Cummins ISL 370 chugged, died, and won't restart.

[TR4]

Originally Posted by Fefanatic

I was up until 3:00 am this morning going over the quickserve site and may have a solution.

Two years ago I had to replace the lift pump due to getting bad fuel with algae in it. The algae actually locked the pump up and I couldn't save it. Inside the pump is a check valve that opens once the engine is running and the lift pump stops pumping. It's possible that the check valve is clogged. If so it's not serviceable and I need to buy another lift pump.

Newmar when they manufactured this unit did not put a fuel filter in front of the lift pump. The fuel system goes from tank to lift pump, fuel filter, caps, and return to tank. The lift pump gets unfiltered fuel and is susceptible to damage from debris. It's a major pain to remove but I hope to do it today.


The lift pump can be pumping without the valve operating properly so if it's not that then I have a major caps pump issue. Neither solution is cheap.

I thought you said on post #3 that you removed the fuel line going to the CAPS and there was a lot of fuel volume. Was there air in the fuel? Did you check the fuel pressure while the lift pump was running?

Just wondering if you’re pulling air into the fuel lines. I think QuickServe details how to check the gear pump pressure. Also, I think I remember seeing a screen on the CAPS intake, maybe clogged?

These pumps get damaged quickly if they’re starved of fuel (you said you had a prior problem). Many here have added a full time pump. I installed a Fass pump many years ago along with a fuel pressure gauge. I also use Opti-Lube XL to help with lubrication of he pump. These CAPS need all the help they can get.

Bill

[Mile Marker 42]

Originally Posted by Fefanatic

I was up until 3:00 am this morning going over the quickserve site and may have a solution.

Two years ago I had to replace the lift pump due to getting bad fuel with algae in it. The algae actually locked the pump up and I couldn't save it. Inside the pump is a check valve that opens once the engine is running and the lift pump stops pumping. It's possible that the check valve is clogged. If so it's not serviceable and I need to buy another lift pump.

Newmar when they manufactured this unit did not put a fuel filter in front of the lift pump. The fuel system goes from tank to lift pump, fuel filter, caps, and return to tank. The lift pump gets unfiltered fuel and is susceptible to damage from debris. It's a major pain to remove but I hope to do it today.

The lift pump can be pumping without the valve operating properly so if it's not that then I have a major caps pump issue. Neither solution is cheap.

That would be strange about the check valve since you said you have plenty of fuel coming out of the lift pump. Even stranger that your coach was built with filters all after the lift pump. I like many installed a AirDog only pump above my fuel tank and push fuel to my 2 factory fuel filters. I did a little re-routing of the fuel filters so now they are side by side. I bypassed the factory lift pump. I even installed a Goldenrod filter before the AirDog pump. I also installed a fuel gauge inside on the dash. Keep us posted. Rooting for you

[Fefanatic]

Originally Posted by Mile Marker 42

That would be strange about the check valve since you said you have plenty of fuel coming out of the lift pump. Even stranger that your coach was built with filters all after the lift pump. I like many installed a AirDog only pump above my fuel tank and push fuel to my 2 factory fuel filters. I did a little re-routing of the fuel filters so now they are side by side. I bypassed the factory lift pump. I even installed a Goldenrod filter before the AirDog pump. I also installed a fuel gauge inside on the dash. Keep us posted. Rooting for you

The check valve would work independently from the pump. When the pump is running the check valve has pressure on the back side keeping it closed so fuel doesn't get pumped back into the inlet line. Once the engine is running the caps would try to draw fuel through the valve and it would open to allow fuel flow from the tank.

I now know the valve is not clogged. I tried the Bluefire ap, updated the firmward on the bluetooth adapter and checked for codes again. No codes.

I remembered a set of 3 switches that are diagnostic switches under the dash and I activated them. i had the check engine light on the dash flash once and then a red icon flash 3 times about a second apart. I read that to mean code 111 and if that's the case I am going to be looking at a ecm replacement. I have to do further research before I break down and spend anywhere from $1500-$3000 on a replacement.

I'm not sure investing in the Bluefire system was such a great idea.

I tried to reset the 111 code but since Bluefire doesn't see any codes it won't clear any codes.

[jacwjames]

You might check the Cummins Quickserve site for the fault code and see what steps is recommends for troubleshooting.



On my coach I have 3 fuse holders that are part of the ECM wiring, ~7 fuses, one of the fuses is for the diagnostics. Wonder if the fuse could be blown causing the fault code.

[Fefanatic]

Update: I have confirmed that there is good fuel flow into the accumulator head. The pump camshaft and lifters are good. When cranking with the accumulator head off there is good lift pump pressure, and the fuel control valve is working. As it cranked the fuel would pulsate with the ecm pulsing the fuel valve. So, unfortunately all that cranking was hard on the starter, and it started to fail. I have a new starter on the way and will get it installed after this next snowstorm.

So I plan to inspect t he accumulator internals to see if there is anything that has excessively worn or broken. I don't think it's pumping out high enough pressure to run the engine.

As far as the ecm goes, I still can't pull any codes and the light on the dash still blinks 3 times once every second or so. With the pump pulsing the fuel control valve I am not convinced the ecm is bad yet. I do have a mobile mechanic with Cummins analyzer coming to check the ecm.

Will update once I have that information.

[Mile Marker 42]

Originally Posted by Fefanatic

Update: I have confirmed that there is good fuel flow into the accumulator head. The pump camshaft and lifters are good. When cranking with the accumulator head off there is good lift pump pressure, and the fuel control valve is working. As it cranked the fuel would pulsate with the ecm pulsing the fuel valve. So, unfortunately all that cranking was hard on the starter, and it started to fail. I have a new starter on the way and will get it installed after this next snowstorm.

So I plan to inspect t he accumulator internals to see if there is anything that has excessively worn or broken. I don't think it's pumping out high enough pressure to run the engine.

As far as the ecm goes, I still can't pull any codes and the light on the dash still blinks 3 times once every second or so. With the pump pulsing the fuel control valve I am not convinced the ecm is bad yet. I do have a mobile mechanic with Cummins analyzer coming to check the ecm.

Will update once I have that information.

Way to hang in there I am rooting for you. Keep after it.

[Fefanatic]

So, the bad news. I suspect the fuel pressure sensor may be bad, so I wanted to remove it and get a look at it. I tried to mount the accumulator in a vice and dropped that heavy thing. It broke the fuel pressure sensor. A new one is on the way at $349.00.

So, the good news. I took the starter to a local rebuild shop and he didn't have one on the shelf. But he did have a dump truck starter for a Cummins, and it had a different gear head on it. He told me to take it and swap the motor on the heads and it should work. Great!! I did. I called him back up and told him it works, and he charged me $40.00 for the parts. So, where I lost on one thing it came back to me in another.

As soon as the fuel pressure sensor shows up and the snow that's on the way right now clears up, I will be right back on this project. Will update then.

[Doug427]

Fefanatic - Completely off topic, but you get a lot of snow! Where are you at?


Also, I see your name is Fefanatic - would that by chance be the Ford FE engine? 520 cu. in. sideoiler owner here. If not, then disregard.


Sorry for the off topic, back to the main point of the thread. Good luck tracking down your issue.

[TR4]

Thanks for keeping us updated. It’s great that you can replace components to get it running. Most shops will only replace the entire pump with a rebuilt unit. If you could take some pictures of your progress, it might help others willing to attempt this. Your a brave guy, I wish you luck!

Bill

[Fefanatic]

Originally Posted by Doug427

Fefanatic - Completely off topic, but you get a lot of snow! Where are you at?


Also, I see your name is Fefanatic - would that by chance be the Ford FE engine? 520 cu. in. sideoiler owner here. If not, then disregard.


Sorry for the off topic, back to the main point of the thread. Good luck tracking down your issue.

I'm right outside of Kansas City and it's snowing right now. And yes, most people don't get the correlation. FE is for FE I've owned my share of Galaxies and Mustangs with 406, 427, and 428's. The sad part is I didn't realize at the time the value they would have today.

[Fefanatic]

Let's do another update.

So. last Sunday was a decent enough day to crawl back under the coach and replace the starter. I managed to get that job done, installed the new fuel pressure sensor in the accumulator head and put the whole thing back together.

Engine spins great and will start only to die again. White smoke from unburned diesel.

I decided to eliminate all the fuel system and went to the local parts house and purchased enough fuel line adapters to rig a separate fuel source from a fuel can. I bought a cap for the fuel line coming from the lift pump so it wouldn't be pumping fuel while cranking or running. I installed a fuel line and fuel pump to the input of the caps pump and ran a separate fuel pump from the fuel can to the caps.

Again, it would start or roll over to the point it wanted to start but just couldn't stay running. It was a fresh can of diesel, so I also eliminated the fuel being an issue.

I decided to pull the ecm and send it in to Cummins. They told me they could check to see if it communicates but not be able to confirm whether it is the issue or not.

So, I got the report from Cummins today. They gave me a printout of all the history codes stored in the computer. It was three pages worth. Everything from low power to engine fuel temperature, to code 1 1 1 that I have been worried about. They would not tell me one way or the other if the ecm is bad or not.

To be fair some of those codes were caused by me during diagnostics. They also told me that they would charge $400.00 to program a new computer if and when I purchase it, even from them.

I mentioned that I am ready to have it towed to them and the service manager told me he doesn't have an engine mechanic right now. Not sure when he will have one so don't be towing it to him yet.

I am in a quandry right now. I have decided to fine a mobile service mechanic with a Cummins insite diagnostic tool to come and run some tests and see if we can pin down the issue before I start spending thousands of $$ on parts that may not resolve the issue.

Now, for all you out there that want to tell me about Blue Fire and their adapter you can save your keyboard breath. There were 16 separate codes in that ecm that Bluefire failed to display. As far as I am concerned it's worthless and I plan to sell mine and get something else.

I've emailed Bluefire in the past and do not get a response.

So, yesterday was 68 degrees and today it's 15 degrees so any future work is on hold until it warms up again.

I will keep you posted on any further developments.

[randomledder]

When you had the accumulator off did you inspect the plungers in the accumulator? Also wondering if you checked the fuel pump tappers (followers). As I have seen a few of these stuck and a couple in sideways. I would be curious what the commanded versus the actual fuel pump pressure is when it’s cranking. Have you checked gear pump pressure?

[Fefanatic]

Originally Posted by randomledder

When you had the accumulator off did you inspect the plungers in the accumulator? Also wondering if you checked the fuel pump tappers (followers). As I have seen a few of these stuck and a couple in sideways. I would be curious what the commanded versus the actual fuel pump pressure is when it’s cranking. Have you checked gear pump pressure?

Tappers looked good. I had them out and spun the engine to check the camshaft lobes and didn't find any issues. Rollers on the bottom of tappers were good and the plungers are tight in the bores. There was no wear nor was there any indication that fuel was leaking past them. Trying to check the gear pump pressure wasn't something I tried to do while cranking since during cranking the lift pump was running and supplying pressure.

I did crank it with the accumulator off the pump assembly and saw that the fuel was pulsing when the fuel control valve was being excited by the ecm. Trying to hold the pressure back with finger pressure was impossible.

What I need now is to be able to read fuel pressure, commanded pressure, and other data to determine if the ecm is functioning properly.

What I am down to is not knowing if it's the ecm or the accumulator as those are the last two things I've boiled it down to. The ecm commands the accumulator which supplies the high fuel pressure to injectors. If the ecm is commanding the accumulator, then it's the accumulator that's bad. In that case I will replace the whole caps assy since the accumulator isn't available as a separate serviceable item.

[Mile Marker 42]

Originally Posted by Fefanatic

Let's do another update.

So. last Sunday was a decent enough day to crawl back under the coach and replace the starter. I managed to get that job done, installed the new fuel pressure sensor in the accumulator head and put the whole thing back together.

Engine spins great and will start only to die again. White smoke from unburned diesel.

I decided to eliminate all the fuel system and went to the local parts house and purchased enough fuel line adapters to rig a separate fuel source from a fuel can. I bought a cap for the fuel line coming from the lift pump so it wouldn't be pumping fuel while cranking or running. I installed a fuel line and fuel pump to the input of the caps pump and ran a separate fuel pump from the fuel can to the caps.

Again, it would start or roll over to the point it wanted to start but just couldn't stay running. It was a fresh can of diesel, so I also eliminated the fuel being an issue.

I decided to pull the ecm and send it in to Cummins. They told me they could check to see if it communicates but not be able to confirm whether it is the issue or not.

So, I got the report from Cummins today. They gave me a printout of all the history codes stored in the computer. It was three pages worth. Everything from low power to engine fuel temperature, to code 1 1 1 that I have been worried about. They would not tell me one way or the other if the ecm is bad or not.

To be fair some of those codes were caused by me during diagnostics. They also told me that they would charge $400.00 to program a new computer if and when I purchase it, even from them.

I mentioned that I am ready to have it towed to them and the service manager told me he doesn't have an engine mechanic right now. Not sure when he will have one so don't be towing it to him yet.

I am in a quandry right now. I have decided to fine a mobile service mechanic with a Cummins insite diagnostic tool to come and run some tests and see if we can pin down the issue before I start spending thousands of $$ on parts that may not resolve the issue.

Now, for all you out there that want to tell me about Blue Fire and their adapter you can save your keyboard breath. There were 16 separate codes in that ecm that Bluefire failed to display. As far as I am concerned it's worthless and I plan to sell mine and get something else.

I've emailed Bluefire in the past and do not get a response.

So, yesterday was 68 degrees and today it's 15 degrees so any future work is on hold until it warms up again.

I will keep you posted on any further developments.

Man, I feel for you. This is way above my pay grade. Do you think you have air in the fuel system? Is it worth cracking a fuel injector to let any air out, or see if fuel is coming through? A guy named Frank was coming through CO last winter getting ready to climb a 10% grade with very low fuel. I think his lift pump was leaking too. He had to get towed off the freeway and it took him almost a month to get out of there. Multiple mobile mechanics etc etc. Had a rebuilt CAPS pump flown in and a mobile mechanic replaced it and he finally made it out. He had a big post here on it. It is because of him that many of us with the lift pump engine decided to remove of disable the lift pump and upgrade to a Fass or AirDog pump. Here's to hoping you get her running soon.