Sprinter engine temperature

[Jay in TX]

I have a 2019 Sprinter on a 2017 chassis with the 3.0 Diesel.

Recently, on a trip to Yellowstone, the engine temperature rose to 250 degrees. We took it to the closest Sprinter service facility (200+ miles away) by driving at night. They found the fan clutch was not engaging properly and replaced it. They also said the thermostat was stuck closed, but did not have it in stock. I found it hard to believe that we were able to drive it 200 miles with the thermostat stuck and did not have time to wait a week for them to ship it in, so I ignored that suggestion and we drove it without any problems for the rest of our trip (18 days). It did reach temps of 220-230 at times in hot weather pulling a jeep and climbing mountains, but never approached 250 as it had before.

My question for my fellow sprinter owners is what temperature does yours run at most of the time? What is the highest temp you have seem in hot weather under heavy loads? I'm used to gas vehicles that stay under 200, but maybe this diesel with DEF is designed to run hotter? Thanks!!

[KanzKran]

I don't actually know for sure what the engine temp has been in mine on a hot day, but I don't remember it being more than 200F on that crude little scale. The manual says 250F is not out of the normal range. Sounds pretty high to me, though.

As to the thermostat, it may be stuck in a partially open position. I've had that happen on outboards. I don't think you'd be driving at highway speeds for long with the thermostat completely closed.

[Winterbagoal]

Originally Posted by Jay in TX

I have a 2019 Sprinter on a 2017 chassis with the 3.0 Diesel.

Recently, on a trip to Yellowstone, the engine temperature rose to 250 degrees. We took it to the closest Sprinter service facility (200+ miles away) by driving at night. They found the fan clutch was not engaging properly and replaced it. They also said the thermostat was stuck closed, but did not have it in stock. I found it hard to believe that we were able to drive it 200 miles with the thermostat stuck and did not have time to wait a week for them to ship it in, so I ignored that suggestion and we drove it without any problems for the rest of our trip (18 days). It did reach temps of 220-230 at times in hot weather pulling a jeep and climbing mountains, but never approached 250 as it had before.

My question for my fellow sprinter owners is what temperature does yours run at most of the time? What is the highest temp you have seem in hot weather under heavy loads? I'm used to gas vehicles that stay under 200, but maybe this diesel with DEF is designed to run hotter? Thanks!!

Do you mean the engine coolant temperature hit 250F? It's the only MB temperature that can be displayed by using the dash display, that I'm aware of.
My fluid temps (per my SGII) are, coolant 197-202F, oil temp 215F, and transmission fluid maybe 165F in 72F ambient temps, under no signififcant load. Throw in 90F+ ambient, and hill climbs, while towing, and they go up more than a bit.
I'm wondering if you caught your van/motorhome doing a DPF regen, while running it in hotter weather? That pushes my oil temps to around 240-250F for the duration, and the coolant and trans fluid climb as well, sometimes to over 212F until the regen ends, and the temps return to pre-regen numbers.
Had you just started out in the morning after some days of lower speed driving, or had you been driving it regularly during your YNP visit at lower speeds than 50mph, or extended idling while looking around the park? I think the speed limit on 89 in YNP is 50mph or lower?
I might buy the partially open thermostat theory. Possible, but then you drove it as normal for the rest of your trip?
I used to see my Chevy Vortec 350 V8 hit some pretty scary temps a few years back, in the same range as what you're seeing in hot weather under load, and it wasn't really considered harmful or dangerous according to the dealer.
If it gets up there and stays, then start to investigate further. And don't just stop and turn it off. The manual says pull over and let the engine idle for a while, to let the water pump and fan do their thing.

[KanzKran]

Originally Posted by Winterbagoal

I used to see my Chevy Vortec 350 V8 hit some pretty scary temps a few years back, in the same range as what you're seeing in hot weather under load, and it wasn't really considered harmful or dangerous according to the dealer.

My Jeep Grand Cherokee with V6 EcoDiesel got up to about 250F once, on a very long upgrade towing a boat trailer using cruise control in hot weather. No alarms or warnings, but I backed off a bit and manually forced it down a gear or two to get engine speed up a bit. Trans temp was right up there, too. Not something I'm used to seeing, that's for sure, but it would seem the manufacturer didn't think it was cause for alarm.

[move on]

Once while towing with my MB 3.0 diesel (same as Sprinter engine) in very hot weather (100 F +) up a long hill my coolant temperature reached 250 F. At that point my engine derated and I could only go 40 mph max stuck in the slow lane with the semis. After passing the summit the engine cooled down and the computer released the engine to normal operation.

Diesels run hotter than gassers because of their higher compression ratios. Up to 250F is normal.

[Jay in TX]

Originally Posted by KanzKran

I don't actually know for sure what the engine temp has been in mine on a hot day, but I don't remember it being more than 200F on that crude little scale. The manual says 250F is not out of the normal range. Sounds pretty high to me, though.

As to the thermostat, it may be stuck in a partially open position. I've had that happen on outboards. I don't think you'd be driving at highway speeds for long with the thermostat completely closed.

The manual sounds like 250 is ok, but at that point the gauge starts flashing red and the display says to pull over and stop the engine.

As for the thermostat, I thought the same thing that there was no way I could have driven this RV all over the country if the thermostat was stuck closed as the tech advised. The dealership was in Midland, Tx and we drove it all the way to Yellowstone and then back to Texas. I do think it could be possible that the thermostat could be stuck partially open?

[Rocky ARV]

We're nearing the end of a over 3 month roadtrip now, over 12,000 miles. The highest coolant temperature observed on the Scan Guage was 228 degrees. This was in the Southwest with ambient temperature about 105 degrees, 5,000 ft altitude. Coolant would back down to about 210 degrees on level roads & 60 mph.

[Jay in TX]

Originally Posted by Rocky ARV

We're nearing the end of a over 3 month roadtrip now, over 12,000 miles. The highest coolant temperature observed on the Scan Guage was 228 degrees. This was in the Southwest with ambient temperature about 105 degrees, 5,000 ft altitude. Coolant would back down to about 210 degrees on level roads & 60 mph.

Your coolant temps sound pretty similar to mine currently.
Thanks for our feedback!

[KanzKran]

Originally Posted by Jay in TX

I do think it could be possible that the thermostat could be stuck partially open?

It certainly could be. When my Honda OB didn't seem to warm up in the driveway like it normally did (using ear muffs for cooling water), no matter how long I ran it under no-load conditions, I pulled the thermostat and it was stuck in about the middle of its range. I put it in boiling water and it didn't move, and it certainly didn't close once cooled.

Obviously, nobody can say for sure what's going on with yours, but I've seen them get stuck (cars included) somewhere between open and closed, so it's possible yours is doing the same thing.

I would probably change it, as it's cheap insurance. I have no idea if it's a DIY project, though, as I'm still new to this van and its systems. But from the picture of the housing, it doesn't look any more involved than any other small thermostat, assuming it's not hard to get to.

https://www.stockwiseauto.com/dorman...waAmLAEALw_wcB

[RonandDeb]

Mine runs about 220 and that's without towing. I could see how towing would increase it and wouldn't think that 250 would be anything to worry about, although that is in the upper range. Your system will warn you if it becomes too hot and you'll have time to cool it down.

If MB found an issue with the stat, I would have it replaced. Certainly can't hurt. Good luck!

[bigb56]

My coolant temps run up to near 230F when climbing is the desert heat and my oil temp can get to 250+ on a long hill. We don't tow but are maxed out on GVWR at 11K. I shut the AC off and slow down when I see the oil temp getting over 240F. On the downhill side the coolant comes down much faster than the oil. I am using Torque Pro on a tablet so it's right in my face.
What do you guys with the Scangauge II see for high oil temps when climbing in the heat?

[Retiree1]

I realize this thread is about 6 months old, but thought I would respond that my Scangauge II has indicated a high of about 265F. This is while towing about 3600 lbs uphill in Utah with outside temperature in the 90's. I have a Winnebago Navion with the 2016 sprinter chassis. Wonder if anyone has any idea what is considered the maximum oil temperature Mercedes recommends for the sprinter?

[bigb56]

Originally Posted by Retiree1

I realize this thread is about 6 months old, but thought I would respond that my Scangauge II has indicated a high of about 265F. This is while towing about 3600 lbs uphill in Utah with outside temperature in the 90's. I have a Winnebago Navion with the 2016 sprinter chassis. Wonder if anyone has any idea what is considered the maximum oil temperature Mercedes recommends for the sprinter?

I don't think it's as much how hot of oil the engine can withstand as it is
how hot the oil can get before breaking down to where it can't do it's job and MB requires synthetic oils which can withstand periodic temps to around 300F without significant degradation. If you tow and regularly your oil gets that hot I would definitely ignore the 20,000 mile OCI and go to at least 10,000 or even 7,500.
Like I stated I start to slow down when mine approaches 250 and my first oil change was at 7.000 miles but the previous owners went with the MB OCI and didn't monitor temps at all, they drove it 56,000 miles so who knows, the engine appears to be OK although wear metals might be high. I sent an oil sample at 6,500 and the aluminum was a bit high so I changed it and went with Motul 5W/30 instead of the 0W/30 Mobil1 that MB used.
PS I also turn the AC off when approaching hills, the earlier you do this seems to help.

[donr103]

Anytime eng 250 degrees for more than 5 or 10mins.. I would change oil.. trans too.. anytime radiator fan does not work.. all my oil gets changed .. but that is me.. I keep everything until I die.. if plan to get rid of it some time.. it's up to you.. dealers don't care and therefore never suggest to have oil changed..
Good luck and keep us posted