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Remote Vacuum Servo

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M

MiamiSprite

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I purchased a powertune remote vacuum servo unit for single line braking systems for my 62 Sprite (948) with disc brakes at front. Brakes work well but want to give my left leg a break.

I was planning on installing it this weekend and figured I'd read the instructions. First thing I noticed is that the two brakes lines supplied ARE DIFFERENT:

Short Line: 3/8"x24UNF Nut with DIN Flare, both ends
Long Line: 10mmx1 Metric Nut with Bubble Flare, both ends

Instrcution show one line from brake M/C to Servo and one from Servo to 3-Way adapter. Unfortunately it does not specify which line to use where.

Assuming the lines supplied are correct, then I'm expecting that when I disconnect the (existing) line from the M/C to the 3-Way adapter that one end will be 3/8" (3-Way?) and the other 10mm (M/C?). Or the lines supplied are wrong. My fear is with crossthreading the Servo (since I will know the threads for the M/C and 3-Way when I remove the existing line).

Anyone have experience with this?

Thanks!

Carlos
 
What are the threads on the unit itself? The threads on the T and MC are 3/8-24 and use bubble flares.
 
Trevor: That is sort of my problem, I realy can't get the gage in to see if the threads match the 24 TPI or 1.0 metric.

Don: The first are female and the lines have male nuts.
 
MiamiSprite said:
Trevor: That is sort of my problem, I realy can't get the gage in to see if the threads match the 24 TPI or 1.0 metric.
Click to expand...

Buy 2 bolts from a hardware store the size and thread that you need, and use them as your thread gauges. :thumbsup:
 
Roger said:
I think you should stop immediately!
LEFT leg? :nonod:
Click to expand...

I noticed the "left leg" comment as well. Right = Brake & Accelerator.

As above, buy a clean 3/8-24 bolt to check the threads in the fittings. You are not likely to find an M10x1 bolt a hardware store. However, 10mm is so much larger than the 3/8" that the bolt will be VERY loose in a hole tapped M10x1.

Also as stated above, you are likely to find all the brake line threads on your car are 3/8". I know that on later Minis they started introducing some of the M10 fittings.

If you have to source adapters or different brake lines I believe Summit Racing carried some of those components in M10.
 
Thanks to all. Will do as suggested and try the 3/8-24 bolt. I was surprised that they inlcuded the line with metric fittings. And yes, the minis have mixed fittings (found this on my 80 mini).

I will likely end up making new lines using copper/nickel pipes and my new flaring tool (K Tool 70081 - Brake Pipe Flaring Tool Kit).

Thanks Again to all. It's great to be able to get input from others.

Carlos

p.s.guess now I'll be refered to as Mr. 2-Right Legs :lol:
 
Have been working on my mini so I have not made much progress on this. I did decided to remove the blower/fan to make room for the Servo. But before installing, I'll touch up the paint. Hope to post some pictures soon.
 
What size is your master cylinder's brake diameter? I'm asking as I have changed mine to a 3/4" with my disk brake change and never really felt the need for the servo. On another car I've driven the m/c was left at 7/8 and with disk brakes in front you really need have a firm right foot.

I guess I'm trying to say I would rather get the hydraulics right on a car this light before adding complexity of a servo with added failure points.
 
The P/O repalced drums with disc up front but kept the 7/8 m/c. I suspect if I would have gone to a 3/4 m/c it would have fixed the problem. At the time I could not find a 3/4 m/c and did not want to send out to re-sleeve. Now I see that MOSS came out with a 3/4 m/c.

I finally got to it last Thursday and installed the brake booster. I started working on it at ~ 10 am and was done by 5 pm (lots of breaks, very hot day). It was not as difficult as I figured. The most difficult part was removing the carbs and manifold to drill and tap vacuum connection and figuring out where and how to mount. The latter was difficult only becuase I decided that no holes would be drilled (leaving me to use existing holes) so I could reverse with no need to weld holes shut.

Turns out that one of the lines (Long Line) suplied with the kit (with metric flares) was wrong. No problem because I only needed one line and made my own.

Now I have brakes. Made a huge difference. The car is much funner to drive.

Now I'm wondering how much better it would be if I replace the 7/8 m/c with a 3/4 m/c.

[image]https://i1258.photobucket.com/albums/ii531/hernaci/Sprite1/Brake_Booster_006.jpg[image]
[image]https://i1258.photobucket.com/albums/ii531/hernaci/Sprite1/Brake_Booster_001.jpg[image]
[image]https://i1258.photobucket.com/albums/ii531/hernaci/Sprite1/Brake_Booster_002.jpg[image]
[image]https://i1258.photobucket.com/albums/ii531/hernaci/Sprite1/Brake_Booster_003.jpg[image]
[image]https://i1258.photobucket.com/albums/ii531/hernaci/Sprite1/Brake_Booster_004.jpg[image]
[image]https://i1258.photobucket.com/albums/ii531/hernaci/Sprite1/Brake_Booster_005.jpg[image]
OK - still having trouble with images.
 
Here ya go! You just needed to close with a [/image] at the end of the URL instead of an [image].
MiamiSprite's images:
Brake_Booster_006.jpg

Brake_Booster_001.jpg

Brake_Booster_002.jpg

Brake_Booster_003.jpg

Brake_Booster_004.jpg

Brake_Booster_005.jpg
 
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