6NZ Pyrometer Temp.

Look at your exhaust manifold and the turbine housing on your turbo. If either one has the color of death (bluish black), kind of like when you've overheated a piece of metal with a torch and let it cool, you're hurting your engine. IMO your egt's are too high, and you're shortening the life of your engine.

 

The OR73whatevers for cat 550 have a tendency to run hot and risk blowing quickly at least thats what i kept hearing when i replaced mine so i got an aftermarket one that had the same interals but a thicker housing it run just as cool as my stock for 475 cat did.
After I gave the truck a boost the old stock ran hot around 1150 1200 till it blew so i would get it looked at before you sitting on the side of the road

 

I'd be chasing down the low boost before throwing parts at it.

 

I think he's saying that your higher pyro temps are at least in part as a result of only getting 20lbs boost pressure. You should be over 30, even up to 32 or 34 lbs. You need to find out why you're not getting that, whether it's the fault of the turbo, or a leak somewhere.

 

Too much fuel, not enough air makes high EGTS. What turbo is on it now?

 

Back before intercoolers or some called them aftercoolers, on Cummings we would run them 1200 degs before the turbo and 900 to 1000 after the turbo. Higher elevations could only run about 1/4 throttle (not as much air) or boost anything above those temps could cause scored liners not a gradual thing it could happen quick.

 

Thanks for the update. It had to be leaking.....20 is WAY low.