Temperature Hand Question and recent things done to my 1st Gen since purchase

[MWilliams]

Hello to all,
I recently installed a new water pump, thermostat, hoses, fan clutch and radiator. My temp hand doesn't seem to want to get up to the first 1/3 line on the gauge until I drive around 15 miles or so. I can start to fill the heat in the cab much prior to that and if I come to a stop, the temp hand will rise faster. Is this normal for this year of truck or should I check some things out. By the way, the temp outside was 63* when this was occurring.

I also wanted to list some things I've done to the truck in the last few weeks;
Changed trans oil and filter
Replaced fuel heater o-ring & filter
Installed oem radio
Wiper blades
Bottom window felts for passenger and drivers
All new coolant hoses
All new shocks
Radiator and cap
Thermostat
Water pump
Belt Idler pulley
New belt
Fan hub bearing
Fuel sending float unit
Stater

Some things I still need to do shortly;
Adjust valves
Check injector timing
Chang rear end lube

With the exception of regular maintenance items I hope I will be good for some time after completing the last few tasks.
Thanks for letting me share with you.

 

[cerberusiam]

Where did you source the thermostat from? Low HP engine and oversized cooling system, they did not warm up quickly. A hotter thermostat will help that.

 

[RWherley]

To be honest that sounds about right, or at least that is how my truck behaves, when it gets cold mine will even get a little warmer then then normal (still well with in the safe rang ) when first warming up then drop down to normal temperatures.

 

[MWilliams]

Thanks for your replies.
The thermostat is a gates and was purchased from Geno's, as well as most of the other parts.
As mentioned, this just may be normal for a low hp high capacity cooling system truck. Especially since the cooling system is completely new.
Thanks again.

 

[Wayne M.]

So, in doing that job, you drained and refilled the coolant. How much did you put back in? Have you checked the coolant level after a warm up cycle? Ensure there's no air trapped? My 92 always had a steady needle and good fairly quick heat.

 

[DVolk]

If it is not a OEM cummins thermostat change it ,there issues with non oem units

 

[MWilliams]

I did drain all the coolant including the engine due to installing one of those aluminum freeze plug with the o-ring on the passengers side of the block, (there was a rubber one it it when I bought the truck). I put approximately 5 gallons of coolant in and I have checked it several times and it shows full. I did notice today that the temperature hand was between cold and the first mark after driving 55 mph for 20 miles. At this point I ran the truck up to 65-70 mph and noticed the temperature hand was actually dropping. This has got to be a bad thermostat. Oh, I also stuck a thermometer in the radiator and the hottest it got was 120 degrees after idling for several minutes.

 

[Bluebird]

Just COOOOOOL trucks brother. I put 'bout 10-gallons 50/50 coolant when I serviced this summer. Mine, She behaves just about the same. Summer in So. Cal pulling 500-lbs. up grades it will reach the middle line. Start going down the hill, back to normal which is a good 'tick' toward cold side.
First time I learned the "low HP, heavy-duty cooling system" syndrome. My truck can take up to 25-miles to get gauge half way between cold and normal if it's below 68-degrees.

Enjoy your rig. Good job doing all that stuff. CTD, keeps going and going and going. "Keep an eye on the Dodge."
I bought my Cummins 5.9 w/auto
They threw-in the Dodge with the deal.:-laf Godspeed, Patrick.

 

[Wayne M.]

Sounds like you've filled it. Sounds like a lazy stat.

 

[MWilliams]

Well, I went ahead and ordered the below kit that has the gasket, thermostat and some type of template. I will let you guys know the outcome when it arrives. Thanks for all of your replies.[h=1]3802968 | CUMMINS THERMOSTAT - KIT[/h]

 

[DVolk]

I just put one in a engine im about to install in a truck i have ,a OEM Cummins thermostat it has a something that says not a gasket what is it ???

 

[MWilliams]

DVolk,
I'm not sure what the template is or, what to do with it. Maybe I will figure it out when it comes in.
Below is what the kit I ordered contains;

3972071 - Thermostat, Soft Seat, 4B, 6B X 1 EA
3920336 - Template X 1 EA
3923331 - Seal, Thermostat, 4B, 6B X 1 EA

 

[MWilliams]

I just discovered this from the web: [FONT=&quot] the early heads used a smaller thermostat. The template is to grind out the head to the newer thermostat[/FONT]

 

[MWilliams]

That should have read earlier engines used a smaller thermostat housing and the template is used to enlarge the thermostat housing if needed. I guess my auto correct kicked in and changed some stuff on the other post.

 

[DVolk]

Beats me ,why cabt cummins put a slip of paper saying thius ?? Inbthe boix it comes in

 

[EDankievitch]

My 89 would take a while to warm up unless I was towing and working the engine. I also had installed the much larger 1992 Rad. There was an article in the TDR back in the day on how to install it best advise as the stock Rad would rip the mounting flanges off. I had broke two while the truck was under warranty..... Yes our roads here on Long Island, Ny suck......

 

[MWilliams]

Well, I installed the new thermostat and I now have great heat and the correct temperature gauge readings. The truck does get to normal operating temperature in a short distance and will maintain it at any speed. I can see the cycling of the thermostat that ranges just a tad before the first 1/3 mark and a tad after the same mark. I did however have to cut one of the vent tabs on the new thermostat to make it fit. The thermostat would not fit flush at the 6 o'clock point without doing this.
Thanks for all of your help aView attachment 97003View attachment 97004View attachment 97005View attachment 97006View attachment 97007nd comments.#ad