1982 W123, brake booster main vacuum line, no long being produced??

[gregp1962]

WHat are we doing about this part no longer being available. My problem is that the small vacuum tube nipples became brittle and broke off. (red arrow) I'm assuming that the diaphragm looking thing next to the small nipples is a one way vacuum valve. could a substitute set up be created?

[imgolden]

There's a person on Facebook that has started to manufacture these new. I believe he has them on Ebay now too. They aren't cheap, but this is such a critical part and they look well made.

[gregp1962]

Is that just a generic vacuum check valve next to the two small nipples? (To the left of the red arrow)

[ykobayashi]

I just went out to check mine and it broke when I touched it.

[skeppa12]

Mine is broken as well.
I did use some glue for a temporary fix however would love to replace it with a quality product.

About half way down the page, although it isn't cheap:
https://www.dieselgiant.com/vacuumsystemrelated.htm

[gregp1962]

Originally Posted by ykobayashi

I just went out to check mine and it broke when I touched it.

This is the story of our lives with this brittle part. If that is just a general check valve, then I think we'll have to get used to using rather large diameter check valve in conjunction with other vacuum parts to connect it to everything.

[Jareb]

I'm pretty sure I have a MB NOS one in my parts stash....I'd have to check to be sure.

[gregp1962]

Originally Posted by Jareb

I'm pretty sure I have a MB NOS one in my parts stash....I'd have to check to be sure.

Do you know if that's a regular vacuum check valve?

[Junkman]

See if any of the 126 parts are still available. Nipples would be in a different place and length may be different but modifications could be made.

JB Plastic weld connects broken plastic where the joint is stronger than the original plastic. About $5 on Amazon.

[ykobayashi]

I Superglued the nipple back on to hold it in place. Then I put a good filet of jb weld on it to secure it. All last night.

It looks pretty solid now. I put my vacuum line back on.

My understanding is it’s a check valve. One little nipple that goes to the locks and reservoir is from the main line and the other nipple has an orifice for the transmission vacuum control valve.

When I went to look at mine last night I realized I had them switched. Must have been hasty assembling it. When I tried to take off the rubber vacuum hose it went “snap”. There’s little cracks all over mine. It was bound to happen eventually.

I put jb weld on the good side too just to secure it preemptively. Probably a smart thing to do before it breaks.

[Jareb]

Originally Posted by gregp1962

Do you know if that's a regular vacuum check valve?

Yes, that is the vacuum check valve for the line.

[Diesel911]

Originally Posted by gregp1962

Is that just a generic vacuum check valve next to the two small nipples? (To the left of the red arrow)

Yes, several years ago I bought both some plastic and aluminum bodied check valves on eBay. Not actually expensive.

Since it is the little nipples that break you can assemble those from brass fittings. Tha could cost a bit, but they would last for ever.

I replaced the plastic line with regular vacuum hose a long time ago using the old steel end fittings. Making it longer allowed me to run the line further over the top of the fender well.

[Diesel911]

Here are the other parts you would need and the pic is from an ebay seller.

These a check valve and rubber hose.

[BradenFinney]

One thing I worried -slightly- about when repairing mine with random hard plastic and epoxy was the nature of the orifice size.

The piece is just a check valve, but the two "discharge" lines have different inner diameters. I actually repaired one of my "discharges" by overdrilling the hole and squeezing a small orifice connector that was used to join the two y connectors further down the line.

It is my understanding that the orifices were put there by design to limit the quantity of vacuum to appropriate parts... With all of the leaks on these cars now (however so small) not sure how likely the system is to operate exactly as designed with proper flow rates.

[5cylinder]

Originally Posted by BradenFinney

One thing I worried -slightly- about when repairing mine with random hard plastic and epoxy was the nature of the orifice size. It is my understanding that the orifices were put there by design to limit the quantity of vacuum to appropriate parts.

If some brave soul with a good line intact is willing...
Remove each line, one at a time, hook up a vacuum gauge, run the engine, and report back the reading.

Originally Posted by BradenFinney

With all of the leaks on these cars now (however so small) not sure how likely the system is to operate exactly as designed with proper flow rates.

A realistic assessment.