Turbo timer temp setting

[Kent Kuykendall]

What is a good safe temp to set a turbo timer to shut down engine?



Thanks

 

[Jim W]

If you are stock and have the stock VGT, you do not need one.

I have been deleted and have been since 20K. I never installed a turbo timer to shut down my truck. When I have worked the truck hard like towing my 5er, I will let the truck idle no more than 30 sec. I will then turn the engine off no need for a timer.

The VGT turbo's are now water cooled so they will cool quicker than the previous designed turbos. So in my humble opinion no timer is required.

Jim W.

 

[S.Morris]

two or three minutes should handle most cases unless you just came off the interstate to a roadside stop with a big load and a heavy foot

 

[Kent Kuykendall]

two or three minutes should handle most cases unless you just came off the interstate to a roadside stop with a big load and a heavy foot

I have a probe installed I use to let my 9& cool to at least 300 deg but not sure About the 09. I have it set for 275 I suppose it could be 300 as well not sure.

 

[Jim W]

I have a probe installed I use to let my 9& cool to at least 300 deg but not sure About the 09. I have it set for 275 I suppose it could be 300 as well not sure.

From what I have read in your post your truck is stock, correct?

Well if you are going to wait until the turbo cools down to 275/300F before the timer turns off the motor. This engine will be idling a long long time and you may run out of fuel before it cools to this temperature.



If I remember correctly when my truck was stock, my EGT gage never went below 750F after 5 mins of idling. The 6. 7L engine is designed to run hotter than the older 12V/24V engines. What use to be unacceptable operating temperature for the Turbo are now history. When I was stock I use to see 1300/1450F EGT temps during the regen process, with my shut down temps were in the 800F range.



I now will turn the truck off when my EGT gage reads 600F and this is after 8 hours of towing on the interstate. This is normal temperature that I will turn the engine off at.



A lot of this was debated and discussed back when the first 6. 7L engine was introduced to the market in Jan 07. I believe if you do a search in the 6. 7L engine area you will find all sorts of information that was debated and discuss

Jim W.

 

[Kent Kuykendall]

I am fully deleted now w/smarty Jr. And a quadzilla scoutII monitor. Have not towed with monitor yet but egts seem to cool fast compared to my 98 24v

 

[AH64ID]

There is still a cool down idle chart in the owners manual.

The water cooling on the HE351 will cool the bearing, but it's still important not to shut it down too hot. 400° is the number i have heard for water cooled turbo's. All the 6. 7's I have seen that are deleted cool off just like my 5. 9 does, stock ones may take a little longer if in regen or just post regen.

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[HBarlow]

The ISB6. 7 owner's manuals still contain the same shut down advice that earlier ISB5. 9 HPCR and 24 valve 5. 9s did - 1 to 5 minutes.

Several years ago a TDR member reported that he observed and recorded the shut down time between 5 and 1 minute depending on how his truck was operated just prior to shut down. He compared times to EGTs using a pyro gauge in the exhaust manifold. His observation was that after a hard pull it took 5 minutes to cool down to 400*. I have not taken the time to precisely measure mine but based on seat of the pants cool down time 400* seems right on my truck. I always allow it to cool to 400*.

Now, having said that I am not saying shut down at 600* or 800* will cause early turbo failure. I don't know if it truly matters with a coolant cooled turbo.

 

[AH64ID]

While the turbo bearing is the main reason we cool down prior to shutdown the other reasons are the valves and pistons, all of which don't get the benefit of coolant circulation after shutdown. It's just good practice to allow things to cool prior to shutdown.

If you ever wonder if your cool-down time isn't enough I suggest this trick. Monitor your EGT's after shutdown. If you completely cooled everything they shouldn't rise, or rise much. If they go up 100° or more then the turbo wasn't cooled enough prior to shutdown.

 

[Kent Kuykendall]

Thanks for all the info.