*** Brake Boost Isn't! ***

[mgburg]

I have an interesting issue with the brake booster on my 450SLC.

I "bumped" this little plastic "disc" that looks like a mini-filter/flow controller that is near the brake booster and brake master cylinder. There are two hoses, about 1/4" I.D. that attach to this thing...well...one side broke off. That side is "sucking" while the engine is running. Well...now I have to press the brake pedal like a SOB to stop the car.

Q.: Can I "bypass" this little plastic "unit" with a "splice" piece of hosing 'til I get the right stuff? I'll see if I can get a cellphone shot of the piece in the morning. BTW: The two hoses seem VERY STIFF and brittle. I'm thinking I should replace the whole length but I'm not sure if the line was suppose to have a bit of stiffness to it or not. I'm wondering if a nice piece of fuel line would work just as well, if not better.

Any recommendations folks?

TanQ!

[Deltacom]

Seems the vacuum check valve is broken and it is a very necessary item to function properly. I wouldn’t look for short cuts when it comes to the brakes!!

Would suggest to replace the unit asap. Part number A1074301329. See this item 330478001044 on ebay.

There are 3 types on Fastlane for your model

[rowdie]

I think you have a typo there. 1074301329 should be 1529. Different number before chassis number 011199 fed or 011190 ca.

I agree, don't mess with this. New entire assembly ASAP.

[Deltacom]

Originally Posted by rowdie

I think you have a typo there. 1074301329 should be 1529. Different number before chassis number 011199 fed or 011190 ca.

I agree, don't mess with this. New entire assembly ASAP.

You might be right Rowdie, the EPC is not always correct. I found many part numbers does not correspond..

[RadioTek]

To put it simply, that hose is the vacuum supply for the booster for your brakes. The check valve is plastic, and age, heat, and ultraviolet light degrade plastics. You could put in a splice, and get it to work, but it wouldn't hold the vacuum when the engine is off. You would have no brakes unless the engine was running.

You're ahead of the game by far to get a whole new assembly. The cost isn't that expensive, and you will have new, CORRECT pieces in a critical system (the Brakes). When this happened to me on a 124 many years ago, it took less than half an hour to do the job. Including getting the tools together and washing up after.

Some things you REALLY don't want to "cheap out" on. This is one of them.

Good luck.
Scott

[rowdie]

I was wrong as I was looking at an SL. Then The part number with the 13 in it came up part not found on XXXX so I ass u me d it was wrong.
Ooops. Sorry.

[mgburg]

Thanks guys...I called the local dealer and with the correct body/engine numbers, he got the right part ordered and should be here on Tuesday for a whopping 53.00USD (plus tax...no shipping...he had other parts coming in from Fontana).

I did "fix" the item...almost a full roll of 3M 33+ and a few cable ties...I tried finding some heat-shrink that would go over the whole mess but I couldn't locate some large enough...the key to the whole thing is watch your speed, and brake only when you really need to...tapping on them seems to "bleed off" the vacuum a little too soon.

For a sporty little car ( ), I'm driving the thing like I'm carrying a 40y.o. bottle of nitroglycerin between my legs!

Good luck to me and the funny pages!

Thanks guys!

[mgburg]

Here's a followup...

The part arrived...the REAL part # turned out to be the following: A 107 430 06 29 and is listed as: Line, Brake Booster. With tax (5.5%) it came to $58.24. It was a direct swap with the old line, although a "touch" shorter in overall length.

And as I suspected, the older line may have had a crack/leak in it because I can lay on the brakes and I'll have to apologize to my reflection, in the mirror, for giving myself a "steering wheel rub" on the forehead.

Again, thanks to everyone for the assistance...

[RadioTek]

I love the report of a good fix for a problem,!!!

Thumbs up and congratulations.