F-800 8.3L No power!

[socks]

I have a 1998 F-800 with an 8.3L cummins engine(3500hrs) that is not making power on the highway. It will idle fine ,is hard to start --- I have changed the main fuel filter, I cleaned the primary filter screen( which was very dirty with big chunks of crud )! Is there any other screens that can be cleaned, has anyone else had this type of problem.

 

[Red Bank]

We were having that problem two years ago on our 8.3L Cummins in a 1999 Freightliner, we took it to Cummins and they replaced the fuel pump, are you getting a Check Engine light that is coming on? You may be able to pull the codes and call Cummins to decipher them for you?

 

[socks]

No the check engine light is not coming on.

 

[Red Bank]

Have you checked the fuel lines back to the tank? And have you checked the tank? I had an issue with my 955 loader-lost fuel pressure- removed the line from the tank and there was a bug that was trapped in the line and the crud had built around it and stopped the fuel flow. I know your problem is on a truck but anything is possible. The other advice I have is to call the Cummins dealer. That fuel pump set up on the 8.3l is weird to me and I am not completely sure how it works. It might still be the culprit without throwing the check engine light on?

 

[Goose]

Remove the inlet fitting at the transfer pump item # 15 and check the screen for contamination. Also check the fuel shutoff solenoid and make sure it is going full travel and not keeping the fuel partly shutoff.

 

[Aliate]

I had a similar problem in my GMC T7500 with a cat 3126 and it was water in the fuel. Driving around the streets would be fine but then when I went on the highway going up a slight incline the motor would shutter and the truck would slow to like 25mph. Even when I drained the water from the filter it didnt stop until I completely replaced the filter.

 

[socks]

Sorry for the slow reply; ended up draining the tank, putting fresh fuel in it. Then took apart primary filter bowl and screen again, with a mirror found more crud in the input nozzle cleaned it, blew out some lines,put everything back together again and still hard to start and no power.
With lots of last minute jobs on the go and winter knocking on the door I decided to take the truck into a highly recomended dealer. The dealer just told me today that I have 2 problems, 1) my starter is drawing way to much current which will affect my different solenoids. 2) That my fuel solenoid is falling apart internally. Throw in a block heater install, to a nice sum of $1600.00

 

[rino]

Socks: I know that it is repair shock, but these were problems that are hard to correctly diagnose in the home shop! If this fixes the problems wasn't worth it? After it could have been worse than $1600.00! You might have had to replace that fuel pump! Now you know your truck is in running order! You could even be still throwing money at the problem! Making unecessary repairs!

 

[socks]

You are dead on Rino it was money well spent, they even gave me tips on the trouble spots for that engineand some things to watch for, so I consider it worthwhile

 

[truckboy]

the cheapest thing to do would be 2 put a chip in it but if u really wanna invest in something put a supercharger in it

 

[mikesheldon]

the answer is the fuel filter.check it out