# Needing help with bleeding air from CAV pump & System



## Okie72 (Mar 31, 2016)

I have a 1973 Ford 3000 that i'm changing out the seals on a CAV injector pump and I was wondering if anyone has a procedure on bleeding out the air in the system when I'm done.

Thanks


----------



## sixbales (May 18, 2011)

Howdy Okie,

This is a procedure originally posted by Jerry/MT on the YT Forum. I’ve added a few things, but it’s the best detailed bleeding procedure that I’ve seen.

My tractor can be a PITA to get started if I run it out of fuel, or if the filter gets plugged.

How long has it been since your fuel filter was changed?? Might be a good time to change it.
*____*

Start at the fuel outlet of the tank (inlet to the filter). Shut the tank valve, remove the line at the filter inlet and holding a suitable container to catch the diesel fuel, open the valve. You should have a CONTINUOUS rush/flow of fuel out of the line. If it dribbles or is intermittent, check the fuel cap for a blockage of the fuel vent or the strainer upstream of the valve for clogging. The strainer/screen is attached to the shut-off valve, and is positioned up inside the tank. You will have to drain the tank and pull the valve to clean the screen.

If you have good fuel flow at that point, reconnect the line and open the bleeder screw at the top of the filter. Turn on the tank valve and wait till you have a steady flow of fuel with no bubbles at the top of the filter, then close the bleeder screw.

Your pump may have a bleeder screw. If so, open that and crank engine until fuel streams out with no bubbles, then close it. Otherwise loosen the inlet connection at the pump and purge air at that point.

Go back and make sure ALL the fittngs in the fuel delivery system are tight so they cannot suck air.

Make sure the battery is fully charged. Loosen the fuel fittings at the injectors, either one at a time or all at once. Crank the engine till you see all fuel at the injector fittings and then tighten the fittings. If you do indvidual fittings, the engine will usually start before you get to the last fitting.

Alternatively, you can "tow-start" it to save wear and tear on your starter. Leave the injector lines cracked open at the injectors at first to purge the lines. Then tighten them up and she should start.

Your injection pump puts out a very small amount of fuel (high pressure/low volume). BE PATIENT. If the lines are totally empty, it takes a lot of cranking to fill them up.


----------



## sixbales (May 18, 2011)

Hey Okie,

Attached are two CAV manuals, in case you need some guidance.


----------



## Okie72 (Mar 31, 2016)

Thanks Again for taking the time to Help again!!!


----------



## Hacke (Feb 22, 2011)

Here is a link to the Operator's Handbook, in a pdf file:
www.fordson.se/1000.pdf


----------

