Skip to main content ↑ ↓
Topic: Critical temperatures and pressures (Read 980 times) previous topic - next topic

Critical temperatures and pressures

What are the high or low temperatures or pressures that should never be exceeded for the following in a Cummins M11 450 HP?

Transmission

Engine

Oil

Oil temperature

Battery

Tachometer

Air pressure

I'm looking for numbers that would tell me that it is time to slow down, or to stop or to take a necessary action to stop damage from happening.
George Stoltz.  Retired from full-time living in a great Foretravel and now are back to living in a traditional sticks and bricks in Florida.

Re: Critical temperatures and pressures

Reply #1 –
George, like Tim said, "relax a bit".  There should be warning systems already built into the coach to alert you of dangerous levels, or temperatures.  I know your fluids are changed as specified, so you don't need to be concerned about "breakdown" of fluid properties due to high temperatures or abuse.  Remember that if any of your gauges or monitoring systems are showing readings that you've never encountered under normal driving conditions, then you should be cautious at that time to ensure the condition does not deteriorate.  If no improvement is noticed as you continue to drive, then at the next available stopping point, you should begin a shake down to determine the cause of the excessive reading, whether its coolant temperaturem, trans. temp, low oil pressure, low air pressure, etc.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Critical temperatures and pressures

Reply #2 –
I agree with Peter.

What you are looking for is any ABnormal readings/changes in readings.  Those are the first warning signs of problems.

Said another way, it is really not critical if your engine operating temperature (thermostatic control) is 190 or 195, but if it changes from one to the other, THEN determine the reason.

Brett Wolfe
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Critical temperatures and pressures

Reply #3 –
Quote
I'm looking for numbers that would tell me that it is time to slow down, or to stop or to take a necessary action to stop damage from happening.

George,
I have a listing of my engine Specifications :
Should be close to yours

http://beamalarm.com/Documents/2003_foretravel_u320_cummins_450_readings.html
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"
 

Re: Critical temperatures and pressures

Reply #4 –
There are a lot of warning systems in newer engines and transmissions that don't exist with the older ones so that in some sense the computer worries for you.  It certainly does not hurt to keep an eye on things.  In my '91 Grand Villa I've noticed that the only time the trans temp climbs is in city traffic.  Since I have manual gauges I've put a small colored piece of tape at the upper limit of the gauges from information provided by Caterpillar and Allison.  I've done the same thing with the speedometer because in some light with sunglasses on you cannot read the numbers.
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP