Brake Hoses

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Peter M. Zimmermann
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Brake Hoses

#1 Post by Peter M. Zimmermann »

Just finishing up an out-of-storage '58 A Model. Ran into a really weird problem when replacing the brake flex hoses. After installing my new front hoses, labeled "ATE" on their bag, I discovered during final inspection that the lines were tight as a bow string at full steering lock. After mulling this situation, calling alternate suppliers, and mulling some more, I took one back off the car. I discovered that the new "ATE" hose was made by "Flexitech," IN ITALY! I knew that Sierra Madre Collection states that their front hoses are supposed to be 410 mm long, so I measured my Flexitech. 385 mm (about 15.125" long). DARN!!! Now I'm trying to find a pair of original ATE hoses that are about 16.25" long. Yes, I can use a local hydraulic hose specialist who can re-make my two hoses, but then I would be forever responsible for the brake system on the car. I'm not ready to go that route yet.

Any suggestions/information regarding this issue would be greatly appreciated.

Brad Ripley
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Re: Brake Hoses

#2 Post by Brad Ripley »

Front brake hoses, A thru C, are all the same length, part number 644-42-311 See ATE drawing below.
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Peter M. Zimmermann
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Re: Brake Hoses

#3 Post by Peter M. Zimmermann »

Thanks, Brad! I think that I made a mistake. Those 385 mm front hoses might just be correct (and Sierra Madre's site has a glitch), and installed are tight with the suspension unloaded, but maybe are OK with the suspension loaded! Sierra Madre was very kind in doing a comparison with a different (aftermarket) hose, and I compared my new hose to the hose that was removed from the car. All measured the same, so I will put my two new 385 mm hoses on the car tomorrow, and check them at full lock with the suspension loaded. We'll see how it goes...

Brad Ripley
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Re: Brake Hoses

#4 Post by Brad Ripley »

On original ATE hoses, if you look carefully you may see the ATE number stamped in. In this case the ATE number is 24.5165-0350.3 With most ATE parts you will find the major dimension embedded in the part number -- 350 mm in this case, plus the fact in brake hoses the measurement is not overall but from the clip groove to clip groove.

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Thomas Sottile
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Re: Brake Hoses

#5 Post by Thomas Sottile »

always compare the old part to the new one.

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Peter M. Zimmermann
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Re: Brake Hoses

#6 Post by Peter M. Zimmermann »

Yep, I goofed! I failed to take into account the amount of difference between unloaded, and loaded, suspension. That said, I still think that the hoses are too tight at the unloaded position. For example, during lubrication a technician might have a tendency to swing the unloaded wheels to full lock while lubricating the front suspension. This will definitely put a level of strain on the tight hoses, and I feel that an additional 0.5" to 1.0" of length sure wouldn't hurt!

Thomas, great point! Although one needs to be careful regarding old parts, and if they were properly used, these cars are now about 60 years old and it's anyone's guess as to how many brake hoses have been on a car. I did, eventually, dig through the "old parts" parts bin, found the previous set of front hoses that were on this car and compared them. They measured the same, but the old hoses were deteriorated badly enough that the writing on them was obscured. Oh, well, bleed them next, and then go for a short, slow drive for the first time in about 14 years!

BTW; Sierra Madre has begun the process of correcting their web site in order to supply the correct hose dimensions.

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