Cummins 350 ISC Lurching Under Load

[kstark65]

Have a 2004 Fleetwood excursion 39l, has a Cummins isc350.  Just bought it used.   First big trip ran great on way out, then about 300 miles into return trip starting chugging as we came into Sioux Falls.  Check engine line flashed but went off.  Made it to an exit.  Seemed to run OK at city street speeds.  Came to a gas station.  Filled up and headed back out.  Ran fine till got to about 50 miles.  Then started chugging again.  Pulled over called good Sam.  Gave me the names of about ten repair places.  Begged for Cummins number.  Finally got that.  They sent me to another Cummins shop because they couldn't get me in.  Now here 3 days.  

Fault code didn't reveal magic answer and haven't been able to get it to throw a new code.  Ran that first night with computer hooked up while driving.  Mechanic said could see it calling for appropriate pressure but delivery dropping.  Changed both fuel filters both before we left and as early try at repair.  After much diagnosis time with no answers had them change low pressure fuel pump. Better but problem still recurs although it seems to be less dramatic.   Mechanic said line from tank to pump not obstructed.  He drove it last night for about 40 miles.  Went long stretches without problem recurring but it did happen sporadically .

 Read through some posts and saw conversations on PAC brake.   Found it and it appears to be fully retracted.  Wasn't using it at the time.  

Supposed to have their Cummins and RV expert here tomorrow so hoping he can figure it out.  Been pretty impressed with quality of answers on here so I thought I'd see if you had any words of wisdom.  Thanks in advance.  

 

Ken

 

[wildebill308]

Ken, welcome to the forum. Are you saying they changed filters after Cummins started to troubleshoot?

"Mechanic said could see it calling for appropriate pressure but delivery dropping." I hate  to say it but my SWAG is filters or fuel pump. Let us know what the expert finds.

Bill

[dickandlois]

Ken, welcome to the forum! Well you have eliminated to fuel filters and lift pump. What fault code did you get ?

How many miles on the coach?

Has the coach set idle for an extended period of time? 

Look at this link and ask some questions about the setup on your engine>

Rich.

[kstark65]

1 hour ago, WILDEBILL308 said:

Ken, welcome to the forum. Are you saying they changed filters after Cummins started to troubleshoot?

"Mechanic said could see it calling for appropriate pressure but delivery dropping." I hate  to say it but my SWAG is filters or fuel pump. Let us know what the expert finds.

Bill

Yea that was poorly worded on my part.   Actually replaced filters before we left on the trip.   Then after mechanic rode in it we changed them again as a cheap stab at it.

 

Also forgot to mention I called freightliner and they tell me I don't have the third inline filter that others have found.  They said only he ISB had that. 

Since we replaced the low pressure pump, mostly it seems like they have been trying to rule out the high pressure pump and the multi thousand dollar expense that comes with it.  

I will let you know what they eventually come up with.  

[kstark65]

2 hours ago, WILDEBILL308 said:

Ken, welcome to the forum. Are you saying they changed filters after Cummins started to troubleshoot?

"Mechanic said could see it calling for appropriate pressure but delivery dropping." I hate  to say it but my SWAG is filters or fuel pump. Let us know what the expert finds.

Bill

Yea that was poorly worded on my part.   Actually replaced filters before we left on the trip.   Then after mechanic rode in it we changed them again as a cheap stab at it.

 

Also forgot to mention I called freightliner and they tell me I don't have the third inline filter that others have found.  They said only he ISB had that. 

Since we replaced the low pressure pump, mostly it seems like they have been trying to rule out the high pressure pump and the multi thousand dollar expense that comes with it.  

I will let you know what they eventually come up with.  

[kstark65]

1 hour ago, DickandLois said:

Ken, welcome to the forum! Well you have eliminated to fuel filters and lift pump. What fault code did you get ?

How many miles on the coach?

Has the coach set idle for an extended period of time? 

Look at this link and ask some questions about the setup on your engine>

Rich.

Rich,

Kicking myself for not writing down the code he got. Wasn't expecting this mess.  I will try to get it tomorrow.   But as I recall the suggestions check for wiring issue and/or fuel sensor/sending unit.

Just rolled over 70000.

Previous owner said it sat over the winter.  But can't say for sure if it wasn't longer.  

I read through the link.  I have a call into freightliner on the caps vs hpcr. I will let you know what I find.  

It does sound a bit like the issues others have had but haven't had the stalling. Mechanic had it on extended test drive after replacing low pressure fuel pump.  Trying to get it throw a fault code.  Said when it acted up he just kept pedal down and while didn't act right at the time it would settle down once the load seemed to be off - no more hill, it seemed to be ok.  

Ken

PS sorry for the multiple responses. Phone and forum not getting along.

[dickandlois]

Ken, We all started out missing things an every coach owner is still on a learning curve. Just that some have been on the curve longer an know that they have been there and done that before more often. 

Freightliner can give you the engine serial number, then you can contact Cummings and they will fill in how the engine was configured when it was shipped to Freightliner.

Keep your engine serial number, transmission serial number and Vin numbers handy. Also you might want to join the Cummings power Club. They knock off 10% for parts and labor. That adds up fast.

Most of the mechanical if not all of the replacement ones are rebuilds, so let the group know if that is what needs to be replaced. Some rebuilds are better then others. Ask if they mind installing something other then there's if that comes up.

Rich.  

[kstark65]

Rich,  thanks for your help and encouraging words. It does help.  

So far this morning found out from Cummins that it has the CAPS.

With a little bit of whining on Saturday they did give me what seems to be the equivalent to the cummins power club discount.  I suspect the big argument is going to be over diagnostic labor costs.  

No luck on original fault code but the mechanic today is apparently the shop recognized Cummins and RV expert.  Apparently most other deal primarily with Cat's.  Already seems more focused and not running back to the computer after every step which is encouraging.  Maybe misguided but right now I am looking for any sign we are moving towards me being able to head home. 

Thanks again.  

[kstark65]

Just to follow up.  

Yesterday, the Cummins expert was there. Started work at about 7.  By 9:30 he had found a clogged fuel line to the low pressure pump.  Said it ran from bulkhead to the low pressure pump.  Only about a foot maybe 18" long. By 11 had it replaced and completes a 50 mile test drive to make sure.  

Waited over an hour for the invoice.  Which they cut down from $3600 to $2700 with some discounts on parts and charging me truck labor rate instead of RV rate.  14 hours and 900 miles later I was home.  

As I was getting ready to leave I  talked with guy who had replaced lower pressure pump.  We looked at the clogged hose.  He knew exactly where was from.  He had loosened it from the old pump and put it on the new one.   Never bothered to look in it.  Probably a good thing I had been there so long and was just ready to leave.  He had told me repeatedly they had confirmed the line was clear from the tank to the low pressure pump.  Obviously it wasn't.  I do suspect that is why they gave so much on the bill without batting an eye and they weren't budging an inch with the truckers.  

Since I had 14 hours of alone time to let my mind wander, I did think of something that should have been a red flag.  When we bought the unit I noticed the fuel filter that is visible by the rear radiator was all rusty.  I assume that it was just a case and there was a drop in filter of some sort.  But now that I have seen the condition that new filters are in, I suspect it had been on there for a very long time.  

Have been told I should use an anti algae treatment and be aggressive with changing the filters.  Possibly look at having tank cleaned.   Need some more sleep before deciding. 

Thanks again for the help and suggestions.  

Ken

[dickandlois]

Ken, It is always good to get a response from owners on there experience.  The feedback adds to the information available to all the members who read the threads.

I agree that it would be helpful to add some Bioside to each tank and keep replacement filters on board. The algae is a black slime and will collect in the filters. You might want to consider replacing the fuel filter on the generator if it runs on Diesel also.

Did you add the Cummings Power Club membership to your file folder. They do come in handy and the discount is also a plus.

Good to know that you got home safe, running for 14 hrs. is a long time to be driving.

 Rich.

[wildebill308]

Ken, Glad you got home safe. That would have been a 3 day run for me. 

I hope they comped the new fuel pump and the labor as it was their mistake. 

Did they say it was algae clogging the hose? I would run a bottle of Diesel Kleen and once in awhile a bottle of the biocide to keep the algae under control. I doubt you will have a problem with gelling in the summer. Having a couple extra filters is always a good thing. As you have heard the first thing recommended if you have a problem is "change the filters".

Bill

[kstark65]

4 hours ago, DickandLois said:

Ken, It is always good to get a response from owners on there experience.  The feedback adds to the information available to all the members who read the threads.

I agree that it would be helpful to add some Bioside to each tank and keep replacement filters on board. The algae is a black slime and will collect in the filters. You might want to consider replacing the fuel filter on the generator if it runs on Diesel also.

Did you add the Cummings Power Club membership to your file folder. They do come in handy and the discount is also a plus.

Good to know that you got home safe, running for 14 hrs. is a long time to be driving.

 Rich.

Just joined the cummins power club this evening.  Tried to give you credit, but didn't have your last same.  Not sure what you get for the referral but in case it's good stuff I put in your name as Rich of Dickandlois on Fmca as your first name and Dickandlois Lois on Fmca as the last name.  You may want to check with them if they do give away good stuff for referrals.

I'll get some biocide and extra filters, asap.

[kstark65]

1 hour ago, WILDEBILL308 said:

Ken, Glad you got home safe. That would have been a 3 day run for me. 

I hope they comped the new fuel pump and the labor as it was their mistake. 

Did they say it was algae clogging the hose? I would run a bottle of Diesel Kleen and once in awhile a bottle of the biocide to keep the algae under control. I doubt you will have a problem with gelling in the summer. Having a couple extra filters is always a good thing. As you have heard the first thing recommended if you have a problem is "change the filters".

Bill

We had planned to be 2.5 days with some touristy stuff along the way, but needed to get back to work.  Unfortunately have to pay for the new toy.

Didn't directly comp pump, but what they did works out pretty close.  Biggest thing they did was lowering the labor rate from their normal rv rate which was $140 an hour to the truck rate of $114 an hour.  And he cut off some of the hours.  Still had $1938 in labor.  I really just asked if there was any relief I could get.  I took it as the shop foreman's implied admission that the previous shifts hadnt done very good with this one.   He could hide the labor but the invoice from cummins on the part.  Given that I had heard the big boss lay into some poor clerk for printing out a one page government form in color instead of black and white, i figured I wasn't going to get much more than a later departure time and higher blood pressure.

Didnt say what it was but i have the hose.  I'll see if i can dig it out.  Some kind of slimy looking black blob.  Even if its not, seems like the treatment is a good preventive measure.  Thanks for the confirmation on the filters and biocide.   I appreciate the advice, help and well wishes.

Ken

[jleamont]

Ken, how does it run now? See the link below from my similar dilemma two years ago, my blob was the fuel line breaking down and passing into the filter. Does your coach have rubber fuel lines? I had crud in my filter bowl also, just purchased the coach and only put 200 miles on it at the time and thought it ran decent, come to find out the line from the tank to the filter deteriorating and rubber was passing into the filter, it was slimy like jelly. I thought it was algae turns out it was the rubber breaking down. the tell tale sign was one piece had some roughness to it, after I really looked at it I realized it was fuel line material. I eventually noticed fuel smell in the basement area as they got worse they also began to leak, once that occurred I was pulling too much air for it to run.

The fuel pump replacement was good insurance, I changed mine also when I found out they had problems that leaded to CAPS pump problems down the road. Cummins has problems with those lift pumps....to the point it has been redesigned several times and they finally got it right in 2010.

 

[kstark65]

46 minutes ago, jleamont said:

Ken, how does it run now? See the link below from my similar dilemma two years ago, my blob was the fuel line breaking down and passing into the filter. Does your coach have rubber fuel lines? I had crud in my filter bowl also, just purchased the coach and only put 200 miles on it at the time and thought it ran decent, come to find out the line from the tank to the filter deteriorating and rubber was passing into the filter, it was slimy like jelly. I thought it was algae turns out it was the rubber breaking down. the tell tale sign was one piece had some roughness to it, after I really looked at it I realized it was fuel line material. I eventually noticed fuel smell in the basement area as they got worse they also began to leak, once that occurred I was pulling too much air for it to run.

The fuel pump replacement was good insurance, I changed mine also when I found out they had problems that leaded to CAPS pump problems down the road. Cummins has problems with those lift pumps....to the point it has been redesigned several times and they finally got it right in 2010.

 

It ran good for the 900 mile drive home.  But then again it ran good for the 1500 miles up to the point that it didn't anymore.  I will definitely make a concerted attempt to get to the blob in the hose and see if I can figure out what it is.  Never thought I'd be saying, that I am hoping its algae, but I am.

Sounds like you had quite the job on your hands.

From what I have seen and been told, there is quite the mish-mash of lines.  No idea what is original and what was replaced by a previous owner.  The line from the tank to the rear is a plastic line.  There are some what appear to be fairly routine rubber hydraulic lines.  The one with the blob is a rubber line with a wire mesh casing on the exterior.

While I wasn't happy about the timing, the price or finding out that they hadn't really checked all of the lines, I am not the least bit unhappy about having the new pump in there.  Based on everything I had read, it seemed like a pretty safe move.  Particularly when reading that these pumps lead to problems with the high pressure pump.

Thank you for the tips on the rubber lines.  Definitely something to keep my eye on.  I appreciate the help lowering the slope of my learning curve.

Ken