Same here. An -6an fitting on the check valve size is fine, but now connecting it to the 3/8 barb on the vacuum block is the key.
Vacuum brake questions
- Thread starter ttypewhite
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Same here. An -6an fitting on the check valve size is fine, but now connecting it to the 3/8 barb on the vacuum block is the key.
- Joined
- May 26, 2001
- Messages
- 9,208
Just wanted to make a couple comments in general about the vacuum change-over in a turbo car that may be of some help when doing this job as I have been doing many of these since the 90's. 
First, be sure the vacuum supply hose in not vulnerable to gas or oil fumes , and the inside will not come apart or collapse over time? Most parts stores carry a specific type hose for vacuum applications, and the type I use is actually a 11/32" hydraulic hose size.
Also, if the master cylinder is properly bench bled and installed correctly, there is no need to bleed the wheel cylinders if the hydraulic system integrity was good at the start.
After a couple recent jobs, I have found the rear wheel cylinders started leaking after some miles. The master cylinder of a vac booster is different from a PM as it supplies more pressure to the rear shoes. The 25-26 year old wheel cylinders may not be up to the task of handling this increased load for very much longer?
First, be sure the vacuum supply hose in not vulnerable to gas or oil fumes , and the inside will not come apart or collapse over time? Most parts stores carry a specific type hose for vacuum applications, and the type I use is actually a 11/32" hydraulic hose size.
Also, if the master cylinder is properly bench bled and installed correctly, there is no need to bleed the wheel cylinders if the hydraulic system integrity was good at the start.
After a couple recent jobs, I have found the rear wheel cylinders started leaking after some miles. The master cylinder of a vac booster is different from a PM as it supplies more pressure to the rear shoes. The 25-26 year old wheel cylinders may not be up to the task of handling this increased load for very much longer?
dwall
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- May 25, 2001
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- 1,085
Great thread Mike (& Nick).
Got all the stuff you have in picture #1 and Casper's vacuum block. (The MC booster & master cylinder were the same as on 85 Regal parts car.)
Going vacuum on the 70K mile gray T. It has the never ending brake light which may be simple or complicated or expensive fix on the old Power Master. Its time for change. I liked the way the vacuum brakes handled on the old fart (that's old ME & of course my not so old dearly beloved) 86 T cruiser we had for a few years.
Bob
Got all the stuff you have in picture #1 and Casper's vacuum block. (The MC booster & master cylinder were the same as on 85 Regal parts car.)
Going vacuum on the 70K mile gray T. It has the never ending brake light which may be simple or complicated or expensive fix on the old Power Master. Its time for change. I liked the way the vacuum brakes handled on the old fart (that's old ME & of course my not so old dearly beloved) 86 T cruiser we had for a few years.
- With Nick's tip in mind I will hook up the booster & filter to the ported block with 11/32" hydraulic line. I assume the hose connectors for the metal vac lines can be just conventional vac hose (they look original) so I guess Ill replace them as long as things area apart.
- I'm thinking high boost applications need check valve only - not me or the missus.
- Wheel cylinders should also probably be replaced
Bob
ttypewhite
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- Oct 1, 2001
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- 4,156
The easiest thing for guys looking to run #6 AN fittings. Buy the same check valve I bought from Summit, take off your upper plenum, drill and tap the side of it ( above your fuel rail) with a 1/4NPT for a #6 AN fitting and run a run to it like I did using 2 - 90 degree fittings on a braided line and leave your vacuum block on the top of your plenum alone.
This seems to be the cleanest way of doing it. For now I'm going to route the lines off of the PCV and use the hose Nick recommended straight to the driver side vacuum port until I have time to tap into the upper plenum. My biggest concern with my vacuum setup is removing any chances for errors and routing the line straight to the vacuum source.
Just get the check valve I sent you with the barb fitting. But I think that size is wrong. 3/8 check valve with the barb fitting instead of an fitting. No need for that extra fitting.
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