Since I got my truck together and back on the road, I have been keeping an eye on my pyrometer gauge.

The gauge is the one that came with my previous Hypermax turbo system and has exhaust temperature on one side of gauge and boost on other side.

The thermocouple has been replaced and is an Isspro.

The injection pump has had a washer removed and turned up by the Cummins nut that helped me get the engine in the truck.

I haven't had a trailer to the truck, yet; so, I don't know what it will do under a load.

On long, steep grades, I see the pyro rapidly climb to 1300 or thereabouts; and, on a couple of really bad hills, it shot up to a little past 1400.

Cruising at 65, it will hold around 850-900.

When the gauge climbs, it climbs rapidly.

What is maximum safe sustained pyro temp?? short burst temp??

Do the temps I am seeing sound normal for my equipment; or, is my gauge possibly inaccurate??

How can I check my gauge for accuracy??

Thanks.

 

if the pyro probe is pre turbo 1250-1300 post turbo 1050-1100* max..I have run 1100 post turbo for extended time on my w250 and the radiator will get to hot thats when i have to back out of the go pedal. some here would rather run lower EGTs but thats where I run when towing. my .02
If your not sure about the accuracy of the pyro I would get a new one!

 

I agree. the Cummins guru said 1280 preturbo was the limit. Im sure it would go higher for brief periods, but dont push it.

 

1250 is maximum allowed for 100% duty cycle. As in, Cummins says you can run these engines all day at 1250 and not eat them up.


Lots of guys (wannadiesel ) have trucks that daily see their 1600 degree pyrometers getting maxed out. I don't think it's too dangerous if you only do it a few seconds at a time, but you occasionally see the melted pistons and slagged turbos that result from too-high EGT's on dyno or quarter mile runs. But, they're rare.

 

Bear, your temps seem high all around. If the probe is recent, I would tend to trust the gauge. What's your turbo/air filter situation? Exhaust size? Your pump may be tuned too aggressively for towing, as I'm seeing the temps you see when pulling 8-9k. Can you give some more details of your setup and driving style? That would help

 

Exhaust=3" downpipe to a 2-1/2" Y that feeds two 4" stacks. Yes, I know that the Y is the weak link here; but it is only for six inches. When time allows, it goes.

Intake=Large K-N cone fastened directly to the turbo-intake. Space restrictions were reason for going this route.

Probe=New ISSPRO that was put on the old engine less than six months before the swap. It probably has less than 2,000 miles.

Driving Style=Like a constipated old man. I use only the throttle required to maintain speed. None of that red-neck u-joint wrecking stuff here.

The water-temp gauge does not rise when the exhaust rises; in fact, it runs much cooler than the International I took out.

I am not saying that this is the fastest, most powerful, truck around; but, this thing is wicked.

It is the quickest, most responsive vehicle I have ever driven, including many Cummins powered of all generations; and, it weighs 9400 pounds on the quarry scales--naked truck with big sleeper, double frame, steel bed, and 92 gallon fuel.

 

Bearkiller,

Where abouts in kentucky are you?

 

That "Y" is killing you. The cone filter is probably not big enough either. If it was, the fan would be chopping it up.

Your driving style may be partly to blame as well. RPM is your friend. Loading the engine below the rpm where the turbo spools will drive EGT way up. It's a diesel, it has a governor. You can't over-rev it with the skinny pedal. If the temps get high, gear down.

 

Here is an update on the situation.

I used 4" square tube and miter-cut 22-1/2* angles to custom-build a 4" Y connector for my exhaust.

Exhaust now leaves the turbo through the stock 3" down-pipe, then into 4" square tubing, through a 4" square-tube "Y", into 4" square tube right and left, terminating through 4" diameter stacks, and out the top.

I just got all this assembly hung under the truck and don't see any restrictions now.

I will follow with an update as to how this affects my pyro readings as soon as I go somewhere.

 

Sounds good! I assume you're not intercooled? If that's the case, I would get creative with your intake plumbing and try to shove some fresh air at that turbo. You will notice a difference. I just let go of my BHAF in favor of the original setup and have noticed cooler temps all around except at full boogie, which I can live with.