Dear ride,

You replaced the OF valve with one that was different and it runs poorly. When you reinstall the original it runs great. Does it occur to anyone that the replacement is the wrong part for your engine?

Edit: I have a new thought after reading dieselhawg's post: The banjo bolt at the lower rear of the pump is the fuel supply and will look like you described with four holes. If you installed your new OFV there it will run badly. The true OFV location is the top front of the IP towards the block. Where did you install the OFV?

 

If it has no ball and spring your fp will be very low, you'd get smoke, low power and poor fuel ecomomy.

 

Good call RARE1, how many read that and missed it,, including me!

 

Wow... I'll have to go back and look but tried using the figures from these photos to find the right location:

not labeled on this page: http://dodgeram.org/tech/dsl/Facts/12Ve_locations-l.gif

http://dodgeram.org/tech/dsl/trouble...p.htm#Overflow

http://dodgeram.info/tsb/1996/14-07-96.htm

The photos are closeup so it's possible I still had the wrong piece... I'll go back and look after work and let ya'll know! Thanks for the heads up on that!
Dave

 

Oil fill cap at lower left

 

Rare1, you hit the nail on the head. I focused on the first banjo bolt I saw and got the wrong one. Found the right one. Will try to swap out the valves later this week when work slows. Thanks for the insight!

Dave

 

Beware! on some engines the OF valve hits the manifold before coming out.
DO NOT bend the return line to get it out, you'll have a heck of a time lining it back up again. Instead of bending file or grind the cutout on the manifold so it comes out easily.

 

A little clarfication on what I was saying in this post.

On some 94 and a few 95 the overflow valve was a one piece unit and did not have the bolt on the top for removing just the spring itself. I thought this is what was being referred to as the "hollow bolt"

Good catch "Rare1" I guess some of us just assumed he was replacing the correct banjo.

 

Nope. Had the wrong one, Rhino. Feel a bit silly on that one... Thanks again for all the help! Saved me some trouble, that's for certain. And thanks for the helpful hint, Infidel!!
Dave

 

After all this guessing, you have a air leak at the OF valve. It is not tight enough. Be sure the 2 little gaskets are still on either of the valve.

..PT..

 

Yup, already had to fish one out twice (from the initial wrong emplacement). Easy to have one slip out!

 

What should the pressure be and how do you check it?

 

FP at idle should be 20-26 psi and not exceed 35 at high idle.
Best way to check the fp is to drill and tap a 1/8" port into the top of the injection pump inlet banjo bolt after removing it. You can then attach a hose (grease gun hose works good) with a gauge. This is what Cummins uses. Plug the port when you are done. Another option is to buy an adaptor from TST that replaces the fuel filter bleed screw and converts it to 1/8". Available here http://www.tstproducts.com/index.asp...PROD&ProdID=62

For many people just replacing the overflow valve every 75k may be a better option.
Best price here.
Precision Diesel Injection and Turbo Inc.
Marty Tompkins
888-734-7349
$27 + $5 shipping and handling.

 

Overflow valve replaced. Finally... Seems to run pretty close to the same. We'll see how things go.
Dave

 

I just replaced my overflow valve with one I got from Marty. The new one will hold pressure for about 10 mins after engine is shut down before it drops to 0. Is this OK?

I noticed with the new valve the needle bounces all over the place. Old one didn't do it. I am using TST's snubber. Tough to get a reading at idle. I think it's around 20-25 psi @ idle. Old one was 17 psi.

The old OFV was the 2 piece model. I took it apart. Spring measured .450. Shims were .075.

Also What are your guy's opinion on my pressure gauge? It's a Summit liquid filled 1.5" 0-35 psi mounted to TST's snubber, in the air bleed hole on top of the filter head. Is TST's adapter going to hold up, or will it break?