Installed an air blead and pressure port on my P7100

[T. Baker]

I wanted an air bleed and a pressure port on my pump. There is a plug in the very front of the pump with a 10mm allen hex hole in it. Bosch did not want it removed so they put some type of locking stuff on it. It smacked it with the impact driver with no luck. Then I did somthing really dangerous!!!!! I made sure the pump was full of fuel and had no air in it. No air no fire. Then I proceded to heat that plug with a plumbers torch very carfully!!! Then I imeadiatly used my half inch impact wrench and out it came. I went to the hydrolics place down the street and they gave me a 18mm X 1. 5mm pich fitting to 1/4" pipe. It was too big so I put it in the lathe and made it a little smaller in diameter and I put it in with a "T" fitting with a bleader screw on top and a plug for a pressure gage later. I can now blead all the air out of the fuel pump easily with the hand primer and don't have to crank on the starter motor!! The best part is I am still alive and the pump did not turn into a hand granade

Treven. Oo.

 

[Extreme1]

I love a good mod that involves fire!

 

[CumminsPower98]

The P7100 would be the "Holy Hand Granade"

That's brave, I think I would have a real hard time taking fire to my loaded fuel pump.

 

[Steve Campbell]

T.Baker

If that "plug" was at the top of a lift pump pressurized cavity before the P7100 takes the fuel up to injection pressure, a small orifice or pressure regulator hooked into the return fuel line should gain you most of the benefits of the fuel preperator ($1000) system.

 

[T. Baker]

Wow $1000!? What is a fuel preprator and who is selling it? Sound like a major rip off!! Thats where the plug is and I was thinking that if I do have any trouble with that return line pressure valve I could just plug that hole with the plug I took out and put my own adjustable pressure valve in at my pipe plug and run the return line there.

Treven.

 

['956Wheel]

Why?

Why bother? Theres plenty of places to put a pressure gauge and a bleeder. I'm glad we won't be seeing you on "Real TV"!



Mike

 

[T. Baker]

Mike there is a bleeder on top of the fuel filter but it only bleeds the air out of the filter. If you want to bleed the air out of the fuel pump it needs to be right there at the front. What I did makes for easy hand bleading without having to blead through the presure relief valve. You can always use the starter as well but I don't like to make my starter crank more than it would in a whole month and get smoking hot to get the air out. Also the presure port for the gauge reads what is actually at the plungers.

 

['956Wheel]

T. Baker,



We have a member on board who was/is making banjo bolts with an 1/8" NPT tapped into it that replaces the inlet one on the P7100. They were just a few bucks and one he!! of a lot safer and easier than playing with fire. If you need it chances are it is here, some is junk, IMO, but many are real good ideas.



Mike



Also, those banjo bolts were made with larger holes for better and more flow.

 

[T. Baker]

Bleeding at the inlet dosen't get the air out of the pump.

 

[illflem]

I've always thought it odd that the P7100 doesn't have a bleed on it. Good move, hope you don't need it much.

 

['956Wheel]

I guess I must be an old fart or something. First, I have never had any problem firing up the Cummins after pulling DV's or injectors, second you bleed the entire system at the injectors upon start-up anyway.



I just do not see the necessity of such a extreme move for a "gain" that is so little. I do however look forward to your post on pressure gauge installation.



Fear? Not me! I have welded gas tanks, tightened control valve bonnets on steam turbines... . hot.



I am glad you did not BBQ yourself!



Mike



Bill, 5000 posts! I got some posting to do. Hows MT?

 

[LarryB]

I guess I'm under the mistaken impression that the overflow valve/return line serves this purpose. It regulates pressure and returns air to the tank. That's why it is at the top of the pump.



Shows how much I know.

 

[Todd T]

considering the ease of starting one of these trucks after having fuel lines off or anything else along those lines. i dont think the risk and time you took is worth it to me



give the primer a few shots and it fires right up, every time.

 

[T. Baker]

Well maybe I didn't have to do it but on other trucks there have been times when I had to bleed on the side of the road with trucks and cars passing me by at 60 to 80 MPH and the faster you can get going the better. You can get air in the fuel when you least expect it and loose prime. This engine is new to me but I just felt like I wanted a really easy way to get the air out.

Mike;bleeding at the injectors requires wrenches and cranking the starter motor wich I don't like.

Larry; pumping past the return valve requires at least 20 psi to overcome the spring in that valve wich is really hard on your finger as you try to lean over to get to the primer button wich is in a bad spot in the firs place. Other trucks I have had have a hand primer mounted in an easy to reach spot with a nice handle that dosent hurt.

YOU CAN HAVE FUEL PROBLEMS WHEN YOU LEAST EXPECT THEM!

I also plan on having an electric primer back up pump.

 

['956Wheel]

Its a free country, sort of, and your truck. Halon works well!:{



Mike

 

[illflem]

I don't think it's a waste to have a bleed on the pump as long as it's easy to do. Most all my tractors have one there, never use the bleed on the filter, some don't even have one there. Have to wonder why the plug was so durn hard to get out though.

 

[Todd T]

T Baker, i didnt mean to ruffle your feathers. its great that you shared the idea with us, and it is a good idea. I guess what i meant, was it isnt worth it to me. i dont travel alot with the truck just daily commute to work. I have always heard of guys burning starters up and that sort of thing to restart after a failure or working on it. I have worked on tractors that are a real PITA to get going agian but these trucks are not in that catagory. they are pretty rugged in that aspect.