[962500hd]

So I am planning to tow my jeep into the NC mountains next week, which includes some pretty intense long grades (if anyone is familiar with HWY 421 from Wilkesboro towards Boone). As it sits with the combo in my sig, the "turbo master" manual boost controller will allow it to go up near 15psi. I typically baby the throttle when driving around and not really allow it over 10 or 12 for more than a short period.
I have made this same trip without a trailer before and found that I had to back off the throttle and let the truck slow down on some of the grades in order to keep the boost and EGT in what I felt was a good range (under 1000 EGT and @10psi). It is not a matter of power, with the tune it has plenty, it's more a matter of generating too much heat and sustaining high boost for too long.
The question is, if I adjust the controller to max out at say at 10 or 12, would that allow me to give it more fuel with less heat and thus sustain more speed up the grade? I'd like to avoid having to slow down to a crawl up a long grade in order to keep the boost and EGT under control.

FWIW, the truck was set up this way when I got it, I just haven't had much cause to muck with it until now... also it has a newish radiator and water pump, cooling system seems to be in good working order.

 

[Mikey52]

More air and more fuel, is more btu's. Hope your cooling system is up to it.

 

[962500hd]

Sorry, I'm not following, are you saying that dialing back the boost will help or hinder with the heat, or is it going to come out the same regardless? I know a given amount of air requires a given amount of fuel to avoid leaning out, maybe the only difference is how far I can push the pedal?

 

[OkDually]

Sorry, I'm not following, are you saying that dialing back the boost will help or hinder with the heat, or is it going to come out the same regardless? I know a given amount of air requires a given amount of fuel to avoid leaning out, maybe the only difference is how far I can push the pedal?

Dial it down to 10psi and run it. report your differences

 

[Mikey52]

Sorry, I thought you were trying to turn up the boost and the fuel.

 

[962500hd]

Nah, the opposite. Although I'm not sure how the Heath Diesel tunes work. I can tell that it modifies the transmission programming, removes the factory overboost limit, and presumably it must be calling for more fuel under certain conditions in order to make more power. In my brain I reasoned that maybe a little less boost and a little more "throttle" would richen the mixture, resulting in maybe slightly less power and efficiency but also less heat. I just want to get up the mountain and back without blowing something up.
BTW, what are you supposed to call the throttle pedal on a diesel, since it does not actually have a throttle... just the fuel pedal?

 

[Mikey52]

Not sure about your year truck and the programming, but a diesel is not like a gas engine. Running it rich will definitely lower the power and create a lot of smoke.

I would say drop a gear and keep the rpm's up to climb the hills. That will reduce egt's.

 

[Tommygunner]

I reasoned that maybe a little less boost and a little more "throttle" would richen the mixture, resulting in maybe slightly less power and efficiency but also less heat. I just want to get up the mountain and back without blowing something up.

Just so you know. Richening up the fuel mixture in a diesel engine
will cause higher EGT. Not Lower. That is how these people with their black smoke belching trucks burn holes in pistons.
IMO you should play around with adjustment to the turbomaster. Adjust the boost pressure to find the sweet spot for your tune. A a place where you get safe EGT, close to desired power, No black smoke out the pipe under power. You may want to contact Heath diesel (Now diesel site.com) and get some instructions to set the TM to your tune.
Also with mechanical wastegate control and a tune. It is common to control EGT with your Right foot when towing.
You can safely run 1050 EGT in a 6.5. Coolant should not go over 210 on extended pulls.

 

[962500hd]

thanks, good idea to give Heath a call, I may do that today.

 

[OkDually]

BTW, what are you supposed to call the throttle pedal on a diesel, since it does not actually have a throttle... just the fuel pedal?

That is a fly by wire system. All monitored by the ECM via the APPS ( Accelerator Pedal Position Sensor )

 

[okcjetmech]

If your really worried about your egt's get a water meth injection system, that will help a lot.

 

[TheJoggernot]

What turbo are you running ?

 

[Keith_J]

If EGT is over 1150 without black smoke, check charge air temperature. Compressors become heaters when off the efficiency island. Water injection if you cannot intercool.

 

[962500hd]

What turbo are you running ?

Factory original as far as I know.

 

[TheJoggernot]

Factory original as far as I know.

That's a significant part of your problem then. I'm not sure how mechanically inclined you are, but if you're towing heavier, in hilly area and running a tune, it's of my opinion (for whatever that's worth) you should get a larger turbo.

I can almost guarandamntee you're going to have more noticeable power and lower EGTs.

As someone mentioned, check your intake setup and make sure you're sucking cold air. Moving my filter from the turbo to a cold air location has made noticable power gains and reduced egts (especially EGT recovery) to an extent that I would preach to people.

Intercooler and water injection are also fantastic ideas but you might consider upgrading the turbocharger first. I think it'll put a smile on your face.

 

[962500hd]

Thanks, I'll have to look into that as a future project on the truck. Not something I can get done before thursday . I'd also then start worrying about the heads, but I'm not highly motivated to tear it down far enough to stud the heads. I doubt they have ever been removed on this truck.
I'm an experienced mechanic, just not with turbo diesel applications. I built the jeep I'm planning to tow from the ground up. I've already learned a lot in the year I've had the truck, sorting out maintenance and driveability issues, but I have not touched the turbo.
The S&B intake box takes in air over the fender on the turbo side, so I'm sure it's sucking in somewhat warm air. I have Autoenginuity, I'll see if it can read the IAT as suggested above (if there is a factory IAT sensor?)

FWIW I am also not towing extremely heavy. The flat-fender jeep and trailer combined might weigh 4500lbs. I'd like to be able to tow it 3-4 hours though without worrying about the truck. It's what I bought this truck for.

 

[jhornsby3]

When I had our 95 K2500HD, I towed a 8200# fifth wheel. I opened up the intake by running a CAI and had a 5" exhaust from the down pipe back. Towing on slight hills would max out the EGT's quick. I went with a 3GPH water injection from 35mph and 7lbs of boost and it helped a lot. I also had a secondary injection nozzle that put out 7GPH that I could turn on when needed. This was the only way to pull hills with the trailer and keep the EGT's below 900*. Some hills I would be doing 35MPH in second gear and pumping 11GPH of water mist. At 3GPH and pulling, it would hit 1150-1200 and I would hit the switch for the secondary and I could watch the EGT's drop to 900 and stay right there.

I also ran a 185* t stat in winter and a 165* in summer. When I would have the full mist on, the ECT would drop as well. But I ran the green coolant with the anti cavitation additive and Wetter Water purple in the cooling. It makes a huge difference. Pulling the Oregon Coast range, we have hills that can be as little as a half mile to several miles and low to very steep. Coolant usually stayed on the mark as long at the ambient temps were mild.

With that set up there was only one time I couldn't pull a hill safely. 11,000 lbs going up Cabbage Hill. But I see commercial trucks that can't pull that hill.

Your going to see some temps. Best you can do is pull the hill. Run the gears to keep things in check. And plan that 3-4 hours to be a lot longer. And I would leave in the cool of dark when the air temps are lower. Try that Wetter Water. But use the purple meant for diesel engines. Otherwise it can foam up from the harmonics and then your screwed, as it will foam out the coolant. Two bottles for that system.

 

[962500hd]

Thanks for all the feedback and ideas. For now I backed off the boost controller just a little. I'll report back after my trip. I found a different route that avoids the long steep pull up 421. Plenty of smaller hills to deal with though and overall I'm gaining 3000ft or so elevation. The last 20 miles of this trip are on narrow dirt roads winding through the mountains. Should be an adventure!
I'll see how it goes and evaluate further upgrades, as I intend to make this trip or others like it multiple times per year towing the jeep.

 

[cwalker71]

Sorry, I'm not following, are you saying that dialing back the boost will help or hinder with the heat, or is it going to come out the same regardless? I know a given amount of air requires a given amount of fuel to avoid leaning out, maybe the only difference is how far I can push the pedal?

Dialing back the boost will [help] prevent an overboost situation that causes the computer to go into "limp" mode. Mine does it all the time if it goes over 12 PSI for any extended period. I can never drive my truck with the pedal to the floor.

 

[962500hd]

Dialing back the boost will [help] prevent an overboost situation that causes the computer to go into "limp" mode. Mine does it all the time if it goes over 12 PSI for any extended period. I can never drive my truck with the pedal to the floor.

That's one issue I don't have, as my tune eliminates the overboost protection.