Engine Operating Temperature Cummins ISL

[fthorwart]

Can anyone tell me what the normal operating temp, should be in Cummins ISL 370 Newmar motorhome.

 

 

[wolfe10]

Fthorwart,

Welcome to the FMCA Forum.

Best advice is to call Cummins with your engine serial number.  They can give you the proper operating temperature.  If you have a side radiator and/or rear radiator with fan controller, temperature will vary between thermostatically controlled temperature and 5-10 degrees higher where the fan kicks to high speed.

Cummins 800 343-7357

 

To locate your engine serial number:

In general, Cummins engine serial numbers consist of eight (8) digits, e.g. 79012323

ISC and ISL: The dataplate is located on the top side of the gear housing.

[manholt]

What temperature are you currently reading and has it changed from previous readings?  What environment are you in now and is it different from your normal areas to travel or live in?  What year and model is your Newmar DP? 

Carl C.

[wildebill308]

16 hours ago, fthorwart said:

Can anyone tell me what the normal operating temp, should be in Cummins ISL 370 Newmar motorhome.

 

 

Welcome to the forum. Brett is right best place to get the facts is Cummins. The temp could vary based on when it was made.

Please add your coach to your signature so you can get better answers in the future.

Bill

[Lenp]

My 370 in a 2002 Winnebago has a 165 degree thermostat and it will run right at 165-170 all day long on flat ground or small hills (even when it is 105 outside).  If I let the transmission do the "thinking" it will run up to 200-210 real quick on a long climb.  I ALWAYS downshift to keep the engine RPM between 1800 & 2000 RPM when in the hills.  You MUST keep air flowing through the engine (not just the radiator) to keep these things cool.  If there isn't enough air flowing the exhaust temperature will climb and subsequently the water temp will also rise.

Lenp

[wolfe10]

And, my 2003 ISL has a 180 degree thermostat and runs very close to that unless a long steep grade where it rises a few degrees until the fan (side radiator) turns on HIGH.

Again, best advice is to call Cummins to determine what is correct for YOUR engine.

[five]

My ISL 400 in a previous coach ran right around 200.

[jleamont]

I hold a steady 180 with a 180 degree thermostat, it will rise on hills to the low 190's towing on a 90 degree day and also in traffic. As soon as I move and the engine RPM's increase it drops back within 1/2 mile.

[manholt]

We still don't know what the OP's is suppose to be!  Only Cummins can tell the OP what it is to his engine....re read Brett.

[kander2015]

 2014 Winnebago Journey 360hp ISL. It runs at 180 on flats and up to 225 on North Carolina mountain roads.

[wayne77590]

Kander2015,

Running WOT (Wide Open Throttle) up grades will cause the engine to run up in temperature. Slow it down, drop down a gear and try and maintain 2000 rpm.  Here is something I do when I see a long or steep grade coming. I'll push down on the accelerator until I reach my cruise control speed, then I take it off of cruise control.  At this point I never move my foot on the throttle I just let the engine do all the work and on occasion I help it by down shifting an extra gear maintaining that 2000 RPMs.   I have run up to 217˚ and as soon as I slow down and down shift to maintain 2000 RPMs the temperature starts dropping.

[ronjudi]

The temperature of my CAT 9.3 is 97degrees C (205F) and my ISL Cummins  was a little lower.   The radiator's job is to get rid of the heat but allow the engine to run at its optimum temperature.   Using a 15 lb radiator cap the big CAT uses two thermostats to make sure if one should stick shut the engine does not overheat.  I am told by the mechanic that these thermostats tend to fail open which means the observer sees coolant temperature abnormally too low.  

On a long hill climb the warmer coolant temperature is desired as it allows greater dissipation of heat. The radiator can pass a lot more BTUs when there is a greater difference between ambient temperature and radiator temperature.   When a young man in the South we were wrongly advised to remove the thermostat so our old automobiles  would run cooler.   That was a mistake as the old leaking non pressurized systems and radiator could not pass enough heat to keep the coolant from boiling.  With age and gaining of wisdom the thermostats were raised in temperature and pressures were increased to 13-15 lbs which allowed the engine to maintain coolant temperatures just below boiling but hot enough for the engine to run at greatest efficiency. Importantly this allows the radiator to pass greater heat amounts on the hottest days.   

Just got back from the CAT dealer and sure enough one of  my thermostats had failed and the engine and radiator were running too cool on a 100 degree day.   After repair with new thermostats and the new red coolant with fancy inhibitors the engine got right up to design temperature and stayed in a rather tight range. Today's car companies take advantage of the modern designs by using higher pressure and temperature systems which TRANSLATES into a smaller and less costly radiator and higher MPG with tighter heat control.  

Check on your exact engine but the non wet sleeve engines run a bit lower design temperatures like 185-190 and the wet sleeve models are very close to or just above 200.  I don't know of any diesel that is designed to run as low as 160 F.    That would make me suspicious of a bad thermostat.       . 

 

[wildebill308]

The overheating is driven when you are trying to accelerate under load even WOT and you can't accelerate or maintain speed. The old term for this is "lugging the engine"  If you can't accelerate  in a gear or maintain speed you need to reduce the load. You can do this by slowing down and or gearing down till you can accelerate or maintain speed. Having good boost and EGT gages will help you know what is going on. Your EGT temps will climb very quickly much quicker than water temperature. Gearing down will also increase your RPM at a given road speed. Be aware what your max RPM is so you don't go over it. 

I have been geting lots of experience last few days on I-15.Today we moved from Brigam City to Moab. Got off I-15 south of Spanish Fork onto 89 then 6 / 191 to I-70 then 191 to Moab. Amazing senarey and you will get a lot of experience driving hills.

Bill

  

 

[manholt]

Bill.  I was on that route last summer, road is fair to good, tight in some places and I was stuck behind a wide load truck all the way to the summit.  Was in 3rd by the top!  Then it started to sleet...in August!  From summit down, it's very good road until you get to flats, just before I-70...yea curves and keeping my rpm's up 1,800 I  My temp stayed below 205 up hill and 190 down.  I also go by my oil and trans temp!  This was before my radiator flush, temp regulator for SilverLeaf replacement and both thermostats replaced. 

[jleamont]

Wildebill308 is right on, your exhaust gas temp will rise very fast if "lugging" the engine. My last truck had an Exhaust temp gauge, I observed the temp climb so rapidly that if you weren't paying attention to the gauge you saw it move so fast out of the corner of your eye and it caught your attention. I found that lugging the diesel engine would create more heat than downshifting the transmission. Once the rpms were up you could see the gauge begin to drop. My last truck was also an automatic, just like my coach it also didn't down shift on its own so I had to manually drop it back so as not to over temp the pistons. My old truck was modified for more HP and torque, my coach is not, that's not to say you couldn't do damage to a stock engine, I prefer to down shift it, fuel is cheap compared to pistons and turbochargers. I drive it like exactly like Wayne mentioned above, works for me. In process now of installing exhaust temp gauge just to make sure I do not do something dumb.

[manholt]

More hp and torque is fine, as long as your trans is geared for it, if not, then it gets into serious money real fast.  I checked on that thought with Cummins and Allison!  No thanks!  I did do it on my 07' Chevy 2500, 4x4 Duromax and it did not cost too much...I sold the truck this morning at 5am local time.  One less insurance payment.  Now, if I can just sell my HD Trike! 

[rsbilledwards]

Jlearmont,

 

Were are you mounting the pyrometer probe, how far behind the turbo/. I have mine to do yet. The guage is in the dash, running the wiring.

 

BillE 

[wildebill308]

The probe should be before the turbo. A good place is where the tubes come together, you will get more accurate results. Best practice is to remove the turbo to catch any shavings so they don't go through the turbo. 

Bill

[jleamont]

Mine is just before the turbo but not at it. If I could photo it I will. I'm concerned the manifold will crack over time. There's not much meat there. I pulled the turbo out while the oil lines were connected blocked off the exhaust intake and started the engine to blow out and shavings. I blocked it with duct tape facing backwards to catch everything. Strange manifold on the ISL two pieces. Hopefully someone aftermarket will make one soon. It wasn't a bad job to do if you like hanging over the engine working. I have to run the wires up front and it's done, not a simple task on a DP.

[jleamont]

Bill, not sure what your factory gauges look like but Autometer will customize a similar product to get a close match. I got almost identical but missed the white needles. 

[wildebill308]

I am running a Banks IQ and economind diesel tuner. I like the desplay as I have a digital and bar graph to show EGT temp. 

Hear is a link to the section on how to install the pyrometer probe. 

http://assets.bankspower.com/manuals/590/96420-Cummins_ClassA-v5-web.pdf

Bill

[jleamont]

Good info Bill. I hope someday Banks begins to make parts for the ISL. Mine is in the same area as the illustration, by manifold design of the ISL its a similar location. Just horrible to access, CAC piping and air intake piping inner twined over on that side.

[rsbilledwards]

Ok got it, before. On my "OLD" Panther the whole thing is a piece of cake to get to. You just lift the bed and all of it is right there, get is and sit down and go to work. Having a helper nice so do not have to get up and over bed wall to acquire the next tool. In this case it looks new no rust corrosion just a big Yellow CAT C 12. Boy do I like this forum...Thank you Bill for the link... I did by the way use the Auto Meter unit Phantom. close

Bill E

[jleamont]

Bill, glad to hear you can get to it easily. I have found the hardest part of mine is the engine sits so low I struggle to reach it, I end up with my face smashed into something and my feet sticking up in the air in the bedroom. Never fails the DW comes in and starts talking to me, then gets mad when I don't answer or carry on a conversation and goes back inside the house.

[rsbilledwards]

There is so much room compared to the Zanzibar some of it could become a cargo bay. I am moving the chassis batteries into it so the 2 additional coach batteries can be on the tray. That pressure washer sat right above and inside the battery compartment so makes sense. It removes a bunch of wiring out of the battery bay and the tray will now close like a bedroom drawer. There is tons of air so they should not have a heat issue and the exhaust is on the other side rearward with the engine between.

 

BillE