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BJ8 Brake Booster

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BOBBYR

BOBBYR

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Hi Gang,
I hope you are all doing well. I am in the middle of replacing my entire brake system. I wanted to get your opinion on replacing the brake booster. Do you think it would be better to have apple hydraulics rebuild the original booster or would you replace the original unit with an aftermarket type ? I would appreciate your opinion and your experiences on this . As always, I thank you for your help.
Bobby R
 
If its in useable condition then I would rebuild it . The key is you wont know till you pull the servo apart. If the main drum/canister (big black piece) is pitted or corroded inside its junk . The cost of rebuilding it is probably higher than a new replacement servo .
 
I think it would be better to have POWER BRAKE EXCHANGE rebuild the original booster.
Phone #408-292-1305
 
I would get the original professionally rebuilt.

When my servo failed I purchased an aftermarket replacement and had all sorts of problems fitting it on the car. I had to buy a modified bracket as the modern replacements are different to the originals.
In the end I sent the replacement back and had the original re conditioned. They did a great job, looks great and keeps the originality of the car.
 
You could rebuild it yourself. It's not particularly difficult and it's an interesting project. There are rebuild kits available, and you'll want to familiarize yourself with the theory and operation of the servo (they use a 'slave' cylinder to activate a 'master' cylinder; the shop manual has an excellent write-up). You may want/need to have the cylinders re-sleeved, depending on condition. The one issue is the condition of the dry lubricant on the inside of the vacuum (big) canister; if it's gone you'll need to re-coat. Also, there is a leather gasket inside; if it's dry and cracked you probably won't be able to find a replacement (make sure the rebuilder can/will replace it). I did mine about 40-50K miles ago and it's been fine.

I've owned my BJ8 since 64K miles, and the vacuum canister was not painted. I think if the canister is painted black, it has probably been rebuilt before; it seems the rebuilders like to do this. I've seen one instance--not on a Healey--where it appeared the entire 're-build' consisted of painting the canister black.

You didn't say, but why do you want to rebuild yours? If it's functioning properly I'd leave it alone; you can always do it later if need be.
 
BOBBYR said:
Hi Gang,
I hope you are all doing well. I am in the middle of replacing my entire brake system. I wanted to get your opinion on replacing the brake booster. Do you think it would be better to have apple hydraulics rebuild the original booster or would you replace the original unit with an aftermarket type ? I would appreciate your opinion and your experiences on this . As always, I thank you for your help.
Bobby R
Click to expand...
I used Power Brake Exchange in San Jose to rebuild mine and it was about $278.00 plus shipping and their turn-around was quick. They have a certain part that the kits do not come with that is very important(I don't know what the part is) and they do not supply kits. If your's is in working order just paint the cannister.
 
What the rebuild kits don't have: 1) the leather gasket used in the vacuum canister, 2) the seals used on the rocker valve that switches vacuum and ambient air (they should last a long time if not forever, but could be worn or damaged). Also, there should be a check valve on the vacuum line and I've never seen them sold new, but I did get a serviceable used one from BCS years ago (when I bought my car it had a plastic aftermarket check valve).

If you send the body back for re-sleeving be sure to tell the shop DON'T MEDIA BLAST THE BODY; it will damage fine machined surfaces (like the seats for the air/vacuum rocker valve).
 
Hi Bobby,

I believe Bob Spidell hit the points needed to rebuild the Girling booster. Due to a broken air valve, I was unable to rebuild and acquired a Lockheed booster. When finally finding the parts at British Car Specialists, I quickly rebuilt the Girling and have the Lockheed sitting on the shelf ever since.

I found the Lockheed to provide less assist and was ready to eliminate the booster and install a pre-BJ8 MC (as in a BT7). To extend on Bob's Girling-rebuild comments, if the leather seal is destroyed, you can replace the seal, however, it will require some trimming as the supplied unit has, historically, been too large and will drag on the sides of the vacuum chamber if not trimmed. This is a touchy area to address as a fit that is too tight will jam the piston and one that is too loose will diminish or loose the assist from the Vacuum/Atmosphere differential. Last, replacement spray-on lubricant was easily obtained and inexpensive before being designated a Hazardous Material. Today the same dry lubricant purchased in a spray can for $14 can be still obtained a much higher price.

Although I believe the Girling booster can be rebuilt by its owner, any of the conditions mentioned by Bob could make the attempt a waist of time. I also caution that many of the expert services have also made the attempt a waist of time as well so I, personally, would not be that positive on sending my unit before getting some guarantees.

The last alternative is to replace the booster with an aftermarket unit. I understand Tom’s Import Toys carries a PowerTune unit that is a remote booster from Australia (or is it China) that will provide equal or greater assist to the Girling. I was told by a Healey friend in Hawaii, who obtained his unit from a distributor in Australia, that there are multiple modes that will fit nicely with each provides a different level of boost, so choosing the correct unit will require guidance from Toms, or others with experience, to secure the model that will provide the level of brake assist (Girling-equivalent or better) you prefer. I would contact Tom’s to get further information, as I was told the cost of this unit is very reasonable when compared to having the Girling rebuilt and other replacements. I believe these units are sold under different names and some on the list may have some experience and will share.

Good luck,
Ray (64BJ8P1)
 
Hi Guys, Thanks for all your replies. I like the idea of keeping the original booster if possible. Thanks for the advice and the phone number also.
Bobby R
 
Victoria British offers a complete brake servo kit, fittings, lines, hoses, and detailed instructions. These are currently on sale for about $170. I purchased one after I acquired my '60 BN7 about 18 months ago, but have since become accustomed to driving a car without a servo booster. The servo was not available on Series 1 cars, and I am aware there are dimensional differences in the master cylinder bore on servo and non-servo cars. I have fitted the mounting bracket on the sloped front of the passenger side floor. This is where I saw it mounted on cars that had the units. But I am anxious to hear from someone who has installed this kit.
 
rjc157 said:
I agree if its not leaking leave it alone I had Apple do mine and it leaked after a few yrs
Click to expand...

You have to be a bit cautious here.
Geneally a failed booster does not leak initially upon failure.
Because all the fluid is being trapped in the Vac chamber.
This requires that you remove the unit and shake it listening for fluid sloss-ing around inside the chamber.

Additonally, fluid via the vacuum line will enter the intake manilold and a huge white cloud of smoke will follow you every where you go.
 
Keoke said:
You have to be a bit cautious here.
Geneally a failed booster does not leak initially upon failure.
Because all the fluid is being trapped in the Vac chamber.
This requires that you remove the unit and shake it listening for fluid sloss-ing around inside the chamber.

Additonally, fluid via the vacuum line will enter the intake manilold and a huge white cloud of smoke will follow you every where you go.
Click to expand...

Agree - on the newsgroup there have occasionally been postings about mysterious loss of brake fluid unaccompanied by any visible leaks.
 
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