ISL 400 Engine Specifications

[Old Rv'er]

All - I checked my owners manual and nowhere can I find the following information, so if you have it please post it here. The manual does state to check the dataplate, which I will do once I am at the coach. Thank you in advance. I have not checked cummins web site, that is my next chore.

Red Line RPM
Torque RPM
HP RPM
Normal Operating RPM-Safe operating range.

Thank you in advance.

[Gary RVRoamer]

You can find some of the specs you are looking for on the Cummins site. Since you have a 2007 coach, you probably have the EPA 2007 spec version of the ISL, but the pre-2007 isn't different in RPM or torque (I have a 2003 in a 2004 coach and the numbers are the same).

Cummins Every Time - Motorhome - EPA 07 ISL

http://cumminsengines.com/sites/ever...ection=ratings

The governed speed of the ISL is 2200, which means it won't allow you to exceed that. You can't operate it at an unsafe RPM - it simply will refuse to do it.

[ShapeShifter]

Quote:

Originally Posted by Old Rv'er Red Line RPM Torque RPM HP RPM Normal Operating RPM-Safe operating range.

Gary has a good link, some more information is here: ISL 400 in Motorhomes

From the charts on page 2, it looks like the peak TQ is at 1300 RPM, and peak HP is 2100 rpm. Normal safe operation RPM would be between those two limits.

Like Gary said, the engine/transmission control computers will do their best to prevent you from over-speeding the engine. But one important note in my engine owner manual is to not operate the engine for more than 30 seconds at full throttle while below peak torque RPM. That's probably the most important thing to watch for, as the computer will watch for the high end. The computer should watch the low end, as well, but it doesn't hurt to be vigilant (as I assume you would like to do, since you're asking these questions.)

I put small dots on my tach at 1300 and 2100 RPM, and try to keep the needle between those limits while under load.