LB0442
Well-Known Member
About 10 years ago I had this booster redone by an individual, I guess I won't name him but he is well known for his lack of customer service. I shipped it to a state just north of Texas. After 3 to 4 months, numerous calls, I finally got it back. Installed and it would not hold vacuum for more than a few seconds after shut off, seemed to work ok otherwise. Zero response to emails or calls. This guy has a you tube video on the exact problem, same booster and basically tells the customer he is full of s##t. He even shows the email with the customer name on it. He says they should only hold vacuum for 10 to 15 seconds, that is absolute garbage, the exact definition of a vacuum leak. If you had a vacuum advance or choke pull off leaked down like that you would replace it. He goes off on how the engine is just a vacuum pump and that's the way it was designed. Yes it is a vacuum pump but it has to pull in the air in a metered way, not through the booster.
I have only driven it about 3000 miles since then, life gets in the way. I finally got tired of that and took it apart.
You have to release the outer band and then the 2 halves come apart. The spring is not as bad as every thinks it only pops up about 2 inches. I did it in the press so it would be a slow release.
The center part in the diaphragm has to be turned to get out, it obvious when you see it. Then I made a stupid mistake and took it out without relieving all of the pressure, the center pieces dropped out.
Soooo, I had one out of a parted out vehicle to try this again. You can see in the picture 3 plates and 2 rubber rollers, with a spring under them. The 3rd rubber roller goes in the center of the plunger.
Side picture.
This is the plunger from the pedal, it is staked together and I made a tool to pull it apart. 2 seals inside it.
Here is 1 of the problems, it is hard to see but there is NO WAY this was removed before because you have to re stake it upon assembly. That had never been apart.
I got this kit from Harmon Brakes. Parts look to be very good quality. Did have a couple of issues, the front seal was really difficult to get the lip seated, was slightly different than the factory. Second was the diaphragm, when I installed the center section it was not quite straight, slightly off of 90 degrees. It is turned in so it was probably the crimps for it were off a little. I took it back out and it still would not turn in perfect. Since it has rubber all around it still moved in and out just fine, so I put it together.
I forgot to mark it when I took it out so I left it loose, set it in the holes and turned it level (garage floor is level). Tightened it up and took it out for testing.
I used my A/C vacuum pump with a tee to a gauge. Ran it up to 18", clamped the line and put a cap on it. It took 3 min 50 sec to get down to 15" and 7 min 5 sec to get down to 10". A whole lot better than it was. So I exercised it about 3 or 4 times, ran vacuum the pushed on rod, worked perfect every time. Then I decided to recheck it for some reason, started out at 18.5", took 8 min 42 sec to get down to 15 and then 11 min 55 sec to get down to 10". Big difference, possibly getting the lube all through the seals and they seated better?
I have only driven it about 3000 miles since then, life gets in the way. I finally got tired of that and took it apart.
You have to release the outer band and then the 2 halves come apart. The spring is not as bad as every thinks it only pops up about 2 inches. I did it in the press so it would be a slow release.
The center part in the diaphragm has to be turned to get out, it obvious when you see it. Then I made a stupid mistake and took it out without relieving all of the pressure, the center pieces dropped out.
Soooo, I had one out of a parted out vehicle to try this again. You can see in the picture 3 plates and 2 rubber rollers, with a spring under them. The 3rd rubber roller goes in the center of the plunger.
Side picture.
This is the plunger from the pedal, it is staked together and I made a tool to pull it apart. 2 seals inside it.
Here is 1 of the problems, it is hard to see but there is NO WAY this was removed before because you have to re stake it upon assembly. That had never been apart.
I got this kit from Harmon Brakes. Parts look to be very good quality. Did have a couple of issues, the front seal was really difficult to get the lip seated, was slightly different than the factory. Second was the diaphragm, when I installed the center section it was not quite straight, slightly off of 90 degrees. It is turned in so it was probably the crimps for it were off a little. I took it back out and it still would not turn in perfect. Since it has rubber all around it still moved in and out just fine, so I put it together.
I forgot to mark it when I took it out so I left it loose, set it in the holes and turned it level (garage floor is level). Tightened it up and took it out for testing.
I used my A/C vacuum pump with a tee to a gauge. Ran it up to 18", clamped the line and put a cap on it. It took 3 min 50 sec to get down to 15" and 7 min 5 sec to get down to 10". A whole lot better than it was. So I exercised it about 3 or 4 times, ran vacuum the pushed on rod, worked perfect every time. Then I decided to recheck it for some reason, started out at 18.5", took 8 min 42 sec to get down to 15 and then 11 min 55 sec to get down to 10". Big difference, possibly getting the lube all through the seals and they seated better?
