41 replies to this topic

[jd lj]

My car currently is running an xu1 brake booster with an aftermarket type master cylinder. The xu1 booster has a short push rod, which only protrudes slightly past the face of the booster.

I'm interested in fitting a "big nut master cylinder ". I have one already reconditioned to suit a long push rod available to me, date coded early July so correct for my late July car.

The original standard gtr brake booster from my car has a long push rod, which protrudes almost level with the studs for bolting on the master cylinder.

Can I simply put the long standard push rod into the xu1 booster and use the big nut master cylinder that's set up for a long push rod.

Otherwise I have another big nut master cylinder date stamped 1974 so presumably from an LH Torana in the shed that needs reconditioning. When I attach this one to the standard booster (with the long push rod) it won't go on all the way. So I don't know if this one is set up for a short push rod or just seized up. If it is to suit a short push rod should I just reco this one instead of buying the other master cylinder mentioned at the start?

I hope that wasn't too confusing.

Thanks James.

[dattoman]

LC ran the short rod

LJ ran the longer rod

 

I believe your car is an LJ so the long rod is what you want with the corresponding master cylinder.

 

The LJ and LH master are the same so should bolt up the same

Change the nut on the end and no-one will be the wiser

[N/A-PWR]

and there is adjustment at the front of the rod, and adjustment at the back of the Booster pivot point James,

Just make sure your brakes work before You go for a Spin. Dave I

[jd lj]

But can I put the long push rod from my standard lj booster into what must be a Lc (as it has a short push rod ) xu1 booster?
Or are the push rods not inter changeable between standard boosters and xu1boosters.

JD

[N/A-PWR]

I can almost say James,

they all fit, it is the length that is different, just muck around with them, till one fits right. Dave I

[dattoman]

A single diaphragm pushrod will be too short for a double diaphragm booster

So no you can't

[N/A-PWR]

Datto is Right,

Double Diaphragm Booster Rod lengths are much longer. 

My one here is 180mm long ( from back to Front, Total Length ). Dave I

[jd lj]

So I'll have to reco the master cylinder in the shed to suit my xu1 short push rod brake booster and not worry about getting the already reconditioned master cylinder which suits the long push rod.

JD

[N/A-PWR]

Gees,

is the XU1 Booster a single Diaphragm one James,

I thought, all XU1 Boosters were Double.

I may have a lesson here. Dave I

[dattoman]

XU1 is double

And the shorter rod one is LC

 

If your car is LJ you want the longer rod version

The master cylinders are different and won't be correct for your car 

They are different shapes to look at and easy to pick

 

Though it is possible (once you check of course to make sure) . to swap the piston from the master from one unit to the other to make the correct depth to suit the booster your using

 

 

[jd lj]

Yeah I'm running a double diaphragm xu1booster as pictured above which has a short push rod. I have no intentions of fitting a Lc type master cylinder as I know it would be incorrect in my car, however I spoke to a guy who reconditions them who said he can set up my existing booster for either a long or short push rod and I just need to specify which I need.

I wanted to know if I should spend the dollars on getting that done or buy this cheaper one and just swap my push rods over, as this would be a cheaper option.

From what you guys have said so far it sounds like the cheaper option won't work as the push rods from the xu1 booster and standard booster aren't inter changeable.

JD

[N/A-PWR]

if you have both Rods,

They would both fit me thinks. James

[jd lj]

Datto is Right,
Double Diaphragm Booster Rod lengths are much longer. 
My one here is 180mm long ( from back to Front, Total Length ). Dave I

Ok I just measured the standard lj push rod and we have then :
Lj xu1 length = 180mm
Std lj length. =107mm

Can anyone add the lengths of the Lc push rods and we'll make this thread actually informative instead of confusing.

[dattoman]

From memory the rods are either 8mm or 25mm protruding from cannister face

 

So LC is 17mm shorter than LJ in both cases

[jd lj]

Today I spoke to a guy who said that the difference between the long and short push rods is only in the threaded rod at the end and that the main body of the push rod is the same for both.

So if you need to convert your push rod you can get the appropriate threaded rod from your local fastener shop and loctite it in at the correct length.

Dave I. is your 180mm push rod from a Lj (long type) or Lc (short type). I had assumed it was a Lj but I would just like to confirm this.

Cheers James

[dattoman]

Thats actually not correct. They are definatly different pushrods

 

But yes you can use a longer bolt in the end to do the job but you need to round the end off to suit the original profile so it doesn't cause issue with the back piston

[N/A-PWR]

Hello James,

it is a LH long type, which is the same housing as an XU1 Booster,

all that is different from the two, is the input connection and length at the back.

The rod is 25mm out from the housing on the M/C side, when the 180mm rod is installed. Dave I

 

Today I spoke to a guy who said that the difference between the long and short push rods is only in the threaded rod at the end and that the main body of the push rod is the same for both.

So if you need to convert your push rod you can get the appropriate threaded rod from your local fastener shop and loctite it in at the correct length.

Dave I. is your 180mm push rod from a Lj (long type) or Lc (short type). I had assumed it was a Lj but I would just like to confirm this.

Cheers James

[jd lj]

Thanks for the info Dave. Just out of curiosity how far does the threaded rod protrude out from the rest of the push rod. I'd just like to confirm what I was told today, I can't see why it wouldn't work.

James

[S pack]

Neil, PBR Pt No. VH2178. What is it?

[dattoman]

Number looks familiar

But I can't place what it is

Might be a very old number

Its obviously a booster part as it starts with VH ... but I don't recall the rest

[S pack]

LC or LJ booster m/cyl pushrod?

[N/A-PWR]

7mm of thread James,

I guess what is said, is that you can do the extension, but Brakes are to work, meaning, you wouldn't like them to Fail Hey. Dave I

 

Thanks for the info Dave. Just out of curiosity how far does the threaded rod protrude out from the rest of the push rod. I'd just like to confirm what I was told today, I can't see why it wouldn't work.

James

 

 

 IMG_4949.JPG   37.83K   11 downloads

 

 IMG_4950.JPG   11.58K   12 downloads

[dattoman]

LC or LJ booster m/cyl pushrod?

 

I have to find my hard parts catalogue in the catalogue room to confirm that one

That could take about 6 mths

Where did you get the number ?

[N/A-PWR]

see the disc,

it is at the front of the booster, so it seals the Vacuum, a threaded extension wouldn't seat there,

but if a shorter rod made it to there, and extension thread will work for the extra 17mm

[S pack]

I have to find my hard parts catalogue in the catalogue room to confirm that one

That could take about 6 mths

Where did you get the number ?

NOS XU1 m/cyl pushrod.