Just got my '63 Midget back together. Gearbox swap. First time. Went okay. Has all four gears and reverse.
Now, it has what I think is clutch spin. It had it before the swap too. I noticed a drip of fluid on the clutch slave dust boot, wiped it, it came right back so, I'm hoping all I have to do is rebuild the slave.
Symptoms: crunch into 1st (at a dead stop) crunch into reverse from a dead stop, very little pedal travel, take up is almost immediate as you release the pedal.
I've grounded the car as I don't want to hurt this gearbox!!!
Am I on the right track?

PS
What size flare nut wrench is correct for that line?

Yes. 7/16" You should only need a 7/8" cup available at many local parts stores, and you can usually remove the piston, clean, and install cup without removing the slave which is a HUGE time saver.

Peter C.

Air in the line. It is hard to get out. You don't have a full pedal. Its real hard to bleed the air out in the normal fashion.

Air.
I noticed some PO had (I don't think this is OEM) 3 or 4 coils of line on the way to the slave. Too lazy to get the right length? Or are those coils useful somehow?
I asked at NAPA about just getting a 7/8" cup, NO.
Found place in town with the "kit" cup and dust boot, for $10 which is silly but oh well.
Did I mention I got the new gearbox in and engine reinstalled and I DROVE IT! Pretty happy with myself......so far.

Concur. Slave seal is FUBAR. You can get that cup from a local NAPA if you get a counter person with a clue. Bleeding the system is a pain but BE PERSISTENT! If you can get a second body to sit in and operate the pedal, have them push the pedal to the floor ONE time and hold. Measure that travel, cylinder bore end to fork extension... then have the "pumper" stroke the pedal thru full travel at least three and better four strokes and hold it to the board again. Measure that distance from slave to fork again and if it exceeds the first measurement you have air in the line. More bleeding. It can be a process, but patience is the answer. Capture the fluid with a small hose and bottle from the slave so you can "recycle" the fluid and keep the M/C level up. If the M/C sucks air, you gotta start all over again.

My kids know the bleeding routine! Napa guy was not interested in the 7/8"s cup. Too bad I didn't add that to the two orders from VB I got last week. I have a set of hard lines in the pile o' parts from the PO, maybe one is the right length for the slave. Don't see them in the VB or Moss catelog. Usually I won't disturb a line if I don't have too, the one going into the slave looks like it was done without a flare wrench and I'm loath to touch it because that means I'll replace it so, a rebuild "in situ" sounds good to me. Hopefully you can bleed through the passenger footwell inspection hole?

Ummm... yeah, but "kids' hands" are more suited to the space allowed... unless you've owned/maintained a Lotus in the past.

i lean over the front of the car
and stuff my hand in there......z

Those coils are actually supposed to be there. It is a hard line right? Those coils are supposed allow for movement of the drivetrain vs the body.
So, be happy, if not original, then the PO knew what they were doing when they replaced it! (good sign!)
Good job on the tranny..that is one thing I have not dared to venture into yet..

Cylinder rebuilt and bleed. I got a rebuild kit (cup and dust boot) from a local shop off the shelf (they specialize in old stuff) for $10 which is no bargain, but not paying shipping and not having to wait is worth it.
Rebuild went fine. I measure about 1/4" of travel before I started. Once done and bleed I hoped to see improvement but it seems pretty much the same amount of travel to me. Maybe the master is begging for a rebuild too.
No road test yet as it's too late now. At least it wasn't leaking anymore.
BTW bleeding through the inspection plug was easy, probably why it's there. I took an old 7/16" wrench and bent the box end a bit more so it angled right through the inspection hole, clear tube to old 20oz. pop bottle. Stopped bleeding when fluid was clean again and no bubbles, refilled master (with fresh fluid) twice during the process, hopefully it never got low enough to suck air!

Bummer, no better. How much movement of the slave push rod is expected? Hopefully it's just a bleeding issue and I have air yet. Or read somewhere (here?) yesterday that the linkage can wear at the master.

Not so much wear at the master as maybe an adjustment of the rod length!! But check (and double-check) bleeding first...never fully done on the first try!!!!

By rod length do you mean push rod from the master, up against the stop screw on the pedal box? Isn't that just pedal free play? Maybe the main cup in the master is letting fluid leak past, not external, just not creating sufficient pressure? I had this on my Opel's brakes. I guess I'd better rebuild the master too. I just rebleed with the extremely competent help of my 8 year old son. I've pushed a lot of fluid through it and see no bubbles, not that there can't be air trapped somewhere and the fluid just goes right past it but I did try the 40 rapid pushes method, which I read can dissipate the air bubbles and hopefully help them past the high spots. No luck though, clutch simply isn't engaging enough to keep the gearbox from spinning. I can sit at idle (in gear) with the clutch in fine but going into gear from neutral brings grinding, at low idle I can slam it home and go but that isn't cool. Going into other gears doesn't seem as smooth as it should be either. Master rebuild I guess, then bleed like a mutha again and see where I'm at. Shoot, was really hoping to drive it again.

If there is too much free play you will not get the right stroke. It should be fairly tight with just a smidge of free play! I would wager that there is still a bit of air in the system yet though (It IS a bear to bleed thoroughly!!)

Free play is okay then. With the pedal up, I set the stop screw with just a bit of clearance so pedal free play is minimal. Which didn't help at all of course. Either the master needs help, there is air (and I don't know how else to bleed it more thoroughly, I know there's devices to help but I'm not convinced they're any better than the two person method.

What's expected range of motion of the slave pushrod? I'm only getting 1/4" inch worth. No idea what to expect there.

i know exactly how u feel...same problem here.
i think 1/4" is expected, but it has to STAY there..

i took my master cylinder loose from the
mounts and hand bled it while holding
it above the car somewhat.. cap off.
lotsa bubbles came out.....squeeze slow,
as itll shoot everywhere if u arent careful...

mine still doesnt work , but im gonna
rebuild the master next......z

I kinda think it should be more. Have you looked at the rod and pedal linkage at the master to be certain the holes of the pushrod and pedal aren't "ovaled" or the pin worn? Excess wear there translates to a LOT of motion *lost* at the slave. And I've seen pins worn to a point they look like mini crankshafts. They will feel reasonable when in the "freeplay" position and spin 90* with pedal pressure which shortens the distance the master cylinder is depressed.

Just one more thought.

my master is/was new...
no pin problem here, nice and tight.....

im thinkin bout adding some length
at the slave rod and checking the results.....
ill still rebuild the master though....z

Umm, changing the length of the slave rod wouldn't do anything for distance the slave traveled. It's the swept area/stroke of the master wot determines the stroke length at the slave, it'll still move the same distance with either length rod. Only thing more length would be needed for would be if the rod & arm were loose (too much freeplay from slave "zero" position to where the T/O bearing begins to engage the clutch). If the freeplay down there is excessive, then I could see the need.

good point Doc.
my whole system is new or rebuit
except for the master....
kinda points fingers, dont it? ....z

ah. Indeed. Got a nice fine brake cylinder hone?

Guy on another forum says you should depress and hold in the slave pushrod/piston during bleeding. Think that matters? I'll certainly try it while I wait on more parts. And I'll double check the wear at the master pushrod/pedal linkage. Can't help but wonder if this clutch spin situation (which was probably there for a long long time) didn't contribute to the demise of the old gearbox. That old gearbox behaved just like this one (grind to 1st/reverse, bit hard to hit other gears) only it would not go into 4th 95% of the time, had metal bits in the case and on the bench 4th would only grab and hold the output shaft sometimes.....consoling myself that swapping gearbox was still the right thing to do and it's issues weren't the result of this whole hydraulic thing......which I highly doubt.

i ordered a master cylinder rebuild kit
from oreillys.....dont know if its
the correct one though....
itll be in tomorrow...........zimmmy

I ordered mine from VB, probably should have just ordered one of everything in the catelog at the rate I have to order lately, would have saved on shipping!
It'll be a race then; who gets rid of their clutch spin first.
As you're a guitar guy, I'll bet my '89 Ibanez S540 that you win......
Hopefully these MCs aren't too hard to rebuild, I've only done two so far, one on a 1500 Midget, one on my Opel, neither with dual.

ive taken mine apart twice already
pointy needle nose pliers....

strange....i happen to have a pre Satriani
Ibanez 540R .....z

Wow, freaky, good taste in cars and axes. I sold off my Ibanez Destroyer DT400, which may have been a mortal sin but I had to have a floating tremelo. Love the 540S. Not that I can play worth a darn but with the whole Guitar Hero thing being so big among my kids and their friends, I'm a hero that I can actually play most of those riffs! Kills me how all these 12-15 year olds are so into 80's Metal, love it!

Oh, yeah, M.G.s......
master cylinders.....

You think you have a bad seal in there yet? I sure hope that's my problem and not something more sinister.

PS does your guitar case fit alright in the Midget?

Weird, this MC looks great to me (NOT!!)
Dirty MC

You got to break the glaze in there Zimmy, No shineyness in the bore. Those seals need that fine microscratches from a hone to grab the fluid and seal properly.

ill check it out kim.....
mine is new from last summer
but i worked it alot learning
how to bleed it and also rode
the clutch alot while my tranny
was sticking in neutral....

hopefully the latter is fixed.....

the clutch works, it just doesnt hold
the pressure long.....z

Well, I've got the MC rebuilt and reinstalled and I bleed like crazy but the results are the same, grind into first, grind into reverse, grind into 4th a tad too.
Still wondering how much slave push rod travel is expected. Suddenly a cable clutch looks brilliant.

Try, just try a 7/16 nut between the slave piston and the push rod. Might not help but then you will know.

Tried that just now either the nut slipped out (I heard something when I clutched) or it had no effect. I might just have to throw in the towel and pay to have it take care of.

What did the bores look like after honing?

Nut can not slip out that piston is tapered like a cone at the rear.

i rebuilt my master cylinder and i believe my clutch is
working now.....
hopefully testing it this evening .....z

Oh, will check back later for your results.

My honing consisted of running fine sandpaper in there, bores were okay, not perfect but pretty decent I thought. Seems like there should be a way to tell what's at fault here, I'd get my MC replaced or redone if I were sure that was still the problem.

a rebuild kit is only $8..
even if it doesnt fix ur
problem its good to have....

i think it worked for me.....z

I did rebuild the MC and the slave. I'm going to bleed it again, maybe make one of these or buy a eezibleed, or something. Doubt it's still the MC, seems I should have made it better or worse after goign through the whole systems so either it's air the whole time, or I'm barking up the wrong tree and I have mechanical issues somewhere.

I built my own little pressure bleeder, went under the car, unbolted the slave, tipped it back (rearward portion/push rod end pulled down) so bleeder is high, had son push pedal while released and closed the bleeder, pressurizer still hooked up.
Still the same though. Any last ideas before I swallow my pride and take it in? BTW the nut did not stay behind the push rod so that was never in play, could try that again I guess. It is the shorter rod, as is correct for a 1098 I believe.

see my new bleed thread as ur last resort...zimmy

Only other thing I can think of is the throw out bearing has been worn down to th' nub. Or did you change the clutch pieces when the box was out?

I've seen bent fork arms too but only from impact, not from normal use.

Push rod for 948 and1089 is 2 3/8 long,

1275 is 2 11/16 Hole center to end.

Tried nut again, much better, almost cured. What does that tell me? Hydraulics still crappy? or what? Anything crazy stupid about just running that way? with essentially longer pushrod at slave? Still a little "nick" when hitting 4th, no grind into 1st (as long as I'm dead stopped).

No, it tells you that the rod that goes into the master cylinder needs adjusted some. It is adjustable, maybe two turns longer.

Run it with the nut in there, no problem. Sounds like you just have worn parts like the clutch fork bushing and the clevis rod clevis at the clutch cylinder. Hay, the car is getting older every day.

Not to worry, enjoy it, you are not causeing damage with the nut in there.

I tried adjusting the push rod at the MC before, no effect, maybe not enough, maybe still being masked by air bubbles, who knows. Great, I'll fiddle the the push rod at MC and just run the nut then. THANKS!

Now for that fuel issue and oil
leaks issue.........

Fuel issue?

Something that occurs to me that no-one has touched on is the possibility that the throwout bearing fork has been bent. It is a long shot, but I have seen it happen!!!

Well, when I had the engine and gearbox all apart, the throw out and clutch disk/pressure plate all looked very new yet (supposedly only 2,000 miles (and 20 years) on them. I opted to put them back in. The fork was on the donor tranny and I didn't think to examine it for much of anything, looked the same as the one on the box I took out. I did examine the linkage points and all that, nothing was worn hardly at all. Maybe there's a bushing missing off the shifter fork or something and I've got to compensate for that. Don't know.

Yes Fuel issue I won't start another thread because I think I've got it already, seemed like the SU electric pump would cut out, riding down the road, under load or going fast I'd have fuel starvation. When sitting working on stuff the pump would turn off, don't know if this is by design or not.
Had a decent Carter pump sitting on the shelf so I swapped them out.
Same problem, perhaps even worse!
Next changed the see through filter that was right before the Weber and had no more issues, although it sure "looked fine". Don't know for sure it's all cured as it was intermittant but I'm hoping.

Oil leak:
had it bad between spin on adapter and housing, Permatex got that but now it seems its coming out of the block/housing joint. Not too big a deal to pull it off and reseal it.

Oil pressure runs a constant 60 though, never seems to change much either, hot or cold, idle or high revs, doesn't very much that I've noticed.

Pressure should vary. Down to about 20 at idle and 40 or so on the road. 60 at start is good though.