I have a 98 12 valve D250 - I let fuel gel. Truck idles fine but no power 45mph max, replaced injector pump, mechanical fuel pump, complete sending unit in fuel tank, still nothing and it is hard to start.

 

Have you tried any additives? And how long did it sit? Why did the fuel gel? How cold is it where your at?

 

Maybe try something like this.
http://www.powerservice.com/aedf/

And storing your truck in a heated area overnight.

 

Pour in Diesel 911 drain and/or replace Fuel filter. Could just be water/ice.

 

Have you loosen the fuel lines to each injector and bleed out and fuel out of each injector? I just had this type of problem and I have a air lock on 2 of the 6 injector and it would not start. Got the air out and it works perfect.

 

in cold weather i use powerservice (but when it geled),i have put 2 new fuel filters still 45 mph.i have bled injectors 4 or 5 times.

 

How do you know it geled? What was the temp at the time? Make sure the shut-off solonoid is fully retracted. Make sure the throttle cable mount is not loose or broken.

 

i had got fuel with some water,the fuel filter was froze solid,it was 6 deg. that morning truck started and ideled fine then ran out of fuel.then nightmare began.

 

If I read your original post correctly, it says that you replaced the injection pump? If you had the injection pump off, is it possible that you have a pump timing issue?
Just so that we know what all you're dealing with, why did the injection pump get replaced? Tell us a bit more of the story and we'll try to help you put the pieces back together again.

 

wwoody,
Geling and water in the fuel are 2 different things. I'm w/12valve, check timing, and also make sure injection pump is getting boost pressure signal. Its been a while I don't remember if the boost pressure is a manual or electronic. If you are running anything other than heating oil, you should be fine at that temp.

 

Look for air leak into fuel supply line to pump.

 

i would like to kown more of lock-stitch welding on 53 block

 

So...it runs but speed max is 45MPH? Is that right? If other checks mentioned above fail keep these in mind:

Do you have gages? What kind of boost are you getting? Have you checked the overflow valve? Return lines OK? Are you getting fuel out of lift pump? Have you checked Fuel heater screen for blockage there? The fuel heater can get an air leak into fuel and cause problems.

Check the fuel lines at the fuel heater. Air can get into a bad rubber line even tho fuel is not coming out as I have heard. Can be hard to find a bad fuel line. You may need to replace all rubber lines. The rubber portion of supply and return are prone to failure on these trucks.

 

Use the search function up above, lots of reading.
Or start a new thread of your own about it. This thread is about a 12v that won't run.