ukjohn

I've just received a new brake booster, but these parts were rattling around loose inside it. Does anybody know how they are supposed to be fitted? My guess is that the metal bar goes the hole in the center (but which way round?) and the rubber washer goes on top of that, but then I could be wrong!

MelWff

Any reason you are not returning it?
If you open it up and there are other issues the vendor will see it has been opened.

ukjohn

If it's an easy fix and just needs these bits put back in the right place, then I'd rather save the time of returning it. I'm not planning to open the can, I'm hoping I can just put them back in place through the hole in the front of the booster. I should have said they were rattling around in the front section.

MelWff

Isnt the push rod sticking out through the hole?
I see you are in the UK so returning it to the USA is a problem.

ukjohn

My booster isn't quite the same as this drawing, but I think that the rubber "washer" that I have is the "Reaction Disc" in the drawing. I suspect that the metal bar goes behind this. On my booster (it's a 78 by the way) the push rod fits into another cylinder. This other cylinder is what carries the front vacuum seal and would I believe press against the Reaction Disc. Unfortunately I haven't yet managed to find a drawing of this design on Google.

Easy Mike

Contact the manufacturer of your booster. They should be able to explained the uninstalled parts.

71chimera

If you're a home DIYer, suggest do Not attempt opening a booster housing for inspection/repairs; you probably don't have the proper equipment or expertise to correctly crimp & seal it closed. Its diaphragm(s) is easily over-stressed if not cut/holed. Order another booster or locate a professional booster remanufacturing company in your area.

ukjohn

I'm definitely not thinking of opening the booster housing. I'm hoping I can just place the components back in the right order and orientation. I've taken a few more photos which might help explain what I'm looking at.


The booster without it's push rod and front seal, these were just sitting loosely in position when it arrived

The push rod, it's outer sleeve and the 2 bits I found inside the booster housing laid out in the order I think they might go

The booster with the push rod, it's outer sleeve and front seal in place. I haven't fitted the 2 mystery bits as I don't want to lose them inside the housing again, it is a pain to get them out!

MelWff

Have you removed the old booster to compare them?
As already stated contact the vendor or you need the 1978 version of the factory manual.

ukjohn

I haven't taken the old one off yet. The car is due to go for paint soon and I want to make sure I have some brakes (even if not power assisted) for getting it on and off the trailer. I was hoping to do a quick swap over, but could do with a fully assembled booster first. I've tried the vendor, but he wasn't much help, obviously if I can't fix this easily then I'll be back onto him. What manual do you think would have this sort of detail? I can't find anything in my AIM.

7T1vette

CALL the vendor and tell them what you received. We can only 'guess' at what those parts are for. They may be able to resolve your issue over the phone.

resdoggie

Is that a Tuff Stuff booster?

Sayfoo

As hinted above, contact the manufacture, not the vendor.
You may have a universal unit that uses different adapters????
Hopefully you can see what you need when you get your master cylinder off.
And, fyi, you have to make sure you have the correct rod projection for your mc.

ukjohn

I can't find a manufacturer's name on the booster, so no help there. I've got my old booster off now and it looks just the same except that the bit I'm calling the push rod outer sleeve is rigidly fixed in the booster, so I can't pull it out to see what is behind it. Afraid I'm going to have to ask the vendor for a replacement, as I'm not up for guessing how to re-assemble an item as important as brakes. Looks like another delay to getting the car on the road.

resdoggie

Does the rear of the booster look like this?

ukjohn

Obviously it looks very similar, but not exactly the same. The good news is that the vendor has given me a full refund.

Sayfoo

Good on the refund. If you give us the vendor and the part #, maybe we can figure out the manufacturer, and then you might be able to fix it.

ukjohn

I am away from home this week, so can't look for a part number but I don't think there is anything on the booster anyway. My current plan is to assemble it as I think it goes and test it to see if it works properly. If not then I'll buy a new one.

ukjohn

In case anyone else gets a booster that comes in pieces, here's what I've discovered.
First I found this picture, which has the same pieces that my new one does and assembled in the same order that I thought mine should be.

Second I found a warning about a Ford booster that said to be careful not to let the reaction disc fall out, so obviously this problem isn't confined to GM!
Third I took apart my old booster and found it was a very similar design to the picture above and my new booster. As it happens the bit I've been calling the push rod outer sleeve wasn't rigidly fixed in the booster, it was just a tight fit and if I'd pulled hard enough it would have come out.
Finally, I discovered that the small metal bar will only fit in one way round.
Given all this, I've managed to re-assemble my new booster, spent a couple of hours upside down in my footwell fitting it and hey presto I now have power assisted brakes again

resdoggie

Now, see how easy that was?

Glad you got it working.