• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

1275 Ribcase transmission in Bugeye - Which slave and pipe?

Share this page

TulsaFred

TulsaFred

Jedi Warrior
Country flag
Offline
I took out the 948 and smooth case, and am about to install my 1275 and ribcase.

My original set up is a 7/8 dual bore master, a 3/16" od pipe with male fittings one each end, which attaches directly to the BE slave. The pipe is 93" long.

The 1275 ribcase set up is a 1/4" od pipe and correspondingly larger thread, with a rubber hose between the pipe and slave. The pipe was apparently only 40" long, so must have been routed differently.

So what is the best set up to use?

I'm thinking I'll just use the BE slave on the ribcase and keep everything stock from the original. Any problems or deficiencies with this simple solution?

Other options?

(BTW I put in the copper nickel brake pipe set from Moss, and now I'm contacting their supplier, Automec, about a matching copper nickel clutch pipe. They can customize that pipe in any way I want)

Fred
 
Fred, I took the end from an old 1275 clutch hose and welded in the correct fitting for my bug eye coiled pipe set up. Another option!

Kurt.
 
TulsaFred said:
I took out the 948 and smooth case, and am about to install my 1275 and ribcase.

My original set up is a 7/8 dual bore master, a 3/16" od pipe with male fittings one each end, which attaches directly to the BE slave. The pipe is 93" long.

The 1275 ribcase set up is a 1/4" od pipe and correspondingly larger thread, with a rubber hose between the pipe and slave. The pipe was apparently only 40" long, so must have been routed differently.

So what is the best set up to use?

I'm thinking I'll just use the BE slave on the ribcase and keep everything stock from the original. Any problems or deficiencies with this simple solution?

Other options?

(BTW I put in the copper nickel brake pipe set from Moss, and now I'm contacting their supplier, Automec, about a matching copper nickel clutch pipe. They can customize that pipe in any way I want)

Fred
Click to expand...

Fred,

It's fine to use the 7/8" salve cylinder used with everything prior to the 1275, but you would do well to upgrade to the 3/4" conversion I provide for the master cylinder. I don't recall if you're upgrading to disc, but I definitely recommend that upgrade for both bores if you are. I can also do just the clutch side. With the 1275 diaphragm clutch, you'll find a significant improvement in the feel of the clutch. The same is true of the brake with discs.
 
The upgraded master cylinder will be on my list when I upgrade to discs later.
For now I guess I'll just buy a new 7/8 slave and keep everything else stock from the BE as well.

Seems like there were issues concerning pushrod lengths with the various set ups ?
 
TulsaFred said:
The upgraded master cylinder will be on my list when I upgrade to discs later.
For now I guess I'll just buy a new 7/8 slave and keep everything else stock from the BE as well.

Seems like there were issues concerning pushrod lengths with the various set ups ?
Click to expand...

Fred, see my web page for data on pushrods and much more.

https://gerardsgarage.com/Garage/Tech/TO_Bearings/tobearings.htm

For the 948/1098, the push rod should be 2-3/8" from hole center to end. For the 1275, the push rod should be 2-11/16" from hole center to end.
 
I keep forgetting that Gerard's website should be my first place to check on such things...
 
If I have a 1275 and ribcase with the 948/Bugeye's 7/8 slave cylinder and master cylinder, do I:

1. Use the throwout bearing and pushrod from the 1275 (more offset bearing, 2 11/16 rod), or
2. Use the throwout bearing and pushrod from the 948 (less offset bearing, 2 3/8 rod)

?
 
TulsaFred said:
If I have a 1275 and ribcase with the 948/Bugeye's 7/8 slave cylinder and master cylinder, do I:

1. Use the throwout bearing and pushrod from the 1275 (more offset bearing, 2 11/16 rod), or
2. Use the throwout bearing and pushrod from the 948 (less offset bearing, 2 3/8 rod)

?
Click to expand...

Fred, check my site again, as all the info is there.

Short version = the release bearing must match the clutch. If you are using 7/8" slave, match the pushrod to the slave.
 
got it , thanks
 
Everything installed and bled (although the brakes don't seem to want to bleed completely...).
Now I can't get the clutch to release. I adjusted the master cylinder pushrods all the way out (maximum length so that the piston begins to move with minimal pedal movement), still won't release the clutch.
I removed and measured my slave pushrod on calipers. It is 2.45-2.5 " from center of hole to end of rod. I think this is the 948 pushrod.

Gerard said to match the pushrod to the slave, which is the 7/8"/948 slave. However, it seems like I'll need to use the longer pushrod for the 1275 (2 11/16" or 2.6875").

Thoughts?

(BTW the measurement of the pushrod I have was made from the very end of the rounded rod to the center of the hole - 2/5". If I measure from the hole center to the point at which the taper begins for the rounded tip it is approximately 2 3/8")
 
Fred,

A piece of Threaded Rod with a Union in the middle will do to get things going until you get the correct rod. Just don't overextend it and bend the folk. That could get things going today.
 
Thanks Jim.
I found an old rusty long pushrod- was actually over 3" long. I think a previous owner of on of my spare trannys must have fabbed it. Anyway, I cut it down to 2 11/16 long and put it in the car.
Still won't release the clutch!
Looking it over, I am thinking the master cylinder may not be giving a full stroke. It may be that the pistons are not fully returning , perhaps bad seals. Barring any better ideas I'll order some new master cylinder seals and see if that fixes it.

Any easy way to tell if the MC piston is not fully returning while it is still in the car?
 
Should be able to feel it by the pedal. You can definitely tell by grabbing hold of the rod that goes into the MC and moving it around.

So, if its not returning then you still haven't gotten the air out of the system?? That was going to be my diagnosis.

Kurt.
 
I think I got all the air out of the clutch system. I didn't think air was a cause for incomplete piston return in the MC. I could be wrong. I think more of deteriorated seals jamming the bores and not allowing piston return.
 
TulsaFred said:
I think I got all the air out of the clutch system. I didn't think air was a cause for incomplete piston return in the MC. I could be wrong. I think more of deteriorated seals jamming the bores and not allowing piston return.
Click to expand...

No, what i meant is that if the MC is giving trouble you might not have gotten all the air out and that could have something to do with the clutch not wanting to release. I've had those MC's apart several times and they do have to make a full stroke to allow fluid and air to move freely in and out.

Kurt.
 
I had the car on the lift and my daughter operating the clutch pedal. I took the rubber dust boot off the slave and watched as she depressed the clutch. Full travel confirmed. I took of the rubber inspection cover on the side of the bell housing and watched. The pressure plate seemed to fully depress with the actuation of the pedal/slave.
Still no clutch release.

Oddly, yesterday it randomly worked for a short period and I took the car for it's first drive in about 3 years. It was great, the 1275 and ribcase is a big upgrade from the 948 and smooth case I had in it before. Glorious. Motor ran smoothly and strongly and went through the gears on the trans w no problems. Perfect.
Then as I pulled it back into the garage the clutch wouldn't release again. Strange.

So at this point, I am suspicious of a jammed pilot bushing or a defective clutch pressure plate or disc. Not happy to pull the whole engine trans back out to see.
 
Bummer, Fred.

Can you risk driving it some more to see if it will come out of it?

Kurt.
 
Fred,
Did you soak your pilot bushing in oil fir 24 hrs prior to installation? I know it's a long shot, but...
Rut
 
I hate to admit, but I didn't replace the pilot bushing! I felt it with my finger and it seemed "ok". Maybe it is or maybe it isn't...

One thing I tried was lifting the car, putting it in gear (2nd with the sychro and the wheels able to spin got in in gear without grinding).

I revved it slightly, pushed in the clutch and then hit the brake to try to jar it loose. 3 or 4 attempts were a no go, the engine just stalled.

Any other ideas?

I keep telling myself that the fun is in the process not the end result!
 
Difficulty adjusting clutch pedal freeplay?

Possible Causes:
Clutch disc installed backwards
Flywheel bolts improper-head of bolt too large
Flywheel worn-improper resurfacing or too thin
 
Back
Top