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Magnezm · 11-02-2006, 04:59 PM

I am looking at getting a motorhome and am trying to find out more information about engines, etc.

I notice ISB, ISC etc when discussing the diesel pushers. Can anyone explain the differences and what they mean?

Magnezm · 11-02-2006, 04:59 PM

I am looking at getting a motorhome and am trying to find out more information about engines, etc.

I notice ISB, ISC etc when discussing the diesel pushers. Can anyone explain the differences and what they mean?

RV Wizard · 11-02-2006, 11:50 PM

Magnezm, welcome to iRV2.com. We are glad to have you join us here and look forward to reading of your adventures and experieinces. Cummins diesel engines have these letters to differenciate between the sizes of displacment in liters. ISB is 5.9 liters. ISC is 8.3. ISL is 8.9 and so forth. You may want to go to www.cummins.com to find out more. Caterpilar also has abriviations like C9, C10, C12. Good luck and enjoy the hunt.

rebelsbeach · 11-03-2006, 01:30 AM

Magnezm, WELCOME to iRV2!

We look forward to hearing more of your search!

Edmund A Skibinski · 11-03-2006, 01:32 AM

Welcome Magnezm, I hope Mike's explanation is what you were looking for, the letters and letter's and numbers that Cat uses is to designate cubic inch or liter size of the engine. Ed.S

BIGRED1 · 11-03-2006, 04:29 AM

The Cummins naming conventions/designations for their engines seem kind of arbitrary to me. I know by heart that an ISB is a 5.9L engine, an ISC is an 8.3L, etc., but there's nothing in the name itself that will tell you what it is. The largest Cummins engine used in motorhomes is called an ISX, so that is ISB, ISC, ISL and ISX(there may even by an ISM model?). They do seem to follow a convention that the higher the last letter of the engine model name is in the alphabet, the larger the engine, but they're running out of letters. Maybe B in ISB, means baby diesel, C means could use a little more power, L means large, needing even more power, M means Magnum power, and X is Xtra large and even more power :-).

Magnezm · 11-05-2006, 02:20 PM

Thanks everyone for the help.

Gary RVRoamer · 11-06-2006, 04:52 AM

The Cummins and Cat engine model designations meanmore than just displacement, though that is probably the major difference. There will usually also be some technology differences among those models. For example, the ISX has dual overhead cams and an integrated engine brake, while the ISM does not. Some models have turbo chargers and some have optional Jake or exhaust brakes.

Each engine model can have multiple horsepower and torque ratings too, depending on the electronics package used with it and the intended application.

Two Bit · 11-06-2006, 08:54 AM

I dont have a clue as to what those abbreviations mean, but I do know what a Farmall A,B,C,H, & M are.

Hitchhiker · 11-06-2006, 09:59 AM

Sort of like the GM Duramax engines production codes:

<UL TYPE=SQUARE><LI>LB7 = 2001 - 2004
<LI>LLY = 2004.5 - 2005
<LI>LBZ = 2006 - 2007.5
<LI>LMM = 2007.5 - ????[/list]

Ecker · 11-06-2006, 10:53 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Magnezm:
I am looking at getting a motorhome and am trying to find out more information about engines, etc.

I notice ISB, ISC etc when discussing the diesel pushers. Can anyone explain the differences and what they mean? </div></BLOCKQUOTE>

The IS stands for Interact System - it signifies that these engines have full electronic capability to interact with the transmission and other devices. The B/C etc is a carryover from the old days when engines were given letters as released. The main stay of the company for many decades was the H engine with a 5 1/8" bore that was subsequently increased to 5 1/2" and called the NH (for new H) and the capacity was next designator, like NH 425. Then the letter designation with cubic capacity came into vogue like B 5.9 or C 8.3 nut at times they would be called something like C 8.3 250. This fell apart over time as when they released the K6 and K12 in the 70's obviously designating cylinders but again there was literature that would say K450 or KT 500 (T being turbocharged) Then when they redesigned each engine they retained the letter and adopted the HP thus the B 5.9 mechanical became with the Interact system ISB 275 or ISC 325. As the HP kept growing and new engines emerged they added new letters like ISL 400,ISM 500,ISX 600 etc. There are difference in these designations by vocation so its important when looking at spec. data sheets to make sure your looking at data for ISM 500 Recreational engine. Confusing and hard to explain but I hope it helps.

Toby · 11-06-2006, 12:51 PM

As long as your at it, What is a Dodge HEMI? I've asked several of my friends (one who has one) and no one seems to know. s/Toby

Ecker · 11-06-2006, 03:15 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ecker:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Toby:
As long as your at it, What is a Dodge HEMI? I've asked several of my friends (one who has one) and no one seems to know. s/Toby </div></BLOCKQUOTE>

For a guy my age and a race fan that's an easy one - I was there at its birth. The cylinder combustion chamber is hemispherical - thus hemi

See this for a complete explanation

http://auto.howstuffworks.com/hemi.htm </div></BLOCKQUOTE>

Toby · 11-07-2006, 04:04 AM

Ecker

That was very interesting. Now I'll be able to impress my friends on "all" my knowledge.
I'm of the age that when working on engines, I knew that if you got the gas to the spark and there was air, The engine would run. Now-a-days, I don't even know where to start. s/Toby