Cummins ISC 350hp Valve Adjustment Schedule

Donna and Rob wrote:
I think Mr.Mark's about right 250,000 and 15,000 on oil change but I change mine about every 3-4000.

You only need to do it at 15000 miles or annually. I run oil analysis on my engine and at 12,000 miles the oil showed good for another 10,000 miles but I change annually per Cummins guide. I do run 5-40 Mobil 1 Turbo Diesel. But it's your money and you can spend it any way you want. I would rather by fuel.
Bill

supercub wrote:
I have just under 30K miles.........but it's 10 years old........how important is the 4 year interval? Why would you need to adjust the valves if the engine sat for 4 years........what could change. I can understand mileage or amount of hours the engine has run, but year? Should I have the adjusted with just 30k miles? and 10 years old?
Thanks
Brian

You have no need to adjust them until the miles build up. Time alone does nothing.

FWIW, I adjusted mine at 50K anyway and they were all well within. I adjusted them so they were all exactly the same but it didn't make any difference in performance, sound or fuel efficiency.

When I had my ISC, this was the schedule I ran close to.

Maintenance Schedule (CAPS or HPCR Fuel System)
Oil & Filter
15,000 Miles, 500 Hours, or 6 Months (I did once a year.)

Fuel Filter
15,000 Miles, 500 Hours, or 6 Months (I did once a year.)

Valve Adjustment
150,000 Miles, 5000 Hours, or 4 Years (Coach was a 2001, I had them checked once after 2 years, found only one needed adjustment.)

Valve clearances do not change based on time. The change based on miles/wear of mechanical components.

And, yes 150,000 miles is the official answer from Cummins with the additional statement that these engines tolerate a WIDE range of clearances with no adverse affect on performance.

supercub wrote:
I have just under 30K miles.........but it's 10 years old........how important is the 4 year interval? Why would you need to adjust the valves if the engine sat for 4 years........what could change. I can understand mileage or amount of hours the engine has run, but year? Should I have the adjusted with just 30k miles? and 10 years old?
Thanks
Brian

I'm with you on the age of the motor Brian. I have 34K on the clock and have no plan to have the valve lash adjusted.

I have just under 30K miles.........but it's 10 years old........how important is the 4 year interval? Why would you need to adjust the valves if the engine sat for 4 years........what could change. I can understand mileage or amount of hours the engine has run, but year? Should I have the adjusted with just 30k miles? and 10 years old?
Thanks
Brian

Yes, 150K but it's a very easy job and won't hurt anything if you check them early.

Valve Adjustment 150,000 Miles, 5000 Hours, or 4 Years

http://www.diesel-service-parts.com/cummins-isc.html

I think Mr.Mark's about right 250,000 and 15,000 on oil change but I change mine about every 3-4000.

The Cummins guy told me 250,000 miles (425 hp ISL).

(2008 Dynasty with just shy of 70,000 miles).
MM.