Cummins 4BT & Diesel Conversions Forums banner

1 - 6 of 6 Posts

·
Registered
Joined
·
173 Posts
Discussion Starter #1
So I start my diesel and it starts right up and runs rough sounds like it is missing a little. While its running I bleed the injectors and none of them have air accept for one the 3 cylinder i bleed all the air out and the diesel runs really well for a few seconds and then it starts back to shaking could that be a bad injector or what?

:) Halfbreed:)
 

·
Registered
Joined
·
696 Posts
If the air keeps returning then it sounds like you have a leak on the suck side of the lift pump. BTW is your lift pump OK? as in you know it works? If your lift pump is out the IP will suck its own fuel. and then the air leak could be anywhere from the tank to the IP. I had an air leak on mine when I first got it running and once it goes into the metal lines its difficult to trace it. upto the lift pump I have clear nylon lines so can easily see air in them.

Gaza
 

·
Registered
Joined
·
173 Posts
Discussion Starter #3
If the air keeps returning then it sounds like you have a leak on the suck side of the lift pump. BTW is your lift pump OK? as in you know it works? If your lift pump is out the IP will suck its own fuel. and then the air leak could be anywhere from the tank to the IP. I had an air leak on mine when I first got it running and once it goes into the metal lines its difficult to trace it. upto the lift pump I have clear nylon lines so can easily see air in them.

Gaza

I dont know if my pump is ok the diesel seems to be starting fine and everything runs good except the one injector i took it out and inspected it everything seems to be ok? after i start it back up and bleed it it runs good until I rev it then starts to get air in the lines. I am going to replace the lift pump i just ordered it. But I think that it is a bad injector cause if their was air in the lines wouldnt taht effect all the lines instead of just one?
 

·
Registered
Joined
·
220 Posts
So I start my diesel and it starts right up and runs rough sounds like it is missing a little. While its running I bleed the injectors and none of them have air accept for one the 3 cylinder i bleed all the air out and the diesel runs really well for a few seconds and then it starts back to shaking could that be a bad injector or what?

:) Halfbreed:)
Sounds like a bad injector. Compressed air from the cylinder can be forced back through the injector if the injector is "hanging". If you want to verify this, switch the injector to another cylinder, and see if the problem follows the injector. Also the lift pump will not cause air in the line of one specific injector.

Bob B.
 

·
Registered
Joined
·
173 Posts
Discussion Starter #5
Sounds like a bad injector. Compressed air from the cylinder can be forced back through the injector if the injector is "hanging". If you want to verify this, switch the injector to another cylinder, and see if the problem follows the injector. Also the lift pump will not cause air in the line of one specific injector.

Bob B.

i will try that thanks
 

·
Registered
Joined
·
696 Posts
Sounds like a bad injector. Compressed air from the cylinder can be forced back through the injector if the injector is "hanging". If you want to verify this, switch the injector to another cylinder, and see if the problem follows the injector. Also the lift pump will not cause air in the line of one specific injector.

Bob B.
Excellent, never would have thought of this.

Gaza
 
1 - 6 of 6 Posts
Top