Turbo cool down

[gimlimike]

Being new to a DS have been reading a thread about proper turbo cooldown periods and temperatures via a pyrometer ?

I would like to know if the turbo temp is available as a standard feature with a Cummins / Spartan combination somewhere on the instument panel or is it a feature I should add. The coolant temperature guage is apparent but a turbo temp guage is not.

The accepted temperature for cooldown seems to be 350 but is a Cummins ESL 370 HP the same ?

Thanks in advance

[ewlee]

Originally Posted by gimlimike

Being new to a DS have been reading a thread about proper turbo cooldown periods and temperatures via a pyrometer ?

I would like to know if the turbo temp is available as a standard feature with a Cummins / Spartan combination somewhere on the instument panel or is it a feature I should add. The coolant temperature guage is apparent but a turbo temp guage is not.

The accepted temperature for cooldown seems to be 350 but is a Cummins ESL 370 HP the same ?

Thanks in advance

That is a new twist on cool down. Never heard of taking the turbo temp prior to shutting down. According to every class I have been to and every article I have read on motorhomes, just let it idle down, watch your coolant temp, and no problems. According to Mike Cody (Instructor with Freightliner) by the time you coast off the interstate into a truck parking spot you have already started your cool down. Now as far as what I will do, I try to get the coolant temp down to mid to low 180 before I shut down,

[ghaynes754]

Pretty sure that the temp would be on the data bus from the engine. Using a laptop and VMSPC with the appropriate connectors from Silver Leaf Systems you would be able to see the data.

[engine103]

I had a turbocharged Bonanza airplane and it was required to allow the turbo temp to drop below 975F before shut down. But I also have many miles in over the road vehicles and never have worried about turbo cool down. Jim E. OKC

[Unplanned Tourist]

350 is around the minimum exhaust temp you will get at idle. That said, your turbo will be cooling down as soon as you let off the throttle. This is because in a diesel engine there is no throttle valve to restrict air flow into the engine like on a gas engine.
The reason for cooling down before shutdown is to cool the turbo and the oil in it. While running down the road, there is enough oil flow to keep the oil in the turbo from turning to charcoal. Also after cooling down, the oil left in the turbo will be able to keep from burning because it will be well below the flash point.
Hope that clears it up a bit for you.
Happy Glamping.

[Deucenut]

I don't have a gauge that shows the turbo temp or the exhaust temp. What I do is when I come off the interstate where I have been running at 60+mph and into a parking spot, I put the engine on high idle for 3 minutes. And I use my cell phone to time it. If we are only there for a quick stop like letting the dog to go out and pee, I don't shut off the engine. If I come off the interstate and just drive normally through a town for 5 mins or so to the campsite, I don't do a cool down as it will have cooled down already from normal driving.


But if you've been running hard on the highway, a cool down is mandatory or you can literally cook the turbo's oil inside the turbo and have it stick to the walls of the turbo.

[twinboat]

That leads me to believe that none of the engine builders think that precise turbo cool down temperatures is that important.

I worked in diesel powered equipment for 40 years. I only recall 2 sister vehicles with EGT gauges, 1985 DM 800 Mack trucks. They used a tip turbo fan, intercooler filters, that would plug up and cause high EGTs.

We also ran 2, 1000 HP twin turbo Cat V12 engines, that had E stop systems. Processing yard waste caused hundreds of overheat shutdowns and they still lasted over 10,000 hours before we replaced the whole engine due to dusting.

[jarwiebe]

Originally Posted by ghaynes754

Pretty sure that the temp would be on the data bus from the engine. Using a laptop and VMSPC with the appropriate connectors from Silver Leaf Systems you would be able to see the data.

I run with the VMSPC and wonder if anyone could tell my on what PID I would find the turbo temp so that when I bring our coach out of hibernation come spring I could setup a simple gauge to show the turbo temp.

Thanks for any info on this.

[JohnBoyToo]

'Coking' the oil in turbo's WAS a concern 20 to 30 years ago, but it is a thing of the past now... if you do a google search all the warnings are from old references...

Oils are better, turbos are better, and having driven 4 turbo'ed cars and 3 turbo'ed trucks the last 10 years or so, never worry about turbo cool down....

if you think about it, 99 times out of 100 you've already cooled down by the time you get off the interstate and driven a block to the service station or whatever... in fact, that's a better cool down than idling !


but, if you want to do it, go ahead... it's your vehicle, not mine

[Deucenut]

Originally Posted by JohnBoyToo

'Coking' the oil in turbo's WAS a concern 20 to 30 years ago, but it is a thing of the past now... if you do a google search all the warnings are from old references...

Oils are better, turbos are better, and having driven 4 turbo'ed cars and 3 turbo'ed trucks the last 10 years or so, never worry about turbo cool down....

if you think about it, 99 times out of 100 you've already cooled down by the time you get off the interstate and driven a block to the service station or whatever... in fact, that's a better cool down than idling !


but, if you want to do it, go ahead... it's your vehicle, not mine

I agree driving a block or so is sufficient to cool down the turbo. But what about pulling off the interstate into a rest area that is right on the highway? No driving cool down time there.

[spsm]

Shoot your turbo with a laser, before shutting down........... Accurate and cheap also.

[tizzyfit]

Originally Posted by spsm

Shoot your turbo with a laser, before shutting down........... Accurate and cheap also.

Great plan! By the time I lift the bed, then lift the engine compartment hatch, I'm sure the turbo will have spooled down due to ZERO load on the engine. The simple reality, without a load on the engine, the turbo EGT will be down to acceptable limits to shut the engine down within a very short time period. Oh, and don't race the engine just prior to turning the key off.

[Mr_D]

Cummins says that just slowing down going down an off ramp is enough cool down time, unless you just crested something like Eisenhower pass at full throttle.
In most instances a cool down isn't necessary.

[spsm]

Lift the bed and then the hatch. That's enough for a cool down on ourselves. LOL