High Exhaust Temp

[roscoe]

I have a 2003 Mack ch 613 E-7 460, For the last 2 weeks the exhaust temp will

exceed 1150 degrees. I have replaced the fuel filters,air filter, turbo charger

charge air cooler, Anyone have an idea? The manifold pressure is about 30 lbs.

No blink codes are coming up.

[Gambi80]

I have a 2003 Mack ch 613 E-7 460, For the last 2 weeks the exhaust temp will

exceed 1150 degrees. I have replaced the fuel filters,air filter, turbo charger

charge air cooler, Anyone have an idea? The manifold pressure is about 30 lbs.

No blink codes are coming up.

I bet you're losing boost somewhere...either the rubber boots between the turbo, aftercooler and intake manifold...OR the air compressor air intake line that runs from the back of the intake manifold to the compressor. I had that problem with mine, where it goes around the back of the motor it wore a dime sized hole into the pipe...

[roscoe]

When the charge air cooler was replaced the system was pressure checked and held 30 + lbs of pressure with no loss. I will check the compressor connections

again,The engine developes good power but i'm worried about melting it down.

[bullhusk]

Logger, Also check the Pyro & the sensor on engine. I had same problem on one of my Pete's it drove me nuts, so just for hell of it we pulled a pyro. gauge out of another truck and all was normal. In my case it was a bad gauge. BULLHUSK

[roscoe]

I will stick a new pyro sensor in. I've spent so much on this thing a few more bucks can't hurt.Mack has hooked up their laptop to check

for codes or anything else we could think of but came up blank.

[Gambi80]

I will stick a new pyro sensor in. I've spent so much on this thing a few more bucks can't hurt.Mack has hooked up their laptop to check

for codes or anything else we could think of but came up blank.

My old school 427 will consistantly pull 32lbs and has hit 35 on a few occassions (cool mornings). 30 for your 460 sounds lean.

[roscoe]

The 93 460 has a waste gated turbo so when you hit a pre set boost max it opens and by passes. I have thought about blocking the

air line to the control diaphram to see if more boost would reselt in cooler exhaust temp

[roscoe]

OOOps that is an 03 460 not 93

[JerryB]

That sounds low to me too My o4 460 runs around 33-34 in normal running but it sneaks up to 36-37 when I pull it down hard.

[roscoe]

So what sort of exhaust temp do you get from your 460

[Mackpro]

The 93 460 has a waste gated turbo so when you hit a pre set boost max it opens and by passes. I have thought about blocking the

air line to the control diaphram to see if more boost would reselt in cooler exhaust temp

Your 2003 460HP is a CCRS ETECH engine which is a refined ETECH engine. The 460's have the wastegate turbo ( not to be confused with the ASET VGT turbo) , if you try to adjust the linkage and if the boost goes to high it will derate, we already tried this. Mack has some good Service bulletins on the CCRS wastgated turbo. We put alot of diaphragm kit on thoses turbos, its a bitch to get them set right and open when they are supposed to. Another place to look is the intake manifold gaskets, they usually blow out around #1 cylinder, Mack came out with some steer core gaskets to solve that problem.

[roscoe]

Your 2003 460HP is a CCRS ETECH engine which is a refined ETECH engine. The 460's have the wastegate turbo ( not to be confused with the ASET VGT turbo) , if you try to adjust the linkage and if the boost goes to high it will derate, we already tried this. Mack has some good Service bulletins on the CCRS wastgated turbo. We put alot of diaphragm kit on thoses turbos, its a bitch to get them set right and open when they are supposed to. Another place to look is the intake manifold gaskets, they usually blow out around #1 cylinder, Mack came out with some steer core gaskets to solve that problem.

[roscoe]

Mack pressure checked the charge air cooler on the truck which should have detected any loss of air from around the intake.

[Mackpro]

Mack pressure checked the charge air cooler on the truck which should have detected any loss of air from around the intake.

Some techs just seal off both sides of the aftercooler and pressurize it by itself. I leave the aftercooler hose going to the intake manifold on that way you can check the intake manifold and the air compressor intake piping. Of course some of the intake and exhaust valves in the heads will be open and air will go past but with enough air pressure and a squrit bottle of soapy water you can find all kinds of leaks.

[roscoe]

Some techs just seal off both sides of the aftercooler and pressurize it by itself. I leave the aftercooler hose going to the intake manifold on that way you can check the intake manifold and the air compressor intake piping. Of course some of the intake and exhaust valves in the heads will be open and air will go past but with enough air pressure and a squrit bottle of soapy water you can find all kinds of leaks.

[roscoe]

I will contact them in the morning and see if the system was checked correctly I will see if i can find any bad gaskets.

Thanks for the input. There has to be something that isnt right in the system. I will also have them review there bulletins.

and any other info they may have.

[Mackpro]

I will contact them in the morning and see if the system was checked correctly I will see if i can find any bad gaskets.

Thanks for the input. There has to be something that isnt right in the system. I will also have them review there bulletins.

and any other info they may have.

If I was at work I could get you the Service bulletin #'s but I wont be back till Tuesday. Also has the engine ever had the injectors replaced? Some over fueling injectors could be the cause although probably not. Too much fuel or not enough air (boost) usually causes high exhaust temp. If you have any type of fuel heater make sure it is shutoff. Make sure the hole on the inside of the hood is lined up with the air cleaner housing hole and the rubber boot is sealing off the hot air off the engine.

[JerryB]

So what sort of exhaust temp do you get from your 460

At 33-34 boost it runs around 450-500 then at 35-37 boost it runs up to about 700-750. If I lug down it eases up to around 800-900 sometimes but seldom taht high.

[JerryB]

At 33-34 boost it runs around 450-500 then at 35-37 boost it runs up to about 700-750. If I lug down it eases up to around 800-900 sometimes but seldom that high. MackPro will line it out for you. He and fjh have done more to fix my truck with their experienced advice than the local Mack dealership did for me after several shop visits.

I've had coolant pushing problems, blown turbo problems, EUP problems, and charge air problems they talked me through.

[rhasler]

If I was at work I could get you the Service bulletin #'s but I wont be back till Tuesday. Also has the engine ever had the injectors replaced? Some over fueling injectors could be the cause although probably not. Too much fuel or not enough air (boost) usually causes high exhaust temp. If you have any type of fuel heater make sure it is shutoff. Make sure the hole on the inside of the hood is lined up with the air cleaner housing hole and the rubber boot is sealing off the hot air off the engine.

Wastegate Turbochargers — Description, Operation and Troubleshooting SB 214-017

According to VMAC III Service Manual (publication # 8-211) there is a 3300 ohm resistor in the wastegate actuator circuit. An out of whack reading in the signal line will set code 4-5. Since you don't have a fault lamp this probably isn't the problem.

[JerryB]

I found a picture of the pressure tester made by fjh. By capping off both ends of the turbo and airing it up you can test the entire charge air system at once and it's quick

[fjh]

I found a picture of the pressure tester made by fjh. By capping off both ends of the turbo and airing it up you can test the entire charge air system at once and it's quick

We have had problems with the waste gated turbo before the waste gate Maybe stuck open or not sealing properly!As 68 mentioned 33 psi boost is max before derate on those engines!

[roscoe]

Wastegate Turbochargers — Description, Operation and Troubleshooting SB 214-017

According to VMAC III Service Manual (publication # 8-211) there is a 3300 ohm resistor in the wastegate actuator circuit. An out of whack reading in the signal line will set code 4-5. Since you don't have a fault lamp this probably isn't the problem.

[JerryB]

We have had problems with the waste gated turbo before the waste gate Maybe stuck open or not sealing properly!As 68 mentioned 33 psi boost is max before derate on those engines!

Thanks fjh I didn't snap onto what MackPro is saying til you said that. Does the high boost pressure mean I need a new boost relief valve? It seems to have plenty of power and the fuel mileage is good. Maybe my gage is wrong?

Woe is me. I'm a worrier so I better check this out.

[vision386]

So what sort of exhaust temp do you get from your 460

Logger,the exaust temp.in my 01'460 mirrors jerryB's at 33/34 boost approx.450-500 deg. at 35/37 approx. the same,the only time i exceed these parameters is on a hard grade pull, colorado,utah etc. then will get up to 8-900 deg.but this is pretty rare........mark