mikep_95133

Hi all, Brand new to the forum. 30 years with Mopars. Very first Cummins. Very first post. I've read a couple dozen threads first, but find myself stuck nevertheless. So I cannot find how the control valve goes back together. In fact I don't see the 3 pieces in any blow up diagram. The little round split collar looks like it's suppose to grip the inside of the bore and hold the spring and the piston in place. They were loose when I pulled the control valve out of the VE pump. I think the order shown in the pic is correct. I removed the piston and collar with a magnet. Does anyone know if the order of the spring, piston, collar is correct? Even the piston is not symmetrical. So how does it go in? The whole reason for the tear down is that the governor shaft seal was leaking badly. It's o-ring was brittle and it split when I removed it. Thanks! Mike PS I just picked up this 1993 2wd flatbed ext cab 3/4 ton truck 2 weeks ago from a ranch quite a ways from here (San Jose, CA). Almost got it finished. Got a few hundred miles on it. Here's my blog. http://rotordesign.com/1993cummins/

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mikep_95133

The local Cummins parts house called a pump rebuilder and got me the answer. I described to the rebuilder on the phone what the parts looked like. He told me the tiny hole in the piston faces down into the bore where the control valve (pressure regulator) sits. The rebuilder says that guys that play with pump pressures have this happen more often. But it happens in stock pumps as well. The clip goes in only until it's flush with the bottom of the control valve. The top of the control valve can be pounded down with a drift and hammer to increase the pressure he said. Also he mentioned that if I did that the pump would have to be calibrated again. Now worries here, this old girl is staying stock. The pic shows the correct way this valve goes back together.

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mikep_95133

The first pic is the using the large channel locks to push in the clip.

The 2nd pic is the clip in flush as the pump shop recommended.

The 3rd pic is after I drove the clip inward more with a philips screwdriver. Shake the valve when you are done. It should keep rattling, but just barely. I could see that the gap between the piston and the clip was set up to have the clip pushed right up to the inside edge of the chamfer, but no more. I actually overshot a bit.

I am reporting all of this info on my blog (link fixed): http://www.rotordesign.com/1993cummins

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mikep_95133

Turns out that the valve is working fine. A 207 mile trip was almost 26 mpg at 65mph.