1985 F350 6.9l 4 speed

Well after going through all the trials and tribulations with trying to figure out the best way to bleed this clutch system, I finally figured out a way to squeeze just about all the air out so none if very little bleed is needed.

This will work if you are replacing just the master, slave, line or any combination of the above.

I was replacing the slave cylinder so it did come with a new strap holding the rod in. I have, in the past taken a cutoff tool and cut just a small groove in the ball end of the rod to run a string through and hold the rod in if not replacing with a new slave cylinder. Just a very small groove mind you. Just makes installation of the slave so much easier and reduces chances of air getting trapped.

If installing new master cylinder go ahead and get it mounted and clutch rod adjusted close to where old one was set. I'm not sure about how much free play is needed when finished so I won't comment on that. Go ahead and fill reservoir and replace rubber and cap. Now hook the line up to the master cylinder.Install new pin that holds line in. Get a small container with about 3 inches of brake fluid in it and stick the other end of the clutch line in container. Now have someone pump the clutch and watch the air come out and the fluid go in. Only took about 12 or 15 pumps until all the air was out of the Master cylinder and line. Now cap off the line and feed it down through to where it will hook up to the slave cylinder. Recheck fluid level in master cylinder and top off if needed.

Now take new slave cylinder or (grooved out old one with rod tied back in as tight as you can get it) and start filling the inlet hole with fluid and rotating and shaking to get all air out as you pour fluid in. Get under truck and hook up line to inlet. Helps to squeeze one end of the pin shut just a little to help it set in the hole while you drive it in. Mount slave cynder.

If everything went good, you should immediately be able to feel almost full pressure from clutch pedal. ( Don't forget to cut string if you used the groove method ) And by the way, I am not endorsing or encouraging you to cut a groove in the slave cylinder rod ball end. But it is the only reliable way I have found to hold that rod in when putting a used slave cylinder back in mounting slot. It also helps keep air out to have it fully bottomed out because I have fought with trying to get one in that wasn't held back in place and as you know,,,, it aint fun.

I know this isn't the factory way or the normal way of doing this but I have fought, cussed, screamed and threatened to push truck over hill in the past. Bleeding would not seem to work like it should and I know this has frustrated a lot of people. So maybe if just one person tries it and it helps then maybe I have contributed back some to all the people on this forum that have helped me in the past.

Peace

 

That's a quick way to get most of the air out of the system so the clutch will start working. But like you said you will feel "almost full pressure" even after your method. The final method to get ALL the air out is patience. As you drive it, over a period of time any air left will slowly work it's way backwards up the line and eventually make it into the reservoir of the system.

You do need to start somewhere though, the more air you get out initially, the less time it will take to allow the rest of the air to get out by itself.

 

Your method is actually pretty close to one that is in the Ford shop manual...
They just say fill the master and let it run out the line, fill the slave until it is full and then put them together.
Another Ford method, and one I have posted many times but noone ever seems to listen to which I use all the time is to fill the system, put everything in it's place, then get under the truck and push the clutch fork towards the front of the truck, compressing the slave cylinder until it bottoms. Do this 10-12 times and the clutch is bled, without fail.

 

You're right, I never tried that method. When I did it this way, from start to finish was 20 minutes. I didn't have to bleed and I was on the road. Clutch was as tight as new and I guess it may get tighter in the next couple of days. My buddy asked me if I want to try to bleed it and I said NO NO NO Stay away from that bleed screw !!!! Like I said hope it helps someone some day