what does the crew do on the top right of the first pic

 

Great post, I found this post via google.

I'm looking for some info on the electronically controlled mechanical injection pump, VE Covec-F, but would not post here since it's a Dodge thread

My tread: https://www.dieselbombers.com/passen...pump-work.html

 

Yes, MEEE. Firstly thanks goes to Bobby.. That was one hell of a post. I now know how my pump works. I have had hell with mine, but okay now. Also as his post say; it will help me greatly in thefuture, and anyone else that read it. I just had to join the forum hope to find lots more like this. Cheers guys. Pete.

 

Hello out there-

new to the forum... got a head scratcher here i cant seem to figure out, hoping someone here can give me some insight.

Have a 93 ford medium duty (f600) with a turbo/ intercooled 5.9. Im having some issues with the injection pump (its a ve rotary, not an inline).

Problem started a couple days ago... the truck seemed to run out of fuel. It however was NOT out of fuel. My first chck was the lift pump, it was working just fine and putting out a healthy 7psi.

Second, i changed the fuel filter- just on principle, it had been a little while.

Next i primed the fuel system, and bled the injectors. It fired up without much trouble and will stay running for the most part.

However- its missing consistantly on one cylender (#6 right at the back).

After some searching, i have found the the injection pump is not suplying any fuel to this cylender- or at least, nearly none- and not enough to fire the injector.

When the teuck is running, i can crack the lines on each of the other injectors and get a nice spray of diesel, but when i crack #6 i get nearly nothing.

I have also removed the line from the back of the pump itself and also get nothing.

The other cylenders seem to be running normaly, so im inclined to thank that the pump is still ok for the most part... perhaps the delivery valve for #6 is not opening properly?

I know there are lots of guys on this forum smarter than me- lets hear your thoughts.

This is a work truck, need to get it going asap!

Thx in advance for your replies- Andy

 

If you value your pump, and don't want a big bill for smashed things, get the pump seen to straight away. I'm only an owner who came here looking for ideas on a problem that I have, but if something is adrift inside...oh the pain.

 

Similar post a month back, his would only stay running with #6 cracked.
I suspect air was getting into the system and crack #6 bled it off, without cracking #6 the air built up and got into the other lines. #6 is at the top of the pump. As usual if he fixed it he did not give any feed back.
Common deal here, never feedback when the issue is resolved.

By what you are saying you have some fuel but not a lot at #6.
Either air or a blockage

 

Yes- thats exactally whats happening to mine.

I have found that i can keep it running nearly forever with #6 cracked. Once i tighten it back down it seems to runo allright for a while, but once i rev the motor it stops firing and eventually cavitates the pump.

Im a little bit puzzled- if it were a blockage in the pump, or a delivery valve issue, i could understand why the injector quits firing.... but that dosent explain the air does it (or am i missing somthing?).

If it is an air intrusion in the system... would that allways affect #6 first? Wouldnt it airlock all of the injectors? Thats what usually happens if you simply run out of fuel.

 

A good idea is to replace fuel hose with clear vinyl tubing in low pressure parts of the system, this will tell you a lot, as it has for me. Doesn't need to be reinforced. In a rotary VE pump I cant imagine how could air could into only one injector line but who knows.

 

Neither can i. Thats why im so confused.

an air intrusion would occour only between the tank and the lift pump, correct?


I do have a theory (but im not sure it really makes any sense...) is it possible that, if somthing in the pump is preventing fuel delivery to the #6 injector- the injector is allowing compression air (from cylender #6) back through the line and forcing its way into the pump, causing it to cavitate?

Im just spitballing here...

 

I'm fairly sure that the air getting into my IP was coming from a split in a perished section of rubber tube in the injector overflow drain line. I can blame the injection guy for this as when he overhauled my injectors he didn't use the correct tube - the manufacture's tube is z-shaped, my injector guy used bent-up straight fuel tube. Because of the way Isuzu set the fuel system up, injector overflow moves through a three-way banjo junction BACK to the IP inlet, and not straight back to the tank. So it's NOT true that air can only get in between your lift pump (which in the case of the Bosch VE is an in-built vane pump) and your tank. Incidentally I found that very few people (including the guy who overhauled my IP almost a year ago) understand how the CSD (Cold Start Device) which is an integral part of the fuel setup in this truck actually works. It's the opposite to how people imagine it works.