1987 Def90 Soft Top Rear Drum Brakes...G Valve ??

Guys, looking for clarification here - just refitting new brake lines all round. The old system had no G Valve, just a straight brake line from the twin output MC to the rear flexible. The question is, do I need a G Valve for the 90 Soft Top?

Have searched the internet tonight and cannot find a correct answer. To add to my confusion, the new brake line kit has come with a two piece front to rear brake line :. supplied to fit with a G Valve.

What's the real answer - anyone confirm this?

Thank you

some may say no, but IMO yes you should as it prevents the rears locking up under hard breaking when unloaded, and LR wouldnt have fitted it if it was a waste of time..
You can probably get one from a breakers, there isnt anything to go wrong with them its just a large ball bearing that goes up a slope when you break hard.
I can send you photos of mine if you want.
For a breaker i would recommend 'cornish wreckers' on ebay/facebook etc - there isnt a single part i have wanted that he hasnt been able to supply me

Thanks @flat, a perfect answer. I was in two minds with this. The engineer in me says, yes, it needs to be fitted - the other half of me saying 1. it wasn't previously fitted, and 2, there are a good few LR diagrams for Def90's showing no G Valve fitted and readily available single piece brake lines for sale.

Ans yes, a photo of yours would be very welcome; thank you

Do you need a different master cylinder?
Just checking.....

Thanks @Hicap phill , no need for different MC - I've bought a new Delphi twin MC some while ago that's correct for both with and without the G Valve, though didn't realise at time of purchase - I've checked this this evening.

Do your rears lock up under heavy breaking? Rag tops are a touch lighter at the back so if it were going to lock up now is the time to find out. Do you think you might ever convert to discs at the back?

Another thing to consider is braking in different conditions, snow, ice , rain etc.

v8250 said:

Thanks @flat, a perfect answer. I was in two minds with this. The engineer in me says, yes, it needs to be fitted - the other half of me saying 1. it wasn't previously fitted, and 2, there are a good few LR diagrams for Def90's showing no G Valve fitted and readily available single piece brake lines for sale.

Ans yes, a photo of yours would be very welcome; thank you

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It’s ultimately up to you. I had this dilemma when I overhauled my brakes totally. Leave it or remove it, after much ummimg and aahing I left it.

Will take a photo this weekend of how it’s piped up, not going to dismantle it again if that’s okay

nobber said:

Do your rears lock up under heavy breaking? Rag tops are a touch lighter at the back so if it were going to lock up now is the time to find out. Do you think you might ever convert to discs at the back? Another thing to consider is braking in different conditions, snow, ice , rain etc.

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The rears do not lock up under heavy braking/testing, but...there's always a but...I've yet to try in an emergency situation where/when we need our brakes the most.

Plus, have yet to test with the roof tent on top and the back full of gear. I'm near certain I could force the rears to lock up, with or without the loads. So, I'm going to fit a the valve to be on the safe side.

v8250 said:

The rears do not lock up under heavy braking/testing, but...there's always a but...I've yet to try in an emergency situation where/when we need our brakes the most.

Plus, have yet to test with the roof tent on top and the back full of gear. I'm near certain I could force the rears to lock up, with or without the loads. So, I'm going to fit a the valve to be on the safe side.

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Make sure you get the correct bracket and mount it properly, they have to sit at an angle.

G valve

flat said:

G valve

View attachment 210775

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Have you been leaking claret all over your engine bay?

nobber said:

Have you been leaking claret all over your engine bay?

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red oxide paint. necessity in land rover ownership.
The LR has of course drawn blood from me on numerous occasions.

flat said:

red oxide paint. necessity in land rover ownership.
The LR has of course drawn blood from me on numerous occasions.

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You bleed Red Oxide paint? Thats hard core right there!
Hey, fancy coming round mine and bleeding over my rear cross member?

nobber said:

You bleed Red Oxide paint? Thats hard core right there!
Hey, fancy coming round mine and bleeding over my rear cross member?

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you dont?? i thought land rover owners bleed red oxide or ep90

flat said:

you dont?? i thought land rover owners bleed red oxide or ep90

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I just bleed from the wallet nowadays. Hands like shovels and skin like steel!

All, I have a confession to make. In the back of my mind I thought I had seen a G Valve when dismantling the engine bay last year...so into the conservatory, which is my international Defender parts storage centre...and there, hidden in a box is the G Valve I refurbished November last year! I feel a dork and am humbly embarrassed But thank you for all the help...

At least you found it before buying another