5 replies to this topic

[aust1n7]

Hello, I need to get this identified as I need to replace. I know its a brake master cylinder, but I can't find any replacement part with the same numbers on. It has AP and then 3211-447C and then Q229.

It has two outlets that are the same size, and a body mounted sensor.

Can anyone shed some light, and let me know the best one to replace this with from the ones available at the usual places.

Many thanks

 

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[Dan]

  Unless the brakes are diagonally split all twin circuit master cylinders should be replaced with the currently available yellow band cylinder, there are various sets of conversion pipes available for the different systems.  Masters with the built-in PDWA like this were superceded in the master parts list many years ago, except for the diagonal split one I believe which you might still find available if you need it.

[Ethel]

GMC167, if you can find one.

 

It's been superceded by GMC227, which is the "yellow band" cylinder with stepped bores and odd sized, metric, outlets. It can't be used on diagonal split systems, just in case yours is.

 

Minispares have conversion pipe kits and more info.

[aust1n7]

GMC167, if you can find one.

 

It's been superceded by GMC227, which is the "yellow band" cylinder with stepped bores and odd sized, metric, outlets. It can't be used on diagonal split systems, just in case yours is.

 

Minispares have conversion pipe kits and more info.

Ethel,

Thanks for your response, do you mean the one I have can't be used on diagonal split systems, or the replacement one you have mentioned?

Kindest

Tim

[Ethel]

The yellow band GMC227 can't do diagonal 'because its stepped bore puts different pressure out of each outlet. The lower outlet, bigger bore, gives lower pressure and should be connected to the rear brakes. It still needs some sort of limiter to stop the rear locking up, but it does give a bit better feel with less pedal travel.

 

If you have a diagonal split, or even if it's front/rear, an alternative is to use the early unservo'd Metro cylinder. It uses the same casting as GMC227, but is the same bore top & bottom, with M10x1 unions.

[ac427]

Thread resurrection.

 

I have the master cylinder on my 1980 Pickup.  I thought it was a GMC167 but the pickup has front to rear split not diagonal split brakes.

 

It could be a GMC 173.  I'll see if mine has metric or imperial threaded unions.