M818 sucking air

[KsM715]

While working to get the M818 up and running after sitting over last winter and summer I've come across a leaky fitting. While operating the primer pump I noticed this fitting dripping fuel. Could this fitting be sucking air into the system? Its not before the IP so I dont think so but Im not a diesel mech. I took it apart and noticed the the plastic line had been whittled down to get the brass ferrule to fit over it.

Once I got the truck primed and running it seems to run fine. Throttle response is quik but takes a second or 2 to drop down to idle and will drop pretty low, if its still cold it will die but if its warm it will drop and return with out stalling.

 

[doghead]

It could suck air there, if one of the check-valves in the pump are sticking open.

Does the hand pump feel like it operates quickly and efficiently?

I ended up replacing the lines on my hand pump, to get rid of a very similar issue.

I had replaced the orings and cleaned the check valves first, without curing the issues.

If you clean the pump, pull it from the dash and do it in a cake pan, so you do lot loose the ball and springs under each of the screws. And there is also a needle valve that needs to move freely(inside it).

 

[KsM715]

When the system is primed, the pump handle is very hard to operate. I can see the fitting when the hood is up and I'm pumping it and watch it drip. (when I'm pushing the handle in I can see it push the fuel out pretty good, almost a steady stream) when the system has lost prime the handle pumps really really easily and smooth.

 

[doghead]

Sounds like a sticking valve in the pump, to me.


I use carb and choke cleaner and Q tips.

Notice that the needle valve is spring loaded(on the end of the pump shaft)

 

[KsM715]

Thanks, guess I'll ad this to the list of "things to do" before it gets listed.

 

[doghead]

It's really only a 30 minute task.