Author Topic: How I made carb vacuum adapters  (Read 4872 times)

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Offline Cannibal

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How I made carb vacuum adapters
« on: July 27, 2008, 02:24:15 PM »
I found some 3/16-3/16 double barbed fittings at Home Depot because California Sport Touring has been out of adapters for like 2 months (that reminds me, I need to call for a refund), and NEEDED and alternative. Here's how I modified 4 of these to make vacuum fittings to sync my carbs.

First, I wrapped one end with a couple wraps electrical tape so they didn't get all scared up from the drill chuck. I chucked that end up and spun it and using a hack saw, cut all but the last 2 barbs off (actually, only 1 barb left, plus the one against the shoulder in the center, so 2 "sections" were left).

I spun it up again in the drill and took a hand file and filed it until it was 5mm. After that, I took my 5x.8 die and threaded it. Then touched up the end threads with the file (45* angle) and spin again to give a light taper. I took a 5/16 drill bit and de-burred the cut end, then ran a pipe cleaner through to clean out the debris.

Unchucked it, removed the tape and threw an o-ring on, then installed them. They worked like a charm. Of course, my carb sync has 3/16" tubing on it, so they fit great.

Package:


Chuck it up:


Sorry, no pic of it cut off, but cut all but 2 "sections" of it off before filing it to 5mm (less material to file, and one of the barbs gives a nice place to rest the hack saw blade).

File it:


Thread it:


Clean it, o-ring it:


Install it:


Sorry for the crappy pics, a photographer I am not. But you get the idea.

Steve

« Last Edit: July 27, 2008, 02:27:51 PM by Cannibal »

Offline bwaller

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Re: How I made carb vacuum adapters
« Reply #1 on: July 27, 2008, 05:00:32 PM »
It's a bit of a stretch to those inside carbs, but good job Steve.

Offline rbmgf7

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Re: How I made carb vacuum adapters
« Reply #2 on: July 27, 2008, 05:05:34 PM »
as a guiness commerical would say "brilliant!"

lol, cordless drill a.k.a. the mini portable lathe. i've used my drill for similar situations  :D

Offline mystic_1

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Re: How I made carb vacuum adapters
« Reply #3 on: July 27, 2008, 06:25:30 PM »
Nicely done.

mystic_1
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Offline Cannibal

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Re: How I made carb vacuum adapters
« Reply #4 on: July 27, 2008, 09:26:16 PM »
Thanks guys. I know others one here have asked how to make some, so I thought I'd post this up.

The inner ones aren't that bad. The tubing I'm using is the clear stuff, but not the fish tank stuff, that's way thin. This has a pretty heavy wall and I'm able to just push it right on the inner ones. They are a bit tough to thread in, but I wrapped some Teflon tape around them to seal and installed them permanently. Since they really aren't seen, I figured no body would even notice, unless they were looking for them. They have a black vacuum cap on them, so they are sort of "camouflage".

Steve

Offline jason teamshralp

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Re: How I made carb vacuum adapters
« Reply #5 on: July 27, 2008, 09:59:28 PM »
as a guiness commerical would say "brilliant!"

I thought the exact same thing when I saw this.

Offline chrislib

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Re: How I made carb vacuum adapters
« Reply #6 on: July 28, 2008, 08:29:53 AM »
Nice fab work! Here`s a trick for getting the adaptors on the inside carbs, I take a t-15 torx driver and fit it into the end of the adapter, depending on the inside dia of your particular adapters you may need a different sized torx (t10 or t20 perhaps). Oh, my synch tool is a motion-pro.

Chris...closet Idlefiddler
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Offline JimHanus

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Re: How I made carb vacuum adapters
« Reply #7 on: May 24, 2013, 12:47:44 PM »
Nice idea, but how do you keep from dropping the cut off piece under the workbench? Should have bought 2.  :'(

Offline flybox1

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Re: How I made carb vacuum adapters
« Reply #8 on: May 24, 2013, 12:56:53 PM »
nice work steve, with felt washers and rubber caps, you can leave them in  ;)
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Offline 70CB750

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Re: How I made carb vacuum adapters
« Reply #9 on: May 24, 2013, 01:00:57 PM »
Ingenious!
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Offline Vinhead1957

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Re: How I made carb vacuum adapters
« Reply #10 on: May 24, 2013, 04:50:24 PM »
Great idea! Thanks for sharing

Offline BobbyR

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Re: How I made carb vacuum adapters
« Reply #11 on: May 24, 2013, 07:31:45 PM »
Very clever
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Offline ncstatecamp

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Re: How I made carb vacuum adapters
« Reply #12 on: June 07, 2013, 05:04:29 PM »
just a heads up, you can get adapter from amazon for pretty cheap (free shipping if you have prime) http://www.amazon.com/Motion-Pro-08-0013-Carburetor-Adapter/dp/B000OO4PVM