Skip to main content ↑ ↓
Topic: Overheating Cummins 400 ISL (Read 7323 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

Overheating Cummins 400 ISL

Yahoo Message Number: 82565
Background: 2011 travelled approximately 3400 miles, Seattle to Florida to Arizona, no overheating problems; ambient temps 75-85; occasional 90; running temps 185-195
2012: travelled over 4000 miles, Arizona to Missouri, Tennessee, Kentucky, Indiana, Iowa, Nevada back to Arizona; high ambient temps 95-105; running temps 185-205; high temps 210-215 on grades and over 220 (stop to cool off) on every long pull, steep grade over one or two miles.
Remedies: flushed cooling system; pressure tested cooling system; nes radiator cap, new thermostat, new air filter; checked fan operation at Cummins and fan switch working correctly. Cummins could not find any reason, and unit will not overheat unless on hard grade. No coolant loss; radiator cleaned ( side radiator)
A recent thread was discussing adding a manual fan switch; tangentially mentioned a temperature sensor, but didn't mention type of engine.
My question is: could the temperature sensor be giving me this problem? I have gas engine knowledge, but little diesel experience. My fan kicks to high after starting and when checked at Cummins, the wiring is good and the high speed is functioning. Is there a way to test this sensor, if I have one?

Roger Harper
2006 Intrigue
#11990

Cummins 400ISL

Re: Overheating Cummins 400 ISL

Reply #1 –
Yahoo Message Number: 82566
I do not think you have a separate temp Sensor the EMC does that function Bob 06 intrigue 12047 400 ISL

Re: Overheating Cummins 400 ISL

Reply #2 –
Yahoo Message Number: 82567
Roger , no disrespect intended, but 220 is NOT overheating. On my ISX the engine starts to cut back fuel when the temperature hits 240. With less fuel , there is not as much heat and this is built into ECM to reduce the block temperature to protect it. At some higher than 240 temperature, the fuel will be cut back further and eventually send the engine into an idle mode. I suspect that temperature is 260 or more. These are conditions that Cummins sets in the computer to prevent catastrophic failure and even those figures have a CYA factor built in. There are many hundreds of thousands of trucks on the road, and I see very , very few pulled over , pulling the same grades you are talking about. The best thing to do , if you are that concerned about high temperatures is to slow down, and go a gear down so that the engine revs higher to get more cooling water in the motor. Stopping and shutting down the motor is the last thing to do since no heat is being transferred from the engine block when you do that. You can travel ALL day at 220 to 230 and not hurt the engine, since that is within the parameters set out in the engine computer. In fact, you will get a little bit more efficiency at the slightly higher temperatures , since the diesel engine ignites from heat of compression. The 18 wheelers on the road would all be pulled over, if they stopped at engine temps at 220. Just MHO

Ron Baran 09 Magna

Re: Overheating Cummins 400 ISL

Reply #3 –
Yahoo Message Number: 82569
Thanks Ron: I should elaborate that I pulled over but kept the engine running. At 220 my engine hot light comes on the dash, which is why I am concerned. I have tried several grades at slower speeds (45mph) and also have tried several combinations with downshifting; no effect on the red warning light and temps 220+.

Roger Harper
2006 Intrigue
#11990

Re: Overheating Cummins 400 ISL

Reply #4 –
Yahoo Message Number: 82570
Never owned a coach w/an ISX engine, but I can say that I have owned multiple coaches, Cummins ISC 350, ISL 400 and ISM 500s and all of them were programmed to start to derate power around 225 degrees. 220 and up were getting very close to derating(overheating). 190-200 was normal and up to 210 on grades. I did own 1 Cat 525 in a Magna and it did run hotter around 200-210 most of the time, up to 212 or so on grades. These temps were all through the Silverleaf or Aladdin, not a dash gauge.

Brian

Re: Overheating Cummins 400 ISL

Reply #5 –
Yahoo Message Number: 82572
Roger. It would be interesting to know where the " idiot light " on the dash gets it's signal from. On my Silverleaf panel, Silverleaf had the transmission warning come on at 230 , while the engine was set at 240. Many of these settings for alarms are adjustable in the Silverleaf setup, so I changed the trans temp alarm to the same as the engine temp. If you are following temps in your Silverleaf, then that is the accurate reading as Silverleaf takes it's info from the ECM. The engine de-rating modes in the ECM are NOT adjustable and are set from the Cummins factory. If your engine did not de-rate or slow down and go into the protection mode, you have nothing to worry about. You should also note that if you have over the road ( as in engine A/C on ) then the fan on the radiator goes into HIGH automatically. If you had the engine air on, you are also adding to radiator load as the condensor is usually mounted in the coolest air which is before the radiator--that is why they go to high on the fan- automatically. Also note that conditions you described, high ambient temperatures, I would expect to see the coolant temperatures you described-- climbing a grade at 105 will get you 220 If coolant temperatures are 220 at at 80 Ambient or less, then you would be having a radiator problem. Maybe one of the techs following this could say where the dash gets it's "idiot light " signal.

Ron Baran 09 Magna 7025

Re: Overheating Cummins 400 ISL

Reply #6 –
Yahoo Message Number: 82574
Brian For clarification only, is this the warning, of high temp in the Silverleaf or Alladin, or that you have seen that derating number in the printout/computer screen of the ECM settings. As I said , the Silverleaf /Aladdin warnings are adjustable in the Silverleaf/Aladdin, and are not the ECM settings which only a factory service tech could mess with, and I would say you should not touch, even if you could.

Ron Baran 09 Magna 7025

Re: Overheating Cummins 400 ISL

Reply #7 –
Yahoo Message Number: 82575
I have a very different engine (Cat C-15) and after a Silverleaf update (full digital dash etc.), I would occasionally get high temp warnings up long grades, at 220. The silverleaf dash can do yellow 'warnings' and red 'errors', and this was showing as an error, so I'd have to switch dash modes to see what was going on (ie. verify exact digital water temp vs. an analog-type display, plus ensure no other readings looked off). I never saw it go above 224 (this was a very long steep incline in hot weather with dash and OTA AC going).
Note that with my uprated C-15 I'm running 550hp/1850lb.ft with a heavy coach and trailer, so the engine is working pretty hard up those hills (it's usually pinned and usually stays > 50mph, only dropping into the 40's on the steepest of hills), so is going to generate a fair bit of heat J
224 degrees didn't seem very high to me, I know wasn't near enough to cause coolant to boil (even 100% water under cap pressure wouldn't boil at 224), but I thought I'd better verify.
So I called the Cat RV owners's hotline, gave them my VIN etc. They said that the Cat recommendation, at least for my specific engine, is to 'not run above 230 for extended periods', and in response to my question, said that 230 would be a fine point to put the high temp alert at.
I think we (me & silverleaf) compromised and set it at 225, which I've never (yet!) hit, which is nice so I can leave my dash on my preferred page when climbing. However I got so used to switching modes, that I've created a page that I use in hills, showing digital boost pressure, intake, tranny, oil, and water temps, oil pressure, cruise set speed, and of course gear and rpm, all in nice big digits as it can get a little busy esp on twisty hills.
The cruise set speed display is very handy, as when in cruise my Allison 400MH gives me automatic 3-stage Jake Brake control (up to whichever mode manual is set to, I normally leave on 'high'), so will use tranny, or jake modes 1, 2, or 3 as needed. When I'm NOT on cruise control, my tranny will directly engage stage 3, which is often more braking than I need. So I will adjust cruise set speed to get the descent speed I want, with full automatic Jake control, rather than having to constantly manually switch jake mode while descending, which I used to do before I figured this out.

Jim Walsh
2003 Lexa

Re: Overheating Cummins 400 ISL

Reply #8 –
Yahoo Message Number: 82576
Roger: I had a similar experience in July with my 2006 Allure going from Newport Beach to Las Vegas. Coach warmed up to 225 going up Cajon Pass and the Baker Grade - dash light came on, and Silverleaf stuck in "engine coolant temp" message. Freaked out, so I pulled over, let engine idle until it cooled to 200, then started out again, only to pull over and do it over again.
I called Cummins and it was stated that 225 is hot and that at 232 the engine will de-rate causing the coach to slow down to minimize engine damage. I had the radiator and charge air cooler replaced 2 years ago at Premier in Junction City due both leaking (30,000 miles). Had the t-stat replaced earlier this year as "overheating" still occurred. That had no effect on what was happening. Took coach to Colton Truck Repair, replaced fan controller, added material between radiator and CAC to close off cooled air from escaping, wrapped exhaust pipe between engine and muffler, added heat shield to protect chassis wire loom close to muffler.
I also changed the way I drive up grades by slowing to about 55 mph, downshifting to 5th or 4th, as necessary, to hold rpm's to 2,000 or 2,100 and have climbed the Cajon Pass in September with a max temp of 212 degrees - a big change from the Silverleaf climbing to 225 plus and beyond.
I believe that the biggest item was the fan controller that got changed. I now know that if I see the temp climbing like before I can pull the fan controller plug on the bottom of the radiator and the fan will default to "high" and keep things under control.
I'm no expert on Cummins engines, and don't dispute Ron's comments; but end to err on the side of being conservative when it comes to the Allure.

Jim Westling

2006 Allure #11400

Re: Overheating Cummins 400 ISL

Reply #9 –
Yahoo Message Number: 82577
The idiot light corresponded with a red warning on the Silverleaf at 221 degrees. Since both the dash light and Silverleaf confirmed the temp, I pulled over, with the engine running, to cool down. On the pulls between Vegas and Mesa, that meant no fewer than 3 stops for overheating. My dash air was running, so I'm assuming according to you, that the fan must already be on high. Therefore, my thought of a fan switch to turn on earlier in the pull wouldn't be of much help. My trans temp (Silverleaf ) pretty much follows the coolant temp on long pulls, so it was in the 220 range as well. I don't think my trans temp has ever gotten above the 220 and no warning light was showing on the SL at that temp for the tranny. I thought of the AC effect so on one climb, I tried without engine AC and the same result of warning light temp.

Re: Overheating Cummins 400 ISL

Reply #10 –
Yahoo Message Number: 82578
Roger,

The next time you go out pull the fuse for the fan controller. Now the fan should be running at full speed all the time. I have a 370 ISL which is the same block as the 400. With the fan on all the time my coach will run at a constant 178 degrees which is the opening point for the thermostat. If the fan tries to cool it below that the thermostat will close and open controlling the temp. At one time I had a faulty thermostat and with full fan I sometimes would see engine temps around 140. The thermostat was stuck open. One thing is to make sure that your thermostat is ok.
You can easily hear the fan when it goes to full speed specially if you have the driver side window open. There is a big time increase in growl coming from the engine area. In fact you can also hear it pushing up the idle and pull the fuse and then put it back. On my coach I can easily hear it when it switch my dash switch on and off.
On the occasion that my coach overheats the engine temp takes right off marching up very quickly. It is obvious but as soon as I force the fan to high it immediately heads down in only a few seconds. Believe me there is more than enough fan for engine output.
I am not trying to speak to all coaches but on my 2004 Allure turning on the AC does not force the fan to high speed. There is a feed from the AC to the fan controller but it is a switch activated by high compressor head pressure not simply turning on the AC.

Don Seager

2004 Allure 31046

The idiot light corresponded with a red warning on the Silverleaf at 221 degrees. Since both the dash light and Silverleaf confirmed the temp, I pulled over, with the engine running, to cool down. On the pulls between Vegas and Mesa, that meant no fewer than 3 stops for overheating. My dash air was running, so I'm assuming according to you, that the fan must already be on high. Therefore, my thought of a fan switch to turn on earlier in the pull wouldn't be of much help. My trans temp (Silverleaf ) pretty much follows the coolant temp on long pulls, so it was in the 220 range as well. I don't think my trans temp has ever gotten above the 220 and no warning light was showing on the SL at that temp for the tranny. I thought of the AC effect so on one climb, I tried without engine AC and the same result of warning light temp.

Re: Overheating Cummins 400 ISL

Reply #11 –
Yahoo Message Number: 82580
Roger, Here is the procedure for testing you "coolant temp sensor" and "air temp sensor".

1. Crawl under coach and locate your Sauer Dan Foss "Fan Controller" it should be mounted near the fan motor and you'll see a 2 pin power plug/connector and a 6 pin plug/connector.

2. Keep Ignition OFF

3. Disconnect the 6 Pin Connector and you want the engine side of the connector not the side that goes into the controller. The engine side of connector will have small alpha letter A thru F.

4. Take your multi-meter set it on OHMS.

5. Place you Multi-Meter probes in C & D "Coolant Temp Sensor" and record OHMS, now place probes in E & F "Air Temp Sensor" record OHMS
6. With a cold engine, i.e. in the morning both should read 1.2K to 3.0K.

I will send you an off-line e-mail if you'll reply I send you a detailed ambient temperature chart, example at coolant and air temperature of 80 degrees the OHM reading would be right at 2.0K.
These sensors are manufacutred by Airpax/Sensata the Coolant Sensor is Pt.#1090-173 the Air Temp is Pt.#1090-174 both Colton Truck in Calif. and 909-825-4080 and Specialty Logisics 541-515-6651 stock these.

Thanks, Mike 03 Allure 1st Ave. #30898 ISL 370 chipped to 400

Re: Overheating Cummins 400 ISL

Reply #12 –
Yahoo Message Number: 82581
Ron,

Your cooling fan may go to high full time whenever the chassis A/C is turned on but mine does not and I don't think yours should either.
Most of the fan controllers have input from three sources. Those are coolant temperature, charge air temperature and chassis A/C pressure. Take a look at the receiver/dryer in the high pressure side of your air conditioning system. You'll see(I think) three wires coming from a trinary switch in the component. That is input to the Sauer-Danfoss Fan Drive Controller Assembly.
Your '09 with the ISX might be different from the '04 Allure ISL I used to own or the '03 Magna with the C-12 I currently have. But, I don't know why it would be.

George in Birmingham
'03 Magna 6298
George in Birmingham
2003 Magna 6298

Re: Overheating Cummins 400 ISL

Reply #13 –
Yahoo Message Number: 82584
I too have "pulled the plug" on the fan controller to allow the fan to run continuously on high. I've also removed the billboard flap. We pull the van at 8K pounds too. Engine temps run in and around 202F - 210F as reported by the Silverleaf. When I had my radiator replaced the space between the radiator and CAC wasn't sealed properly. For a $6K repair I guess you can't expect all the details to be handled properly. Anyway if this interface between CAC and radiator is leaking it robs air flow from going through the radiator, oil cooler and condenser. Make sure things are tight. I used pipe insulation squeezed into the slot to effect a seal. It's an after through band aid given it wasn't done when the assembly was out in the open. But it worked. Photo here shows poor seal on OEM unit: http://muniac.smugmug.com/Maintenance/Radiator-Repair/i-n4kKWC2/0/M/IMG2284-M.jpg
I think having a constant flow of air through the engine compartment is also a good idea to keep things as cool as possible. (Doesn't change engine/transmission temps.) Keep in mind the transmission runs about 30F hotter than the engine coolant and this adds heat of its own. That being through the transmission oil cooler mounted inside the leading radiator tank. On tough climbs I shift the transmission into whatever gear keeps me around 800 foot-pounds of torque and at around 1500 RPM. Whatever road speed this is, so be it. Sometimes it's 10 MPH. This is ultra conservative but has avoided excessive engine and transmission temperatures. The toughest climb we've done over the past three seasons is on route 80 out of Salt Lake City up over Parleys Summit. It's about a 3000 foot climb in 15 miles. Trucks lay down all over this ascent. The grade isn't linear meaning the last 2 miles are the steepest. Just my hat thrown into the arena of knowledge for what it's worth.

At 12:18 PM 9/23/2012, you wrote:

Re: Overheating Cummins 400 ISL

Reply #14 –
Yahoo Message Number: 82605
Mike, can you recommend a Multi-Meter to use on our 2003 Allure 30951? This is our first MH, and I have so many questions and really no one to answer them. So, do you mind if I pick your brain for awhile? You mentioned that you changed the chip on your 370 to a 400. What changes did you notice on your engine? Cost? Did you do it yourself? How do I set my Gen to come start if my batteries drop to 50% of their capacity? Do you leave your inverter on when parked and not using the coach? I live in traverse City Michigan. It's starting to get cool at night and we're not going to be leaving for Fla until second week of Nov. The settings for my furnace are electric and diesel. I'm plugged into our house for the batt charger. Should I use the electric system? I think I can only use one furnace at a time, or can I use both systems? Mike I think that's about all the questions I have for now. Thanks for your help. John 03Allure 30951

Re: Overheating Cummins 400 ISL

Reply #15 –
Yahoo Message Number: 82610
Ken Retired Cat tech, I agree that 220 is loaded running temp. Cat on newer on the road Diesels made them run hotter due to Emissions! I always used a good analog gauge and warning is not a shutdown! I as now an Owner of a Cummins older 330 never see my themps above 190 but this is an older 8.3 CAPS! Keep us posted if Issue is resolved. Ken 99 Allure 30356.

Re: Overheating Cummins 400 ISL

Reply #16 –
Yahoo Message Number: 82620
All

It really helps in these kind of discussions to know what engine you are talking about. I was getting high temp errors on my C-9 400 when climbing steep grades such as Baker Grade until the CAT guys said to keep the engine in the peak torque range whatever speed that is. The peak torque is around 1100-1200 for the C-9 as I remember. Also, when my fan controller went, pulling over and idling had no effect on reducing temps but pulling the plug did cool the motor. I run 200 to 206 when climbing Baker.

Dan 2006 Allure 31348 C-9

Re: Overheating Cummins 400 ISL

Reply #17 –
Yahoo Message Number: 82623
Well to show my lack of knowledge on all this.
Where is this plug or switch exactly located? Does a person need to climb under the coach to access it? On one trip from Baker to Pahrump (Calif to Nev) my temp did get into the mid 220's. but cooled down after the grade. So, I should get some knowledge on how to quick fix problems. Thanks,
Dave

07 Country Coach Allure 430 #31495 12 Jeep GC Toad Mountains of So Cal
Dave & Jodi
2007 CC Allure 40’ Tag #31495
2012 Jeep GC
Big Bear Lake, Ca & Henderson, Nev

Re: Overheating Cummins 400 ISL

Reply #18 –
Yahoo Message Number: 82669
Dave

On my C-9 it is to the rear and below the radiator. You do need to lay on your back to get a good look at it. My fan controller did not go suddenly but began to work intermittently. When it was not functioning the coach would overhead and the engine would derate. Pulling over to let the engine idle did not work. But turning it off and then back on seem to reset things and fan would come on high and cool down. This was an idea from CC back when. Also, pulling the plug would put the fan into high and get you on down the road.

Dan 2006 Allure 31348

Re: Overheating Cummins 400 ISL

Reply #19 –
Yahoo Message Number: 82679
I had a similar problem with overheating on my 370 ISL. After several visits to three cummins plants and several different tries the cummins plant in Portland discovered my radiator cap was too low in pressure (5-6 lbs} and installed a 15 lb. Problem solved. Just a thought for you to consider.