Ed,
Thanks for your input and response. Funny you mentioned the thermostat. We are changing that when we take the Sunpro gauge out and replace it with the VDO gauge. When I had the water pump and belt replaced I know they didn't replace the thermostat (it wasn't on the bill). Because we blew the water pump on the road, the repair shop (a Cummins dealer) said they only repaired what was needed to get me back on the road. My fault for not remembering to have it replaced when we did the gauge back home. I also want to check the radiator cap to insure it is proper. As previously stated, all these can add up to more normal operating temperatures. I have to say that since replacing the water pump, our Breakaway has run right around 180 degrees. Fact is, sometimes it is running cooler at 160 or so. That may be a result of the trans cooler we installed already or it may be because of a stuck or non-funtioning thermostat.
As far as purging the water system, I hope the shop that did the water pump did that. Nevertheless, the motor has been run for some time now so it should be good now anyway. This is why the temperature gauge is important to me. It was acting erratic before the water pump went and then pegged itself not long after the pump replacement. I may have been very lucky so far and it is important to me to know what temp I'm running at, as I don't want to replace an engine.
We did use a infrared gun to check the new gauge for correctness. That is when it was determined that the gauge read 8-10 degrees cooler than the actual running temperature. Though I could make note of that and leave things alone, I prefer that it is accurate. When traveling down the road, I want to be able to just look at my gauges and react appropriately and not have to concern with making mental adjustments. With everything else I am concentrating on while driving, I don't need any distractions.

Latest update. I spoke with Spartan today. Nice folks! Here is the scoop on the VDO gauge and sending unit....
They do not stock the gauge, which is their part number 0408-NN1 and is the same as the one installed originally. Cost is $26.46 and would take about 2 weeks to get. They do stock the sending unit, which is their part number 0232-GG3-002 and again, is the same for the one installed orginally. The cost on that is $43.23.
While speaking to Todd at Spartan I was able to get this information from him: The contact on the sending unit for the temperature warning light is 230 degrees, +/- 5 degrees. The recommendation from Spartan for the B5.9 Cummins motor is 239 degrees maximum. Normal operating range for my original motor/trans/rear drive train should be 180-210 degrees, which we pretty much have concluded.
With the originally installed sending unit, it means that when the warning light comes on, I need to get the motor cooled down IMMEDIATELY. There is no real time to play if the sending unit contact happens to be working at a +5 degrees, which would then mean a 235 degree temperature. I told him that I could get a VDO 250F gauge (eGauges part #310-105, cost $25.55) that had better graduations in the operating range (180-220) I should be running at and a matching sending unit (eGauges part #323-099, cost $23.64) that would have a lower warning contact temperature rating (217 degrees, +/- 5 degrees) and if it would be advisable to go that way even if I didn't get them from Spartan. He said many people do their own upgrades with after market items that work well for them and this may be one of them.
Now I am just wondering which way to go and if I should stick with what was there originally or try to update it with something I think would be more advantageous. I am almost 95% sure that I am going to change the gauge to the #310-105 so I have a better feel on the temperature I am actually running at. I can get the sending unit that will have the same warning contact rating (eGauges part #323-100, cost $31.50) as the one that was installed originally. I am wondering if the 217 degree warning contact may drive me crazy because my warning light may go on even in normal conditions if the contact were to be operating at the -5 degrees, which then would be around 212 degrees. So on a pretty hot day operating on some hilly roads the warning light is liable to be blinking on and off. But, I guess it's better to put up with that then toast a motor....

quote:

Originally posted by Bruce & Kathleen:
I spoke with Spartan today. Nice folks!

Excellent post - it helps to get good information to work off of.

quote:

Originally posted by Bill N.Y.:
Contact Spartan, ask them what ranges (temp & resistance) this sending unit controls, find out what the idiot light is set for. It might be 225 for all we know... not the 217 to 230 he quoted you.

Part of being a mechanic is researching things.

Exactly what I was saying - you're above what your mechanic did for you - research doesn't cost - it pays...

Now, don't you feel alot better?

BTW: Thanks for updating this thread - hopefully it'll help the next individual!

Thanks Bill.
Maybe you can move the B5.9 Cummins diesel temperature ratings somewhere else on this site so others can find it easy, since this thread is under VDO Temp Gauge? The most important info on that is the 239 degree max temp, as we all know that just about any motor's normal operating range is 180-210.
Also, what is your opinion on which sending unit to purchase? I'm leaning towards the 217 degree warning light contact setting.....

quote:

Originally posted by Bruce & Kathleen:
Also, what is your opinion on which sending unit to purchase? I'm leaning towards the 217 degree warning light contact setting.....

I would go with that one... it'll tend to keep your eye on the dash when it's starting to run a little hot. Lower, in this case, is better.

quote:

Originally posted by Bruce & Kathleen:
Maybe you can move the B5.9 Cummins diesel temperature ratings somewhere else on this site so others can find it easy, since this thread is under VDO Temp Gauge?

I'm not sure what you're saying... this should stay in Tech Talk.

Are you telling me I should change the title of the post to something else? That makes more sense. Go to the very first post and Edit It. The very first post is where the title is located. Edit it there.

Will Do.
I was not sure if this thread would come up if someone was doing a search for engine temps?