17 replies to this topic

[tuxedoss]

Seems nearly all Holdens in the 70s used the master cylinder with the big nut at the end. I've done some searching and seems sometimes they also used one very similar without a nut, had more of a long snout as its been described. Searching tells me they may be made by Delco-Moraine , it was also mentioned maybe  fitted to big Holdens that had aircon, I have no idea on what the relevance of the aircon is with the master cylinder. Now the reason I'm asking is my 76 5L SS has one of these cast iron no nut master cylinders and as far as I know is factory original, the lid says use Delco brake fluid, I can't see any markings on it to indicate date it was made or brand but it was pretty rusty. I've sent it off to be rebuilt as i assume its the original. Now I'm wondering does anyone else have one of these so called long snout master cylinders? Also of interest is my SS has factory air

Edited by tuxedoss, 21 August 2019 - 10:00 PM.

[Indy Orange]

I seem to recall a company in Victoria back in the 70s called Eunuch Master Cylinders ,made and distributed master cylinders with no nuts.

[V-SLR5000-P]

I seem to recall a company in Victoria back in the 70s called Eunuch Master Cylinders ,made and distributed master cylinders with no nuts.

Easy to pick. Brake squeal was always much higher with the Eunuch cylinder.

[Dr Terry]

Yes, there were a few small Australian companies which manufactured cast-iron m/cyls with no nut. Also a few importers brought some GM US stuff. None of these were factory fitted.

 

GMH did fit the US Delco Moraine units (with no nut) in very early HK Holden until the GMH (Aust) made ones (with nut) came on stream.

 

The story about the air con application was again early HK only.

 

Can you believe in early HK if you optioned a 5-litre (307) V8 with factory air con, you couldn't then option power disc brakes. The reason was that the rear of the rather large GM A6 air con compressor fouled the m/cyl because the booster protruded so far into the engine bay.

 

This was fixed around the release of the Monaro & Brougham by changing the booster to a straight thru push rod which moved it closer to the RH inner guard (away from  the engine & compressor). It was obvious from day 1 with the Brougham, because it had the 307 & disc brakes as standard, so you couldn't option air cond !!

 

All LC6, LJ6, LH, LX & early UC Toranas came from the factory with a big nut style master cylinder. There were NO exceptions other than the A9X which ran the late UC style.

 

Dr Terry

[dattoman]

My 4/74 SL had the non nut master cylinder

 

 enginebay.jpg   100.24K   14 downloads

 

[Dr Terry]

I believe that m/cyl not to be an original factory unit.

 

Dr Terry

[tuxedoss]

Interesting info Terry , So from what I can see mine looks just like the one in pic above, I couldn't find any markings on mine but it was pretty rusty, will see if anything shows up after its been cleaned up . I got the car in the 80s so it is possible it was replaced but the lid looked original due to the use Delco fluid stamped on it, which google led me to the Delco Moraine type. 

 

 

 

 

Attached Files

•  IMG_2306.jpg   143.63K   7 downloads

[Shiney005]

Sorry to go off the reservation, but do you think that 4/74 SL has the original fan motor Neil? I would have thought it should have had a Betts.

[dattoman]

Sorry to go off the reservation, but do you think that 4/74 SL has the original fan motor Neil? I would have thought it should have had a Betts.

 

 

NFI

Lots of orig looking stuff on it

But I'm sure its been played with

[SLR576]

I have been wondering the same discussion as it came up as a debate recently.
So if all we’re big nuts as standard
Why do most that you see now and others that have been off the road for 30 years don’t have the Nut?
Cheers


Sent from my iPhone using Tapatalk

[Ice]

I have been wondering the same discussion as it came up as a debate recently.
So if all we’re big nuts as standard
Why do most that you see now and others that have been off the road for 30 years don’t have the Nut?
Cheers
Sent from my iPhone using Tapatalk

More than likely most were replaced in the 70s like most of the original parts on these old jiggers just throw them away and buy new ones

[Dr Terry]

So if all we’re big nuts as standard
Why do most that you see now and others that have been off the road for 30 years don’t have the Nut?
 

Because in those days, when the m/cyl failed (leaking, by-passing etc.) it was cheaper to fit a new PBR alloy m/cyl than kit the old unit. 

 

In most cases the bore of the old 'big nut' cast-iron m/cyl was so pitted they needed sleeving. So a new m/cyl was a more attractive proposition than reconditioning the old one.

 

I used to purchase PBR alloy m/cyls in cartons of 10. If I had kept every old 'big nut' cyl. that I threw away, I would be a very wealthy man today.

 

Dr Terry

[SLR576]

Because in those days, when the m/cyl failed (leaking, by-passing etc.) it was cheaper to fit a new PBR alloy m/cyl than kit the old unit.

In most cases the bore of the old 'big nut' cast-iron m/cyl was so pitted they needed sleeving. So a new m/cyl was a more attractive proposition than reconditioning the old one.

I used to purchase PBR alloy m/cyls in cartons of 10. If I had kept every old 'big nut' cyl. that I threw away, I would be a very wealthy man today.

Dr Terry

Cheers Doc
I see were your coming from.
The Cheap ass buggers now I am going too have too track down a big nut job
Cheers Steve-O


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[dattoman]

If memory serves...I sold you 6 big nuts many years ago Terry

Maybe should have kept some myself

[Dr Terry]

If memory serves...I sold you 6 big nuts many years ago Terry

Maybe should have kept some myself

You are correct Neil. But all of those cylinders have gone to good homes.

 

Dr Terry

[tuxedoss]

I know it was mentioned before someone was making cast iron ones . What years was this happening as in the 80s from memory they were all alloy. And is it possible they were the exact same shape and lid ? As i doubt the aftermarket ones would have Delco on the lid

Edited by tuxedoss, 23 August 2019 - 10:32 AM.

[dattoman]

I've seen some out of Adelaide in cast

ABS was the marking on them

 

The Holden ones usually have that cast underneath

[tuxedoss]

Got it back all cleaned up, the only casting mark on it is a 1 on the front brake line outlet . I think these are non original but an exact copy as the lid I have is original and is the exact same shape .