Hydramax Hydraulic Clutch issues - leaking

[TheDude]

Hey guys, I'm pretty sure I know what the answer is here, but wanted to see if I'm missing something. We converted my '72 Fastback from an auto to a T56 Magnum 6 speed. To operate the clutch, we went with a Hydramax hydraulic system from American Powertrain. 

It's never worked well since day one and the clutch has been VERY stiff since it was installed. But it worked enough and figured I'd circle back around to making it more drive-able once I get a few more things crossed off the list. 

The other day in the driveway I was taking a look at the linkage trying to see if I could do anything to make it a bit easier to use. Didn't change anything but just pumped it 4 times to see how it felt. Very stiff and not usable, maybe even worse than before. Then I noticed that the fluid reservoir was empty and there was a pool of fluid under the car. So yea it dumped all the fluid and all at once. If I put fluid back in, it doesn't go down, but the clutch doesn't work either. 

So I'm thinking the slave either over extended or just blew it's seals. Either way the trans comes off and likely needs to at least rebuild the slave. Does that sound about right? Really not wanting to have to go through all that again if I can avoid it, especially if it won't work better than before so hoping someone may see something I don't. American Powertrain has been sort of a pain to work with so wanted to check in here and see if anyone can offer any wisdom. 

Thanks

 

[73' mach 1]

Hey guys, I'm pretty sure I know what the answer is here, but wanted to see if I'm missing something. We converted my '72 Fastback from an auto to a T56 Magnum 6 speed. To operate the clutch, we went with a Hydramax hydraulic system from American Powertrain. 

It's never worked well since day one and the clutch has been VERY stiff since it was installed. But it worked enough and figured I'd circle back around to making it more drive-able once I get a few more things crossed off the list. 

The other day in the driveway I was taking a look at the linkage trying to see if I could do anything to make it a bit easier to use. Didn't change anything but just pumped it 4 times to see how it felt. Very stiff and not usable, maybe even worse than before. Then I noticed that the fluid reservoir was empty and there was a pool of fluid under the car. So yea it dumped all the fluid and all at once. If I put fluid back in, it doesn't go down, but the clutch doesn't work either. 

So I'm thinking the slave either over extended or just blew it's seals. Either way the trans comes off and likely needs to at least rebuild the slave. Does that sound about right? Really not wanting to have to go through all that again if I can avoid it, especially if it won't work better than before so hoping someone may see something I don't. American Powertrain has been sort of a pain to work with so wanted to check in here and see if anyone can offer any wisdom. 

Thanks

I don't have experience with this unit but others will chime in how have. I just want to add that I've heard a lot about those leaking and most seem to be due to over extending and blowing the seal.

I personally want to convert to hydraulic but stories like this always make me 2nd guess. I've been thinking about getting APT's linkage kit and ordering a Tilton bearing with whatever master cylinder needed to match up properly. I can also attest to APT's customer service being lacking. I ordered their TKO 600 conversion kit and it was a bit of a pain to get everything. It took some time but they got me everything.

 

[Don C]

I have used externally mounted clutch slave cylinders, and have always been leery of the internal, hydraulic throw out bearings, too much work involved if they go bad. I've had good luck with the external slaves, easy to adjust, easy to operate without the added friction of pivots and cables. However, there seems to be some inconsistency of the engage/disengage points with them, not a large amount, but noticeable at times.

 

[73' mach 1]

I have used externally mounted clutch slave cylinders, and have always been leery of the internal, hydraulic throw out bearings, too much work involved if they go bad. I've had good luck with the external slaves, easy to adjust, easy to operate without the added friction of pivots and cables. However, there seems to be some inconsistency of the engage/disengage points with them, not a large amount, but noticeable at times.

I'm sure it's all about how creative you can get but you've found an external to work with our cars?

 

[Don C]

No, I haven't looked, as mine has an automatic. Most aftermarket ones are fairly universal. It's just a matter of looking at the clutch fork and what it's motion is and where a bracket can be attached. If you have a top loader you may have to use a push style slave, I don't know if a barcket could be fitted to the side of the transmission. Where the z-bar bracket is attached to the engine may be a good place to attach a bracket. If you have a 5 or 6 speed some of them have threaded attachment points for pull type slaves.

In either case you'll likely have to design and make your own bracket to attach the slave to. It's not that difficult or expensive to make a bracket, easy to make changes to it as needed.

 

[TheDude]

I definitely would have preferred an external or maybe even manual clutch. This unit was in a box with the car and trans when I got it so had to give it a shot as it's all quality stuff and already paid for. But the flip side is hardly anyone around here has worked with this kind of thing and there is a bit of fiddling to get things right. Apparently more than a bit actually as that trans has been in and out a bunch of times already and it still isn't drivable. Guessing someone who actually knew what they were doing could get this right quickly, but I'm not that guy unfortunately.

 

[Don C]

From what I've heard, getting the gap set right can be a challenge, requiring spacers and in and out to get them right, sounds like they never did.

 

[TheDude]

Yes that is correct. There is setting the gap and also there is setting a hard limit on the pedal. If the pedal doesn't have a hard stop, it can make the bearing over extend even if the spacing is set correctly at the bearing. I went over that again and again with the guys I had doing the work, but it never really felt like they were 100% comfortable with what they were doing. I think in the end they just got it working and gave it back to me. So trying now to find someone else who can help but won't break the already broken bank.

 

[Tnfastbk]

Yes that is correct. There is setting the gap and also there is setting a hard limit on the pedal. If the pedal doesn't have a hard stop, it can make the bearing over extend even if the spacing is set correctly at the bearing. I went over that again and again with the guys I had doing the work, but it never really felt like they were 100% comfortable with what they were doing. I think in the end they just got it working and gave it back to me. So trying now to find someone else who can help but won't break the already broken bank.

When all else fails. Call the supplier direct. They have a help line.

https://americanpowertrain.com/

 

[TheDude]

Yup, I reached out and will be talking to them again. They have just been pretty miserable to deal with in the past so I was just hoping to find someone else that had some real world experience with these things.

 

[Tnfastbk]

Yup, I reached out and will be talking to them again. They have just been pretty miserable to deal with in the past so I was just hoping to find someone else that had some real world experience with these things.

That'



That's sad to hear. I have had nothing but good luck from them, as well as their products. But i also dealt directly with Gray, who is no longer with them. I could reach out to him if you would like to pm me number for him to reach you at. He used my car to design the system that they now sell

 

[TheDude]

Thanks. I had heard mostly good things about them as well. I had some small issues I needed help with and just couldn't get a call back. That was on multiple occasions with multiple issues. They were great on the phone, then never call me back or never send the email they said they would. Finally got those little issues resolved, but not crazy about having to deal with them again on this. Of course when I put in a request to get a quote on a full trans kit for a few grand I got near instant response.

Thanks for the offer, let me work more on getting them directly more before doing pulling that pin. And either way I've finally come around to the idea that I will need to pull the trans again and just looking for a plan to move forward. Really am liking the idea of going to an external slave if I can figure out how to get that together.

 

[TheDude]

Hey guys, just wanted to post an update on this for anyone else. So this really boiled down to a botched initial install. The guys I had help with the install just ended up not even looking at the instructions. To be fair, what we had was a box of parts and no directions. The directions we got from American Powertrain after the fact wasn't quite right for this car and the parts I had, so it would have taken a little creativity to make this right. 

Well it turns out they did just about everything wrong and still managed to get technically working. Working meaning it would shift albeit terribly. I finally found a great guy here locally who tore everything apart and put it all back together right. Things were so bad that the master cylinder was actually hosed after less than 20 miles from being installed at the wrong angle and the slave was over extended. I'm pretty convinced that they never even looked at the instructions I gave them as just about everything was wrong. Even if they weren't quite right, the basics were there. Of well, my fault for not doing better homework. 

Now with everything setup correctly a new master and a rebuilt slave, everything is working great and we can finally get on with the rest of this build. 

Thanks for the comments and feedback.