Mico master cylinder

GPster · July 30, 2006, 04:59:53 PM

Years ago Frank Oddo did an article in Street Rodder about Mico master cylinders. The name and the shape stuck in my memory and a few years ago one appeared in a swap meet. I bought it because it was new and it would fit the stock Jeepster mounting. I have 8 pages of notes with what is right or wrong with the Jeepster frame, '78 to '86 GM metric frames, S10 2x4 and 4x4 frames, etc., etc. and so forth. When I put the non-power steering box in the frame I amazed myself with the engineering but when I substituted the 605 power box it got in the way of the master cylinder mount on the stock frame because of the length of the box. Tilting the box up will allow the master cylinder to work and will also allow for a better angle for a column/box "U" joint but it make my engineering go out the window with the Pittman Arm sweeps. Are these master cylinders designed that they will help with a drum/drum brake system to lessen the need for power brakes? I need to know how to add this to my notes which will soon become a (dumb) book. GPster

Fat Cat · July 30, 2006, 05:30:37 PM

You might be able to find a few of your answers here http://www.mico.com

exsedan · July 30, 2006, 07:22:41 PM

I put one of the two stage power boost master cylinders on a '36 Coupe that I built back in the late 70's and early '80's and it is still working today. I did rebuild it one time in that span of time. The coupe has a '73 Pinto front end and a Jaguar rear and it works the four wheel discs just fine. They are a double piston (one within the other) cylinder and give the feeling of power brakes. They do have a strange feel to the actual "push" of the pedal, but once I got used to it, all was well. They were/are actually a fork lift part (probably many other things too). Parts are probably available fron the disrtibutor. The top picture shown in the above link for the dual cylinder, is exactly like the one I installed. Not much has changed in all those years. Last time I bought from them I believe they were in Fontana, California (or somewhere close to there). I just recently sold the car...........jb EXSEDAN

GPster · July 30, 2006, 07:58:31 PM

Quote from: "Fat Cat"You might be able to find a few of your answers here http://www.mico.com

That's a better site than I found on the "Best of the Web". Tomorrow I'll have to print the 31 page catalog so I can read it. Maybe after weeks of bad ideas something will look up. I found a junk yard with all three of my upgrade prospects and maybe tomorrow I'll go with my 8 pages of notes and a tape measure. GPster

GPster · July 31, 2006, 11:28:53 AM

Quote from: "exsedan"The coupe has a '73 Pinto front end and a Jaguar rear and it works the four wheel discs just fine. EXSEDAN

I put in a request for information to Mico this morning. Your explanation brings to mind one more question. To keep things un-complicated I was going to use it on a drum/drum application. If there's no internal check valve that would add something else to consider. That list will be 9 pages before the end of the day. GPster

exsedan · July 31, 2006, 01:57:35 PM

The instructions that came with the unit explained that if you were going to use it with discs and did not need the INTERNAL check valve, "to take an ice pick and punch a hole in the check valve" prior to installation. The instructions actually told in detail how to do that (Remember, this was 25 years ago). When I later rebuilt the unit, I actually removed the "punched" check valve and per the rebuild instructions, left the valve out of the rebuilt unit. I think today, you probably could order it with or without the check valve. The instruction sheet shows a very detailed drawing of all parts and how they go together and operate. It's a real unique master cylinder. My only thoughts on it's installation in the "todays world" of "high tech and law suits" is SAFETY, in that it is not a dual SYSTEM cylinder. Therefore, you are feeding all wheel cylinders from ONE source..............jb EXSEDAN

GPster · July 31, 2006, 02:35:28 PM

The one I have is still factory sealed ( but of course without instructions) That sounds good though, maybe enough of this stuff will get me back on my original track. Remounting my steering box doesn't look so bad if this master cylinder will do the job. Every once in a while a little light seems to cure a hopeless case. GPster

GPster · August 01, 2006, 04:05:46 PM

Now I know a little more about what I've got but I'm still up in the air over if it will help. My cylinder has a primary bore of 7/8" and a secondary bore of 1 3/8" and the steering box can be moved enough to use it. That's 2 pieces that I have that might work. I went to the junkyard yesterday and did some measuring. The GM metric frames or the S10s with the steering box in front of the axel put the steering box 3" in front of the grill on the Jeepster. The S10s are narrow enough in the frame at the radiator to use but the Metric frame is too wide. The motor would have to be slid back in the frame in all instances so there would not be much gained in getting a firewall for pedal mounting and a floor. If someone appeared with a GM metric package with a 60 degree V6 and I had that much running I would try it but maybe there's as much hope in accomplishing my original plan as throwing it all out the window for some that I might be able to drive. I need to clean off the bottom of the "Top Hat" frame and see if there is enough off what's left to have a new bottom put on it. Because of my modifications and the fact that this thing was hot rodded in the '60s it's hard to know if I should hope or not. But my therapist said I have to understand when I'm depressed. I understand. GPster

sirstude · August 01, 2006, 08:59:37 PM

GPster, Can you post a picture of your existing frame? The one my friend had that I could look at to get ideas went to Canada a year ago. He had planned to put a MII in it. A couple of us were going to build our own crossmember, (Not really that hard). and we have another friend that can build the A arms. Just wondering if you could just cut the bad section off and build a new piece out of square tubing. That is what I had to do on the Studebaker when I did it. Too many ex-drag racers had played with it in the past.

Doug

GPster · August 01, 2006, 10:06:23 PM

Quote from: "sirstude"GPster, Can you post a picture of your existing frame? Doug

Not all that easy and the body is still on it and it's behind the garage. If you're not familiar with the "top hat" type of frame construction put in your mind the siloette of a top hat where the sides flare out to become the brim. The bottom of the frame is a piece of metal that goes accross from the edge of one brim to the edge of the opposite brim. Or think of it as an inverted channel with an outward flange welded on each edge and the boxing it not over the channel but from flange edge to flange edge. For the profile of this frame imagine a deuce frame with a higher kick-up over the rear axel and "Z"d up at the firewall. The frames width is 30" from the front to the firewall where it starts flaring out at the "Z" to 40" wide. Yes if you had 2" x 4" rectangular tube and 2" x 6" rectangular tube you might duplicate the form of the frame with sharp angles instead of sweeping bends but nothing fastens to the rectangle, everything fastens to the flanges that the "Top Hat" brim provides so the 2" dimension provides a 4" area with the 1" flange on either side. The bottom of this frame is shot or at least questionable from one end to another and there is a massive "I" beam "X" member that fasten to the top and bottom of the side rails in 4 places. Plus the hangers for the leaf springs hang on those brims in the rear and now with the tube axel in front those (2) springs hang on it too. I truly feel that I might have a greater chance of succeeding if I modify something that rolls rather than designing from scratch. GPster