Converting Clutch...mechanical to hydraulic

[rcbildr]

Today something went wrong with the clutch in my 85 Burb, and I have to pull it all apart...I think the problem is with the thow out bearing. Anyways, I have a bellhousing for the hydraulic clutch set up and I think I am going to use this as an excuse to convert. I was wondering, what is the difference between the clutch pedal for a mechanical clutch and one for a hydraulic clutch? What needs to be done to a "mechanical" clutch pedal so it can be used on a hydraulic set up? Any help will be greatly appreciated. Thanks!

[edman87]

Wasn't 85 the first year for hydraulic? I am in process of doing the same thing to a 87blazer. I would love some replies to this thread since I have a linkage style pedal set installed in my blazer and have the hydraulic master mounted to the firewall but just need a reliable way to attach the master cyl rod to the pedal. The hydraulic pedal set is rather hard to find. I have been looking for a while and cannot come up with 1. If you figure anything out, let me know.

[rcbildr]

Yes 85 was the 1st year for a hydraulic clutch, but I forgot to mention my Burb was originally equipped with a 700R4. As far as I know, the diesel 'burbs all had automatics. All the parts I used for the clutch linkage came from an 82 Blazer. I was told the clutch pedals are not interchangable, but I think I am going to try and find a way to make it work.

It will be a few days or so before I can start working on my Burb, I need to finish my current project and get it out of my shop. Right now I'm doing an engine swap on a diesel short bed 4x4 chevy for my friend....hope to be ready to put the engine in by the end of the night.

Do you have any pics of where the master cylinder is mounted to the firewall? Thanks!

[edman87]

I will have to get you some pics, may be a couple days. There are indentions on the firewall, just drill out the holes. I have already installed a pedal set from an earlier z bar style in my 87 as it was originally a 700r4 too.
The clutch master sits at a wierd angle on the firewall and the way I was planning to do it puts the push rod at a horrible angle, it will work, but I doubt it will last. I will ahve to get you some pics and we might could figure out a solution. I *think* the pedals are interchangeable into the bracket, but not positive. I did drill a 1/2" hole in the clutch pedal to attach the push rod and added a return spring to keep it off the floor during my buildup. I just have not had time or effort to do anything else to it lately.

[edman87]

Ok, here is some pics.
First 2 are the master cyl mounting on firewall. This is a junk master I am using for mock-up. second 2 are my pedal set and clutch master push rod coming through firewall. Hope this helps. Let me know if you figure out the best way to do this. When I get the time, I am going to do some more figuring on my setup.

[edman87]

BTW, no that bolt was not planned to be my final solution for attaching the push rod to the pedal, just to try and figure some things out. The push rod will definately have to stand out from the pedal 1-1 1/2"

[rcbildr]

Thanks for the pics, it will definitely help. Right now it looks like it will be at least a couple weeks out before I can start work on my Burb. The biggest setback was my paycheck getting messed up, due to a computer glitch I was shorted close to 9 hours of OT on my last paycheck. Then to make things even worse, my Burb broke down and my back up vehicle (84 Ranger) broke down on me too...over the last few days i've had the worse luck keeping my vehicles on the road. Fortunately, my Ranger was a pretty easy, and I've made some more progress on my current project. Contact www.justchevytrucks.com if you want to buy a hydraulic clutch pedal setup. They've really helped me out with my Burb.

[rcbildr]

Originally Posted by edman87

BTW, no that bolt was not planned to be my final solution for attaching the push rod to the pedal, just to try and figure some things out. The push rod will definately have to stand out from the pedal 1-1 1/2"

Sorry it's been a while. I got my Burb fixed by just putting in a new throw out bearing. I am still not happy with the mechanical linkage, but I will have to live with it for a while. I am working on getting a mazda B2000 driveable and once that is done I am going to work on my Burb some more.

I was wondering, What's wrong with the bolt set up you are using? Does the bolt bend?

I've been doing some more reading about the conversion and it looks like I may have a another issue with the conversion. I guess the hydro-boost brakes makes things a little more complicated....not 100% sure on that tho. Thanks!

[edman87]

As for the bolt, I think it needs to be braced also with the push rod attaching at one end and the pedal being at the other end. It is grade 8, but would hate for somthing to go wrong with it, so some kind of bracing will have to happen if I go this route. I also wanted some kind of bushing to keep the squeak and rattle down. I have not even touched it in a couple months, will have to get on it later.
I don't understand how the hydroboost would affect the hydraulics. If anything it should help with it as the hydroboost is way smaller than the vacuum unit.

[rcbildr]

I will have to do some more searching on it i think it had something with how the clutch master cylinder bolted to the firewall...will post if I find anything more.

I have to do something about my Burb, something is wrong with the pressure plate....can't seem to get a break, I fix one thing and then something else comes up Oh well, I'll get it figured out.

I see what you mean about the bracing. I wonder if a large piece of round stock, something about twice the diameter of the nuts there, would work as a spacer.

Did you do anything to reinforce the firewall where the master cylinder bolts up? Will it flex at all as it is now? Thanks!!!

[edman87]

The firewall shouldn't flex as it is. It had no reinforcement from the factory with the hyd clutch.
As for the spacers, I have some brass ones and some nylon, but this was just my mock-up.
I looked at my buddy't factory 86 hydraulics a little yesterday. I need to take my camera and a tape measure over there and get some specs on it. Anyway, it seems that I have more stroke than the original on my master cyl push rod. I will measure his setup for placement and stroke when I get a chance.
Also, I want to check and see if the pedal will interchange into the older style bracket-I think it will, but not sure- as this would make it easy to just swap the pedal into the bracket that I or you already have. If I could find 1 in a wrecking yard, it would be a lot easier to remove the pedal instead of the hanger also, no need to drop steering column and such.
1 day I will get a chance to go and browse the yards around here and see if I can come up with somthing.

[rcbildr]

I've been going to the local pull a part here and all they had for full size chevies was two 2wd trucks and a 4x4 suburban....I'm thinking about making some calls to other yards and see what they have. The trip wasn't a total loss, the burb had a good windsheild so I grabbed that. There is a pedal and bracket for a hydraulic clutch on ebay right now. If I wasn't working on my b2000 I would bid on it. My neighbor was telling me he would use Toyota parts, but that was on a Jeep with a chevy bellhousing. He used to make adapters for a local 4x4 shop. I may talk with him some more when I get to working on my Burb again. I already have the hydraulic bellhousing at my place and I pulled the clutch too. That was on a chevy diesel and the really cool thing is it looks like the clutch has not seen much use.

I just wish the parts I ordered for my B2000 would arrive. Then I can get that done and start working on my Burb. I think this time I am going to fix the clutch and the tranny noise, try to put a lift on it (if I have the $$) and hook up my winch, just got a nice winch bumper the other day too. I am also thinking about just fixing/replacing the clutch on the Burb because it is the cheapest way to go and wait on doing the hydraulic conversion....just have to see how things go. Thanks!

[edman87]

I saw the 1 on ebay, might get pricey. I did do some playing with mine today and think I have it figured out. Before, the pedal was too close and bottomed out the master cyl about half way to the floor. That was with enlarging a factory hole to 1/2" and doing mock up with a bolt with 2" space between pedal and push rod.
I re-thought it and tried moving the pushrod up to another factory hold and it was too far to the other extreme. So, I un-bolted the pedal and drilled a 3/8 hole in between the 2 and checked the fit again, seems to be perfect!
I only went with a 3/8 hole this time because I want to use a nylon or such bushing in the pushrod eye to keep down wear and squeaks- I think it would wear pretty quick without it.
I plan to do some more work on it fairly soon and make sure it will be fine. I also thing I can space or tweak the master cyl and not have to use a spacer so I can attach the pushrod directly next to the pedal.
It seems I will be able to use this setup.
I will let you know my progress soon and get some pics.

[rcbildr]

I must admit, I found a hydraulic clutch pedal set up and I decided to buy that. Right now my Burb is on the back burner and will be for a while. It is still driveable, but I don't trust the clutch that is in there. I also found a removable center floor pan that's from an 82 4x4 truck ( I think). It is for an automatic, but cutting the hole for the SM-465 shifter shouldn't be difficult. I'm not sure how easily it will adapt to my suburban, I think I can make it work tho. I'm going to acquire all the parts I need to get my Burb the way I want it and then do all the work at once.

I'm still fussing around with the Mazda. One of the parts I ordered will not work so I am waiting for another one to show up. The battery tray is rusted out and so is much of the fender underneath it. I ordered a marine battery box and planned on bolting it to the core support and inner fender. The box I bought is too big so I bought the next size down....waiting for that to arrive.

[edman87]

I know the feeling on projects, my k5 was supposed to be on the road 2 years ago! I am right now lining up a 92 samurai to buy- like I really need it to add to the collection.
I do need to finidh up on the k5, so I can justify another project though. Glad to hear you found a pedal setup, it is slim pickings around here.