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High EGTs at idle

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  #41  
Old 05-21-2009, 06:42 PM
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Originally Posted by relay93
Dave where is the EGT probe installed? Could the probe be installed to deep and resting on the exhaust manifold? Do you know anyone with thermal scanner to see if you have one cylinder that is hotter than the other?
Just some more thoughts and easier to check.

Good Luck.
The probe is installed pre-turbo, in the pre-tapped hole in the ATS manifold. When I put it in, I pushed it all the way to the bottom and pulled it up about 1/2" or so. I have a cheap infrared thermometer that I got at Harbor Freight. Accurate enough, I guess. Where would I check? The exhaust manifold right out of each cylinder?
 
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  #42  
Old 05-21-2009, 06:45 PM
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Originally Posted by daveO
The probe is installed pre-turbo, in the pre-tapped hole in the ATS manifold. When I put it in, I pushed it all the way to the bottom and pulled it up about 1/2" or so. I have a cheap infrared thermometer that I got at Harbor Freight. Accurate enough, I guess. Where would I check? The exhaust manifold right out of each cylinder?
Yep.
 
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  #43  
Old 05-21-2009, 06:50 PM
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Originally Posted by daveO
So, the rocker arms have play back and forth like, towards the front and back of the truck, but they don't move from one side to the other. What type of lift should I be getting at the rocker arm on the pushrod side? Like if I put a dial indicator on it to verify lift? Also, since the lifters are solid, I take it the only way they would go bad is if they are just worn down. Is this the same for the cam lobes as well?? Thanks for all your input so far guys! I appreciate it.
the only way a cam or lifter could get worn like this is if you or someone else has ran the wrong kind of oil in the truck. the rocker play you discribed sounds normal. measure the lift with a feeler guage where the rocker meets the valve stem valve lash for the intake is .010 inches and the exhaust is .020 inches. this must be done with the engine cold.
 
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  #44  
Old 05-21-2009, 07:00 PM
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Yeah, I got the valve lash specs, I was wondering about the total lift of the cam.
 
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  #45  
Old 05-22-2009, 05:58 AM
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Originally Posted by daveO
Yeah, I got the valve lash specs, I was wondering about the total lift of the cam.
lift on the stock cam is .235 intake and .263 exhaust
 
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  #46  
Old 05-22-2009, 08:39 AM
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Ok, thanks. I'm gonna check that today as well as my valve lash again.
 
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  #47  
Old 05-22-2009, 10:31 AM
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Originally Posted by 94 12valve
lift on the stock cam is .235 intake and .263 exhaust
thats not what the valves are supposed to be set at that is the cam lift. the intake valve lash is supposed to be .010" and exhaust is supposed to be at .020 for heat expansion
 
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  #48  
Old 05-22-2009, 01:41 PM
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Originally Posted by 94cummins12v
thats not what the valves are supposed to be set at that is the cam lift. the intake valve lash is supposed to be .010" and exhaust is supposed to be at .020 for heat expansion
Yeah, I know. I was looking for cam lift to check to see if I was getting the right amount of lift.

Checked valve lash today, everything stayed where it was. Still having the same thing happen. Jumps to 200 on startup, slowly rises to just about 300. Shutdown, won't fall below 450.

If one of my intake valves wasn't seating properly, would that cause exhaust gases to be forced into the intake, and into another cylinder?
 
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  #49  
Old 05-22-2009, 02:30 PM
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Originally Posted by 94cummins12v
thats not what the valves are supposed to be set at that is the cam lift. the intake valve lash is supposed to be .010" and exhaust is supposed to be at .020 for heat expansion
he asked for the stock cam lift I already posted the valve lash

---AutoMerged DoublePost---

Originally Posted by daveO
Yeah, I know. I was looking for cam lift to check to see if I was getting the right amount of lift.

Checked valve lash today, everything stayed where it was. Still having the same thing happen. Jumps to 200 on startup, slowly rises to just about 300. Shutdown, won't fall below 450.

If one of my intake valves wasn't seating properly, would that cause exhaust gases to be forced into the intake, and into another cylinder?
I don't think so ... have you shot your manifold with a heat gun where each exhaust port is?
 
Last edited by 94 12valve; 05-22-2009 at 02:30 PM. Reason: Automerged Doublepost
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  #50  
Old 05-22-2009, 03:51 PM
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Originally Posted by 94 12valve
he asked for the stock cam lift I already posted the valve lash

---AutoMerged DoublePost---



I don't think so ... have you shot your manifold with a heat gun where each exhaust port is?
I tired...apparently, the one I have is only good for 240 deg. I'll have to find one that doesn't suck.
 
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