By all means this is not an attackon Mr Lumens, however a caution on purchasing the complete E31 Brake Boosterkit from this source until a change or correction can be made.

I don’t know if this information has been posted or archived, but I wouldlike to caution on this particular product. I apologize for any inconvenience this has caused in the future I will ask for multiple opinions on ANY engineering question.Ī while back I purchased an E31 Brake Booster Rebuild Kitfrom Max LumensĪ Buyer Beware would be in effectIMHO. There are no other substitute seals nor any options besides buying a new cylinder (which, of course, is why I made the kits in the first place). I'm having some NBR seals made up, but it's a slow process because a mold must be made. All the other seals and o-rings are fine and work well just don't go near the rear seal. If your existing rear seal is good and doesn't leak now, don't touch it just leave it alone and use it again. There is a chance that they can leak, even when installed well their engineers made a mistake, and it would seem that poly is not a good choice for this application. They recommended a polyurethane rear seal to replace the original rubber one. When I had the kit made up, I sent an entire booster to the seal manufacturer. It's the one that goes in the rear position and seals against fluid going into the passenger compartment, over the brake pedal. I need to make everyone aware that there is a defect in one of the seals in the booster rebuild kit.

Brake power booster rebuild kit