I swapped a zf 5-speed into my Bronco2. I'm having issues engaging the clutch. I'm runnin a stock B2 master with a 89 f-250 slave, I don't know if I have air in the system or if my master doesn't have enough throw for the slave. I have heard the B2/ranger master is hard to get all the air out of, I had it pressure bled but it only helped a little. Is anyone else running this setup, and what were your results?

i would think the master is a little small. what is the bore and stroke ? let me know and ill crawl under my parts truck and look at the master on it

I'm not sure what the bore and stroke are. I got the master out of the f-250 and it looks pretty close in size, but who knows whats inside.

I have a couple trick which help to some degree, but are not a substitute for new replacement:
1) take an extra master cap, drill and tap for an 1/8" MPT hose adapter, install adapter and use a Mity-Vac pump to reverse bleed the slave/master. It usually works fairly well.

2) remove the slave from the bell, careful not to lose the plastic endcap on the rod, and then completely cycle the plunger 4 or 5 times; seems to buy a few months on the Superduty slaves.

Make sure to check for even the smallest amount of wear or flex in the pedal linkage.

I found the slave hard to bleed as others have. I have only done it twice, but both times I had to have my helper slam the pedal in hard a few times!

My friend had the same problem with his truck. After he switched to the right master it solved his problem so I would start there

Jimbo, I had the system pressure bled, would reverse bleeding (suction) work better? As far as my slave cyl. goes it's an internal, so no removing it.

Ianretsr, My friend had the same problem with his truck. After he switched to the right master it solved his problem so I would start there
Could you elaborate on this a little more?

My whole system is brand new; pedal rod, master, line and slave. Clutch is new and trans has a fresh rebuild. I even tried unbolting the master so the line was the highest point while pressure bleeding. It seems to get better after sitting a few days but after hitting the pedal a few times it goes back to not being able to engage the clutch. HELP! I really wanna start driving this thing again.

it sound like there is air in there, due to it getting worse the more you use it ( aka airating the fluid )


did you bench bleed the master before installing it ?

if it was like my friends your should be having problems shifting or even putting it in gear from neutral. His went to the extent that he would have to turn the motor off to get it into reverse. The problem he had was that used used the stock master on his f150 with the zf and slave from my f350. His bore size was smaller then what I had on my master and it caused it to not fully release. After replacing the trans and two clutches he finally put in the right master and all the problems went away.
If you think you still have air in the system you might want to try collasping the slave a few times by hand.

Just replaced the master and slave on my F350. Just about lost my mind.
After 3 days of fawking around I finally bench bled the master and all went well after that.
Take off the line at the master, take a fitting that fits inside the master and has hose barbs at the other end. Get some clear fuel line or similar and connect it to the fitting. Since my fitting didnt fit tightly in the master I wrapped teflon tape around it until I could just jam it in there. Take off the fill cover and the rubber cup thing. Fill the master 3/4, hang the other and of the fuel line into the master, below the fluid level and have someone pump the pedal a few times.... real slowly or you'll wear the fluid.
You'll see after a few pumps that there's no more air bubbling up.
Fill the master reconnectthe line to the slave and bleed at he slave 2 - 3 times... done.

What year B2 master do you have? You need a master with a 7/8" bore to power the 89 zf slave. If you get the slave for an 88 B2 it should work anything before 88 was a 3/4" bore. I just ran into a similar problem with my f-150 when swapping in a t-18. The master was not big enough to power the 89 slave. As soon as I matched the parts it worked great. Napa's website has all the bore sizes listed.

if it was like my friends your should be having problems shifting or even putting it in gear from neutral. His went to the extent that he would have to turn the motor off to get it into reverse.

This is exactly the issue I'm having.

I have an 87 B2 I guess I should try a master for a 88. I'm gonna pick up the master on saturday. Thanks, thejon2524, I'll let you guys know how it works out.

Did you get everything working?