Engine runs really cold w/dual Tstat upgrade

[jerry598]

With dual 195 degree Tstats installed, along with the 9 blade fan and HO waterpump, my dually is running really cold in the winter. So cold that most of the time there is not enough heat in the cab to keep it comfy. Of course, this is Idaho and Wyoming winter driving.

I finally got fed up and duck-taped a piece of cardboard over the grill. Nice difference. It still takes a long time to really warm up, but now after about 20 mins. of driving and when its under any kind of a load at least I have plenty of heat in the cab. No overheating whatsoever.

Anybody know a good source of a nice warm bra for my cold beast?

[twaddle]

Hi Jerry,
What temperature is showing on the coolant temperature gage?
If it's warm inside the cab then the engine is not too cool. It may be that the water temperature regulators aren't opening what with the ambiant winter temperatures and the 9 blade fan blowing through the rad?
Try 180 or 185 degree regulators
Good luck and a Happy New Year as well.

Jim

[handcannon]

When you put on the dual t-stat crossover and HO pump did you re-use the bypass nipple in the water pump from the origional pump? If so, it has no restriction built into it.

This can mean you get a lot of flow through the bypass before the t-stats open. I could be wrong, but this seams like the coolant would not be kept in the block long enough to facilitate a faster warmup.

I have the dual stat and HO pump on my 94. I am having no warmup problems, however there are two differences. (1) I put a restrictor nipple (from Heath) into the HO pump when I installed it. It has only about a quarter inch diameter hole through it instead of wide open. (2) We don't get as cold as you. We've been having a "cold snap" the past few days. Down in the 20's at night and up to the low 40's daytime.

This is just a wild guess. Maybe somebody else has more info on this.

Don

[joed]

To answer your ? about cold fronts, Lund makes a sectional plastic one that is pretty slick - allows you to remove pieces as the temperature changes or if you work the truck harder. It is a 6-piece for the Chevy and 3-piece on the GMC.

I got mine from JC Whitney - I seem to recall seeing other styles at Cabelas.

Joe.

[16gaSxS]

To answer your ? about cold fronts, Lund makes a sectional plastic one that is pretty slick - allows you to remove pieces as the temperature changes or if you work the truck harder. It is a 6-piece for the Chevy and 3-piece on the GMC.

I got mine from JC Whitney - I seem to recall seeing other styles at Cabelas.

Joe.

I bought a Lund years ago and works good last long time.

[jerry598]

Thanks for the replies. Never checked the restrictor nipple in the HO pump. Just put the new pump on and let it go at that. Maybe that's the problem. Will probably go for a bra anyway till the weather breaks and it becomes easier to work outside.

[Kennedy]

There is no restrictor in the water pump niple nor should there be. This is the bypass circuit that allows coolant to circulate through the engine and not the radiator.

Not sure where Bill dreamed this one up...