Zf6 swap hydraulic problems
Thread Starter
Instructor
Joined: Apr 2012
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Zf6 swap hydraulic problems
So I put a zf6 in my 85 everything was put back together no problem ,but I'm using the 4+3 master with the zf6 slave and the rod seems to be hyper extending I've heard of a "spacer" but i dont have one. does anyone know if that's my problem?
Safety Car
Joined: Feb 2000
Posts: 4,564
Likes: 110
From: Austin Texas
The SYSTEM is designed to work together...throw out a MAJOR part of the system and replace it (like with a 4+3 master) and it just isn't gonna work. Period.
You have 2 choices:
1) Install ALL of the correct equipment so it works, or
2) Throw the baby out with the bath water...
At this stage, you are too far along to rip it all back out.
The 4+3 master was DESIGNED to push more fluid as the push-style clutches needed more throw to disengage.
Your only other choice is to put a pedal stop in to prevent it from going too far.
It's your car...do with it what you like.
Suckin' gas, haulin' ass.
Joined: Apr 2010
Posts: 1,100
Likes: 8
From: Newport News Virginia
You can shorten the rod that goes through the firewall into the master. The pedal will sit a bit lower at the top, but it would stop hyperextending the slave. Either that or put a stop on the clutch pedal so that it hits the firewall. Those are the two cheapest options.
Le Mans Master
Joined: Oct 2007
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From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
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St. Jude Donor '09-'10-'11
Sounds like a pedal stop would be easiest at this point. With the car jacked up and in gear, push the clutch pedal just until the rear tires can spin freely (may require two people), go no more than 1/2" of pedal travel beyond that point, and that is how far your pedal should go. Make a stop to keep the pedal there.
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Suckin' gas, haulin' ass.
Joined: Apr 2010
Posts: 1,100
Likes: 8
From: Newport News Virginia
Just push the clutch in as Kubs said and measure the distance from the pedal to the firewall. You are probably going to have to weld something (like a bolt) on the pedal the correct space from the firewall.
Le Mans Master
Joined: Oct 2007
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From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
You could go a couple different ways. The easiest would be to just bolt a piece of wood to the firewall for the pedal arm to hit. Mount it close to the pivot point.
Melting Slicks
Joined: Apr 2007
Posts: 2,616
Likes: 111
I just need to be the devil's advocate here for a second........You went through the trouble of the ZF conversion in a 1985 Corvette.....but you are not willing to swap out the old master cylinder for the proper ZF master cylinder to properly put things in order?? I am assuming if you could afford to get that far, you can afford a master cylinder???
I guess I'm missing something here.......to me its like buying a new set of tires and having them mounted but not willing to spring for the balancing????
Help me out here??
I guess I'm missing something here.......to me its like buying a new set of tires and having them mounted but not willing to spring for the balancing????
Help me out here??
Melting Slicks
Joined: Apr 2007
Posts: 2,616
Likes: 111
I see,
well, personally installing a wood block on the floor board of my Vette to stop the clutch travel is a little bit........well, I'll stop here and bite my tongue.........
have fun my young Vette owner brother......
well, personally installing a wood block on the floor board of my Vette to stop the clutch travel is a little bit........well, I'll stop here and bite my tongue.........
have fun my young Vette owner brother......
Le Mans Master
Joined: Dec 2002
Posts: 5,270
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From: Seattle Area WA
Don't build it out of wood, but don't feel bad about the pedal stop. They are extremely common and when you rewrite the book sometimes necessary. Also, some racers (myself included) like the pedal stop as it shortens clutch throw and helps with faster shifts. To each their own. Kudos to you for the ambitious project at 17.
Anyway, quick and easy you can take some aluminum strap and 4 bolts and clamp the strap to the clutch pedal with it bent in a 90 at the base so it has good and well distributed contact with the floor. Might be worth a shot.
Anyway, quick and easy you can take some aluminum strap and 4 bolts and clamp the strap to the clutch pedal with it bent in a 90 at the base so it has good and well distributed contact with the floor. Might be worth a shot.
Thread Starter
Instructor
Joined: Apr 2012
Posts: 115
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Thanks guys I am fiddling with the new clutch master cylinder as I type this looks like it's straight forward and simple compared to the rest of the build. hopefully tonight I will have my vett back on the road where it belongs 