Brake Booster hose connection

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brotherhay
Posts: 59
Joined: Fri Apr 17, 2009 11:40 am

Brake Booster hose connection

Post by brotherhay » Mon Jul 09, 2018 8:08 pm

Its time to start tuning the '80 528i, but first things first, fix the vacuum leaks. Well, I can hear one very clearly after shutting off the car. Maybe you guessed it, but its the hose connection to the brake booster.

It looks like an L-shaped check valve of sorts, I cannot find this part anywhere.

Id rather not just caulk the thing up like an idiot, id love to replace the hose, check valve, and whatever that connector is that mates the hose to the Brake Booster.

Someone will answer this faster than I can find that part, and Ive already been lookin.

PatinaBeforePolish
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Location: Baltimore, Md.

Re: Brake Booster hose connection

Post by PatinaBeforePolish » Mon Jul 09, 2018 8:22 pm

I don't believe the L shaped connecter at the boost canister is a one way valve. I replaced #9 in the diagram and used the OEM hose, #6. Both are available from the dealer. Not cheap, but the OEM hose retains its shape even when hot. I also believe the one way valves go bad. My booster had oily water it it by drawing from the intake manifold through the bad valve after the engine was shut off.

https://www.realoem.com/bmw/enUS/showpa ... Id=34_0293
78 F150
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81 528i parts car
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brotherhay
Posts: 59
Joined: Fri Apr 17, 2009 11:40 am

Re: Brake Booster hose connection

Post by brotherhay » Mon Jul 09, 2018 9:25 pm

I bookmarked that site right away.... I had been there before, but that will really help in the future.

Got a camera in on the connection that I spoke of, which is #3 on the parts list. When looking close at the pic, I can tell the culprit is #2. I can see that its split as well as not seated properly.

Ill have to see if I can pop that thing off there and see how the connector looks also. Looks like it unscrews 1/3rd turn, then out, hopefully...

Thanks bud

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CabbageFumes
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Re: Brake Booster hose connection

Post by CabbageFumes » Sun Jul 15, 2018 6:45 pm

brotherhay wrote:
Mon Jul 09, 2018 9:25 pm
I bookmarked that site right away.... I had been there before, but that will really help in the future.

Got a camera in on the connection that I spoke of, which is #3 on the parts list. When looking close at the pic, I can tell the culprit is #2. I can see that its split as well as not seated properly.

Ill have to see if I can pop that thing off there and see how the connector looks also. Looks like it unscrews 1/3rd turn, then out, hopefully...

Thanks bud
Wishful thinking.
The plastic elbow is held in by a barbed connection- push fit into the rubber grommet (2&3).
You need to do the same thing everyone else does in your position: buy the correct vacuum hose, replace the check valve, replace the grommet on the booster, and reuse the elbow, unless it’s compromised somehow. All of it is available, and it’s shared by many different chassis throughout the 70s-80s. Just don’t break it when you pull it from the booster, which happens.
Fiver 12/73
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i3 8/14

brotherhay
Posts: 59
Joined: Fri Apr 17, 2009 11:40 am

Re: Brake Booster hose connection

Post by brotherhay » Wed Jul 25, 2018 6:24 pm

so to get that elbow off of there, just pull directly out?

I heeded the advice, new hose, check valve but no grommet just yet. was hoping I can find one locally rather than spend $10 to have one shipped

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CabbageFumes
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Re: Brake Booster hose connection

Post by CabbageFumes » Wed Jul 25, 2018 7:20 pm

brotherhay wrote:
Wed Jul 25, 2018 6:24 pm
so to get that elbow off of there, just pull directly out?

I heeded the advice, new hose, check valve but no grommet just yet. was hoping I can find one locally rather than spend $10 to have one shipped
It’s tight but yes it pulls straight out.
Fiver 12/73
Fiver 06/87
Sixteen-O-Two-er 11/69
i3 8/14

brotherhay
Posts: 59
Joined: Fri Apr 17, 2009 11:40 am

Re: Brake Booster hose connection

Post by brotherhay » Wed Jul 25, 2018 7:32 pm

You aint kiddin its tight!

Pliers underneath, and a long flathead behind it to try and help, and yeah, it spins a little but doesnt want to budge.

Im sure ill get it, just dont want to break that elbow.

brotherhay
Posts: 59
Joined: Fri Apr 17, 2009 11:40 am

Re: Brake Booster hose connection

Post by brotherhay » Sun Aug 12, 2018 7:11 pm

CabbageFumes wrote:
Wed Jul 25, 2018 7:20 pm
brotherhay wrote:
Wed Jul 25, 2018 6:24 pm
so to get that elbow off of there, just pull directly out?

I heeded the advice, new hose, check valve but no grommet just yet. was hoping I can find one locally rather than spend $10 to have one shipped
It’s tight but yes it pulls straight out.
well, I got this thing out, pulling straight out. It didnt go so well.

The elbow is for sure tabbed as mentioned previously in this post. I took that as more like a barbed end, and would just pull out of a grommet. Not correct. I shouldve cut the hose off just above the elbow. It feels like theres nothing but pressure holding it on. I suspect a 1/3 turn in either direction and it wouldve just fell out.

Im not sure theres any way to even rebuild the tabs that were on the elbow, but I might just try. 2 sheared off, totally lost.

I would for sure cut the hose off and twist that elbow before doing any kind of pulling on it, thats for sure.

I suspect different boosters revisions was the issue here. I see a mention above of a grommet to pull it out of. I also see that as parts listed for this booster elsewhere, but this was not of that type.

The elbow for this turn in model seems pretty easily found, and only $20 shipped. So I got right over it.

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