27 replies to this topic

[Indy Orange]

Hi all,I have a LC big nut master cylinder which has been fully reconditioned,however the piston depth is deep (LJ standard type)I have the LC shorter pin in the booster. Can I just find a standard LJ booster piston and use that instead of the LC one?Thanks Paul.

[S pack]

Hi all,I have a LC big nut master cylinder which has been fully reconditioned,however the piston depth is deep (LJ standard type)I have the LC shorter pin in the booster. Can I just find a standard LJ booster piston and use that instead of the LC one?Thanks Paul.

Yes, they are easily swapped if you can get the LJ type pushrod to suit your booster.
 

[Indy Orange]

Thanks Dave.

[Indy Orange]

I’ve just about had enough of this car ( had to walk away) so I managed to obtain a what I believed to be a longer booster pushrod from a generous forum member , I took my booster off and fished around in the booster for the reaction disc which I found , I thought missing this might be one of the reasons I wasn’t getting any brakes . So re assembled everything including the pushrod and reaction disc , and you guessed it ! No bloody brakes .I have a big nut master cylinder with a deep piston in it , it was purchased on eBay for a LCGTR however the primary piston is the deep one . What length rod do I need for this ? I though I had the long version. Or do I need a shorter piston in the master? Not happy now I probably have to take the booster back off to fish out the reaction disc again . Really don’t want to take the master cylinder off again either and back to PBP to get a piston changed over .Any help greatly appreciated Paul.

Edited by Indy Orange, 25 September 2021 - 07:15 PM.

[Indy Orange]

The only thing I can think of it’s that the master cylinder may be set up for XU1 large brake booster? Longer rod again ? I don’t know.

[S pack]

M/cyl is the same for both single and double diaphragm boosters.

Even with the reaction disc missing you should still have brakes (albeit they will be violent in their application) if the pushrod is the correct length for the m/cyl.

You need to undo and ease the master cyl away from the booster and measure the length of pushrod protruding past the face of the booster.

[Indy Orange]

Hi Dave , the rod just protrudes beyond the booster , just the dome nut though.However the piston in the master cylinder is around 40mm deep.

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[S pack]

No, that is about correct for LC (about 8mm if memory serves me correctly) not LJ.

LJ should be around 25mm protruding past the face of the booster.

[Strat]

Hi, 

 

just had my XU1 booster reconditioned and he had to make me a new rod, he also reconditioned my big nut master cylinder and adjusted booster master cylinder clearance.

 

Hope this will help you

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[Indy Orange]

So I must have another short LC pushrod😩

[Indy Orange]

Thanks Nick , so that’s the same master cylinder piston depth as mine , and that push rod looks longer.

[Indy Orange]

Yeah I believe that’s correct push rod for LC and a VH212 booster . It has to be the master cylinder piston depth which is wrong for my LC.

[S pack]

Yeah I believe that’s correct push rod for LC and a VH212 booster . It has to be the master cylinder piston depth which is wrong for my LC.

The pushrod currently in your booster is one you recently bought and was supposed to be from an LJ or LH booster?

 

How does the pushrod you got from the forum member compare to the length of the pushrod you already had?

 

LJ pushrod for single diaphragm booster should be about 100mm long from memory..

Edited by S pack, 25 September 2021 - 09:33 PM.

[Indy Orange]

Yeah Dave , I took it as being the longer LJ one.

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[S pack]

measure the overall length.

[Indy Orange]

80 Dave .

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Edited by Indy Orange, 25 September 2021 - 09:54 PM.

[S pack]

Yeah, LC should be about 17mm shorter than LJ which means LC pushrod is about 83mm overall length.

 

Next need to remove the rod from your booster and compare it side by side with your old one.

 

Looks like the acorn nut shaped tip has been adjusted right in on the one currently in your booster.

Perhaps there may be enough adjustment available to get the extra 17mm you need?

Edited by S pack, 25 September 2021 - 10:16 PM.

[jd lj]

Copied and pasted from my previous thread on the pushrod lengths.
Std
Lj =101mm
Lc =84mm. (101 -17 shorter than Lj's)

Xu1
Lj =173mm. Dave I. Has 180mm from a LH Torana , however S Pack has 156mm Nos item (Lc xu1) so 156 +17 =173 mm
Lc =156mm as per S Pack's nos item.


Here's a link to the thread.
"xu1 booster push rod length - Page 2 - Brakes, Wheels and Tyres - GMH-Torana - Page 2" http://www.gmh-toran...d-length/page-2

[Indy Orange]

Dave the one I have I my booster unfortunately is a shorter type like the one I received ,I thought that would be the LJ long type .
James , thanks for that measurement info mate, I got my measurements wrong,so it seems I now have to find a LJ type pushrod 101mm long , I’d rather do that than take off the master cylinder, travel 4 hours to get the piston changed , then travel 4 hours back .
You definitely live and learn with these cars , just when you think you’ve nearly finished, you haven’t really.
If anyone has a long type LJ pushrod to sell I’d be interested 101mm long , cheers fellas.

Edited by Indy Orange, 26 September 2021 - 11:32 AM.

[S pack]

Try that wrecker in WA with all the brake boosters I posted a link to. I believe Datto said the LJ & LH Torana single diaphragm boosters have the same length pushrod.

[Indy Orange]

Yeah I will , thanks mate.

[S pack]

Yeah I will , thanks mate.

Here is the link. https://www.gumtree....lden/1186579961
 

[Indy Orange]

Thanks for your help.👍

Edited by Indy Orange, 26 September 2021 - 12:41 PM.

[Strat]

Hi the person that I used to reco my booster will extend your shaft to the measurement that you specify for $15 just another option.

[Indy Orange]

Thanks Nick, that’s another option if it proves hard to track down .Thanks mate!