostat, when it hits 180 when i turn the heater on it drops down to 140, blows cold, wait 5 min. Jumps back to 180, does the same thing again, freezing my butt off in north dakota need help. I can pull the radiator cap off after running it 8 hrs, theirs no pressure, its look warm.

j_martin

If I had to guess, I'd say you have stone cold outside air going through your heater. But then what would I know. This is the first gen forum. You have a second gen truck.

shorthair

Update the current Cummins # 3928499 thermostat has NO jingle pins.

ofelas

And thats a second gen 63mm thermostat for a P-Pumped 12v; no jiggle pins needed as the 12v second gen stat housing has a fitting which connects to a check valve in the head.

fj45lvr

couple things about this: 1) Isn't there supposed to be an "inner" and "outer" seal? the inner is thinner and goes in ahead of the thermostat followed by the thick outer with the cut edge.

2) inside the block on my engine there is a not much room to enter before the cast surface and it has another hole there....the aftermarket thermostat from NAPA would have to fit inside this inner hole in the block (and it would compress the spring somewhat to do it since the flat ring attached to the spring is too large to fit inside this inner hole. (I noticed when I removed the thermostat housing that the last person to install a thermostat had it "cockeyed" due to not getting it into the inner hole in block straight when tightening and it deformed and broke the thermostat!

I am returning the NAPA thermostat and getting one from a dealer and hopefully it is not as long (my engine is in a 1992 FL60).

tony seran

Check this out:
https://puredieselpower.com/dodge-pr...g-o-rings.html
Is this the right part for my 1995 RAM 3500 dually? This was the first mention of 2 sealing o-rings.

Attached are the items and their numbers that I bought. Couldn't find the other numbers mentioned.


Thanks,
Tony