Engine/Transmission (1998.5 - 2002) normal temperature drop

[rrab1]

Guy's, the coldest weather since I've owned my y2k is here, five degrees for the high and calling for minus five tonight After getting the water temp up to normal,just below 190 at highway speed I'll have good heat, but when I get in stop and go traffic like today my temp gauge dropped down to the mark half way between 140 and 190 with my radiator blocked off about 50% is this normal for this cummins engine, It only took about ten minutes for this to happen, as alway's thanks in advance, Don Barr

 

[bud kohn]

sounds about normal compaired to mine.

i plug mine in and today i went to work (45 miles of good heat). I left it run as it was -13 degrees for a quick 15 minute meeting. when i came out the temp gauge said 140 or so. when i hookeed up the trailer and towed it smelled like unburned fuel for a couple of minutes. but that seems about normal.



make sure you have blended fuel in your truck as it probably never gets really cold down there as it does further north.

 

[HC]

All three of the diesels I've owned have done this. I think Ford has addressed the problem but with the Cummins you have to put up with it or buy an exhaust brake or Espar.

 

[WDaniels]

Normal, even with an exhaust brake.

WD

 

[HC]

Originally posted by WDaniels

Normal, even with an exhaust brake.

WD

WDaniels,

From your comment, I'm wondering if there is a difference in how your PacBrake and my BD exhaust brake are set up, or, did we interpret the question differently? For example, does your PacBrake stay on even when the engine drops all the way to idle speed, or is it set up only to engage when you are moving?



Even in cold weather (in the teens), if I turn on the exhaust brake at idle, my EGT's rise to nearly 600 degrees (post turbo) and my water temperature is going to rise until the needle is slightly above my normal running temperature. My water temp most definately will not drop with the brake on. Are you saying

that your water temperature still drops under these same conditions?



Or are you saying that when it's "really" cold, like below zero, even the exhaust brake won't keep it warm? Sorry for all the questions; I'm just trying to understand why we have such different answers for the same question.

 

[WDaniels]

HC,

No problem questioning me. I like that, makes me rethink to see if I am correct or sometimes just off plumb. I interpreted the question differently than you. I understood it to mean as he driving he has heat and stays warm. When he slows or stops the heat cools considerably. (inside heat) Even with the PAC break, the heat will drop off. If you sit there for a minute or so the temp gauge will start to drop also. As you start to accelerate again, it will warm up immediately. Mine and I think all the CTD in the dodges up here do that.

But after re-reading it I see my interpretation wasn't wholly correct. But it will still act the same in stop and go traffic.



Are you saying on yours that when you get up to operating temperature(180-195) and you get in slow, stop and go traffic or stop lights that your brake will keep your water up to 180-195 even while idling at a complete stop?

My brake is closed at idle. The micro switch is on the back of the accerlator pedal.

WD

 

[HC]

Originally posted by WDaniels

Are you saying on yours that when you get up to operating temperature(180-195) and you get in slow, stop and go traffic or stop lights that your brake will keep your water up to 180-195 even while idling at a complete stop?

My brake is closed at idle. The micro switch is on the back of the accerlator pedal.

WD

Yes, if I am going slow enough that my foot is completely off the pedal, or stopped and at idle, by turning the exhaust brake "on" my temperature will stay right up at 180 degrees (I have the 180 thermostat so I never hit 190 any more).

It will also warm up to 180 degrees in a few minutes from "cold" by turning on the exhaust brake and idling. Under the same conditions, starting with a cold engine but leaving the exhaust brake off, it doesn't matter how long I idle it, the temperature won't rise much above 140.



The only situation where it might cool would be if I am in very slow traffic where I'm using light throttle which turns off the brake, but not going fast enough to load the engine.



I'm assuming that when you say your brake is "closed" at idle, you mean the butterfly valve is closed, the exhaust is restricted, and is making that "whistling" sound?



If we're saying the same thing, then I'm thinking there would have to be a big difference between the PacBrake and the BD on how much restriction they provide at idle rpms.

 

[WDaniels]

HC,

I finally looked at your location and now I understand why your brake and mine act differently. Right now there is about a 100+ degree difference in the outside temperature. If I were down there my brake would do the same as yours. Yesterday(Friday) when I went to work it was 30 below zero. I drove 35 miles at 65 mph before my thermostat opened up for the first time. During the winter I can be up to driving temperature and shut off the truck and in 10 or 15 minutes the temp gauge will be all the way down to the bottom .

I like your winters there. I spent 3 years at Little Rock AFB at Jacksonville from 77-80. Didn't like the summers tho. To humid.

WD

 

[HC]

Aw, WD, it ain't that bad up there! If you were in Anchorage, we'd be at the same temperature right now; even up in your neck of the woods you'd have to be at -80 right now to be 100 degrees colder than me. (I may even have to wear gloves or a cap today. )



Since the original poster was just north of me in Missouri, an exhaust brake would do the trick for him, too. It was in the teens here recently, and "brake on", my temperatures still rose quickly until the thermostat opened.



Seriously, when you look at the temps seen in Central Alaska, it makes me proud to know that up there, the Cummins engines are still running and starting reliably. I'm guessing stupid people don't always survive the first winter - one mistake or misjudgment at 40 below, and you probably never see Summer again!

 

[2-ND TIME]

cold weather

Lets see if I can remember what was said . For the BD there is minimum back pressure at idle mine was 20 psi and it works well in the cold Canadian north of - 2or 3*C Ha- Ha -Ha I am in southern BC but at home it was -29C the other day. But seriously I run with mud flaps across the rad of various widths depending on the temperature all the way to an 8 " hole in the flap and it works well. mine never goes below about 75*C and there was very little carbon in the down pipe when I changed it out for the exhaust brake so must be doing somthing right in the cold temps?

 

[rrab1]

Hi, I'm the original poster, can you put an exhaust brake on an auto trans? My temps are dropping so fast I'm wondering if my thermostat is getting weak. Thanks Don

 

[WDaniels]

Rrab1,

I know that they made a Pac brake for the 94-98 auto models but don't know if they made them for the 98. 5 and upward.



HC,

Was born and raised in Anchor town. I left there because it became to much like Los Angeles. I drive down to Los Anchorage about once a month. Not even part of Alaska anymore.

WD

 

[2-ND TIME]

exhaust brake

They make an exhaust brake except they don't recommend it for the auto for it is nessecary to add valve lockup switch and extra cooling and maybe one or two others I havn't had to worry about that for I haave a 5 spd and I love it wish that I could have afforded it years ago. It makes warmup faster and going down hills very safe so far havn't locked up the tires on snow ice yet don't look forward to that.