I got a new 6.9 and while driving it home it started to loose power and then it chugged and bogged down bad. It would bounce back and forth as if the throttle was being shut on and off. The only way I could get it to run without bouncing back and forth was to rev above 2500 rpm and clutch out slowish. Then it died. I parked it for 5 mins and started it up and it ran fine for another 5 minutes but then started having issues again as I pulled into the drive. It ran one more time fine for about 15 minutes that day after I parked it for a while. The next day I started it and immediately it had a real rough idle and was throwing tons of blue white smoke. I could barely move it around before it would die. Now a week later it wont start but if it does it will turn over once or chug twice. If i hold throttle wide open it will rev up to about 2000 rpm then die like it has no fuel.

I have run a Jerry can test with the fuel line from the lift pump and return line from the back of the engine put in the temporary fuel tank.

I have purged and cleaned every line running from the fuel tank selector valve to the engine. (Shouldnt matter with Jerry can)

I redid all the return lines from injector to injector. And every line in the engine compartment.

Installed a new lift pump.

I have pressure at the shrader valve at the fuel filter.

I have checked compression on all cylinders and it checks out at 300psi +- 10.

Did the injection pump fail?

Neat tid bit. Also while driving home after buying it the dummy temp dash guage read A to L, almost overheating the whole drive home. I installed a new mechanic block guage the next day and the truck was never overheating just saying it was getting close on the dash. However, the previous owner installed a new radiator and thermostat. Was this truck overheated?

Compression test came back normal from what i understand, therefore I assume the injection pump went out. Any suggestions?

Thanks

 

what you can check is if the Housing Pressure Regulator is clogged... is it possible you had water in the fuel ?
IF there was water in the pump then a number of Items could be sticking (Internal Pump Parts)

it sounds like a Pump rebuild is in order .... easy enough for most Diesel fuel system shops to test the pump on the bench.

 

I see no mention of changing the fuel filter.
If there is water, it should lay in the bottom of the filter, but if a lot
then yeah it could pass into the IP and Injectors.. Not a good thing for sure.


Charlie

 

Make sure you have good, clean 12V at the Fuel Shutoff Solenoid on the front of the injection pump. There shouldn't be any accessories tapped into the connector.

 

I show 11.12 volts at the seliniod with the key turned to on. With truck turning over it drops to 0 then starts to climb to 8-9 volts before it dies. There are two wires going into the seliniod connection at the front both are red and it all looks like factory wiring harnesses. No extra wires attached. Why only 11.12 volta at the IP seliniod? My batteries are showing only 12.25 volts. Is this the problem?

UPDATE:
The truck ran for about 10 seconds today and then died. Ran again for a 7 seconds or so then died. It sounds great when its running then shuts off and back to same old symptoms. Now wont start at all.
I dropped the exhaust at the muffler and was stoked thinking I found the problem for the first 10 seconds it ran. Its not the muffler. I'm thinking its the metering valve in the injection pump. Any other thoughts before I pull the pump cover?

 

UPDATE

I checked the filter housing by removing the main line off the back heading towards the IP. It shoots plenty of fuel when cranking from there so I dont think thats it.

I dropped exhaust

I have put two new fuel filters in. Minor gunk in the first new filter put on.

 

I show 11.12 volts at the seliniod with the key turned to on. With truck turning over it drops to 0 then starts to climb to 8-9 volts before it dies. There are two wires going into the seliniod connection at the front both are red and it all looks like factory wiring harnesses. No extra wires attached. Why only 11.12 volta at the IP seliniod? My batteries are showing only 12.25 volts. Is this the problem?

OK this is not Normal... one side of the Fuel Shutoff Solenoid goes to Ground the other side gets 12 V when the Ignition switch is in Run or start position and should be same Voltage as the Battery.

as a Test you could jump the Hot side of the fuel shutoff solenoid direct to the Battery.
BUT I don't think this is gonna fix your issues.

EDIT: I think the batteries are weak too....

 

Your batteries could be drained from cranking the engine. You can always remove them and have them tested at an auto parts store.

 

Batteries are brand new after I bought the truck. Definitely low voltage though from all the starting attempts. I'll recharge today.

 

These symptoms You describe remind me of when I was running watery off road diesel. I replaced both fuel tanks, did 38 gallon rear tank swap, replaced both fuel senders with T-Rex senders and modified rear senders plastic barrel float arm with jb weld and an aluminum brazing rod to make it 6" longer to accurately read fuel level and put 8 new injectors with hardware and has been running pretty good since I switched to the green diesel. Also I bought Odyssey batteries and I can tell Ya dems sum bad girls!

 

Picture of my IP with the cover removed. See all the black particles in the top right of the pump res? They are rubber and i pulled several larger chunks out. What the hell is that? Is it worth even putting back togrther or did i just find that my IP is bad, clogged with rubber from somewhere. Also there were a lot of metal particles floating around and attached to the magnetic metal compentents.

 

Top left in this picture. Lots of crap!

 

Like I said..... Kits are cheap enough, but it ain't a job for everyone....

must be one of the old style pumps with the rubber Flex ring

 

Yup that's what it is. You can try picking all the pieces out and carefully reassembling the top without jamming the metering valve (or it will run away) and then cleaning the housing regulator fitting in the top cover (it's the black fitting) it has a glass ball in there and a spring.

At this point that ip has to be way past it's prime. I would just replace.

 

those flex rings only lasted about 10 years or so no matter the use of the Pump. I've done my share of em in the past.
probably much shorter life with today's fuel.

they make a complete seal kit with the solid cage replacement now for like 60 bux,

but for most folks, yes just replace the IP .... put it back together as you will need it for a Core.