Community Forums

Flick · 10-18-2016, 04:38 AM

I have a 2003 Dutch Star, Spartan chassis Cummings ISC 350hp. Last trip it appears to be losing power on grades. Speeds decrease to 40 mph. Although some may say this is expected, I've not seen this decrease even on steeper grades. I'm thinking fuel filters. Any other thoughts?

twinboat · 10-18-2016, 05:00 AM

Unless you look over the engine compartment and find any of the CAC pipe connectors loose or torn, your thinking of fuel filters is correct.

In my experience, they are the leading cause of power loss in diesel engines.

Any time we went out to the field on a low power issue, we made sure we had filters with us. Most times it was the problem.

NHRA225 · 10-18-2016, 05:07 AM

Might also look at the Air Filter .

jacwjames · 10-18-2016, 07:05 AM

Are you maintaining boost pressure on the turbo?

Dr4Film · 10-18-2016, 07:11 AM

The first and cheapest attempt to correct your problem is to change both the primary and secondary fuel filters.

After that more troubleshooting will be needed and it may end up to be more expensive too unless you find a leaking clamp, etc.

Dr4Film ----- Richard

JohnBoyToo · 10-18-2016, 07:24 AM

fuel filters fixed our power loss that would eventually give us a 'hiccup' from fuel starvation.

**CountryFit** · 10-18-2016, 08:40 PM

while focusing on fuel filters and air filter, also check transmission fluid level, just in case.

Flick · 10-19-2016, 12:42 PM

Thanks for all the replies. I'll change the fuel filters 1st.
Jim J.- pretty sure mine isn't turbo charged, at least there is no booster gauge. My understanding is Cummings started that later in 2003.

Mr_D · 10-19-2016, 12:46 PM

Quote:

Originally Posted by Flick

Thanks for all the replies. I'll change the fuel filters 1st.
Jim J.- pretty sure mine isn't turbo charged, at least there is no booster gauge. My understanding is Cummings started that later in 2003.

All ISC's are turbo charged so you have one even though there's no boost gauge. Our '02 DSDP 4090 had a turbo but no gauge till I installed the Banks kit.

Mike_Harriet · 10-19-2016, 05:29 PM

My 350 ISC did the same. Fuel filter looked okay, but changed fuel and air filters and performance greatly improved. After the fact, I remembered to check the diagnostics on my VMSpc, and behold, reduced fuel flow/pressure popped up. Could've saved by not replacing air filter. My old brain wasn't as quick on the uptake as a thought.

WILDEBILL308 · 10-19-2016, 06:22 PM

Quote:

Originally Posted by Flick

Thanks for all the replies. I'll change the fuel filters 1st.
Jim J.- pretty sure mine isn't turbo charged, at least there is no booster gauge. My understanding is Cummings started that later in 2003.

One of the best investments would be a good boost and a good EGT gage.

Bill

Ready2Travel · 10-30-2016, 06:12 PM

Pulling a 4800 lb toad 40 in 3rd gear was about all my 350 ISC would do in my 2004 Winnebago. The new heavier Entegra with an ISL will go 50 in 4th gear up the same grades.

NHRA225 · 10-31-2016, 06:40 PM

Quote:

Originally Posted by Ready2Travel

Pulling a 4800 lb toad 40 in 3rd gear was about all my 350 ISC would do in my 2004 Winnebago. The new heavier Entegra with an ISL will go 50 in 4th gear up the same grades.

I Pull a 10K enclosed Race Trailer all over East of the Mississippi.
My 6CTA is up-graded from 300 HP to 450 HP and I can climb any Grade at almost any speed I want . My EGT's on the incline go to 1250 and on the Flats She run's at 950 deg- very consistent.
I change ALL of my Filters Every 6K Miles ! Just Me !

Maik · 11-02-2016, 01:36 PM

I just recently changed fuel and air filters; in preparation for a long trip in December. Unfortunately I changed the primary filter only and took the MH for a drive. Found high EGT and checked causes with a thread on this forum. Located secondary filter and air filter and changed both. MH now has lots of power I did not know it had. We just purchased the MH this last July, thinking that the dealership had serviced it. Apparently NOT! The 325 hp 8.3 ISC is plenty of power for me and the family.