72 stock carb rebuild

thomas · Post by **thomas** » Wed Dec 24, 2008 11:22 am

I have everything cleaned up and ready to go. From 3 sets I hop to get 1 complete with possibly a decent back up. I am ready Ratwell site and he talks about setting the throttle plate openings with round feeler guages. The guys at advance look at me sideways. What should I use instead? Any other words of advice before I start the rebuild?

Post by **Amskeptic** » Wed Dec 24, 2008 2:41 pm

thomas wrote:I have everything cleaned up and ready to go. From 3 sets I hop to get 1 complete with possibly a decent back up. I am ready Ratwell site and he talks about setting the throttle plate openings with round feeler guages. The guys at advance look at me sideways. What should I use instead? Any other words of advice before I start the rebuild?

Adjust the throttle plate stops with this tried-and-true method. Back away the stop screw until you just see daylight. Bring it back so it just touches. Add 1/4 turn maybe 3/8. That'll do you. Somewhere I have a dual carb article that will help you set these carbs up. Maybe I should write a new one with pictures. . .
Colin

Dr. Scott · Post by **Dr. Scott** » Sat Jan 10, 2009 11:48 am

Thomas and I are trying to measure the output of the accelator pump...
reading the bentley it talks about putting a hose on the discharge end of the accelator pump injector...how? Carb off - we know...hose straight down? Throttle plate in the way, right?
We think we can get float level measurements right...of course we'll...14cc = .4 or so ounces? making my head hurt..

Post by **Amskeptic** » Sat Jan 10, 2009 10:17 pm

Dr. Scott wrote:Thomas and I are trying to measure the output of the accelator pump...
reading the bentley it talks about putting a hose on the discharge end of the accelator pump injector...how? Carb off - we know...hose straight down? Throttle plate in the way, right?
We think we can get float level measurements right...of course we'll...14cc = .4 or so ounces? making my head hurt..

I don't bother with measuring the stroke with the older carbs. Just put the cotter pin in the middle hole. Drive.

The later carbs with the threaded adjustment, well you have to suffer through the measurement process. Would thin aquarium tubing allow the discharge to get around the throttle plate?
Colin

thomas · Post by **thomas** » Sun Jan 11, 2009 6:02 am

Took the throttle plates off and used a straw. Worked perfect. Finally got 10 squirts to about 6.5 cc. I am guessing slow squirts because the quick squirts got as low as 4cc. To get the values on left and rght the same. Had to put one in the center hole and one in the outer. So should we just use center on both?

Float level. Have to remove the washer under float valve to get an value within range. Will triplecheck al measurements today but is the washer asolutely neccesary?

Gotta say I have wanted to run original carbs on my72 for a long time and am enjoying the challenge. Then can you jet same carbs for a two liter? Thats another dream.

Dr. Scott · Post by **Dr. Scott** » Sun Jan 11, 2009 6:50 am

1 down (maybe)...1 to go (I hope)...

Post by **Amskeptic** » Sun Jan 11, 2009 9:09 am

Anyone with dual carbs who wants to drive my car, feel free. They are excellent carburetors. Smooth driveability rivalling fuel injection, 22 mpg with a lot of high speed freeway driving, the only complaint I have is that the cold idle is sometimes too fast after the car has warmed up a bit. I have had these carbs since I was 19 years old, and I am now 49.
Colin

thomas · Post by **thomas** » Mon Jan 12, 2009 9:26 am

Thanks Colin. Its the confidence of people like you that have inspired me to keep it Stock and stuggle through the learning!

thomas · Post by **thomas** » Sun Jan 18, 2009 10:57 am

Throttle shaft bushings are pretty worn. I am thinking I can get a 5/16" bushing from ace and open it up .005 witha file. Doing a test I was able to get it where I can just barely see daylight. Much better than the busing I took out. Is it worth the time and effort or should I just get a machine shop to rebush? How much tolerance is there? Colin?

Post by **Amskeptic** » Sun Jan 18, 2009 2:38 pm

thomas wrote:Throttle shaft bushings are pretty worn. I am thinking I can get a 5/16" bushing from ace and open it up .005 witha file. Doing a test I was able to get it where I can just barely see daylight. Much better than the busing I took out. Is it worth the time and effort or should I just get a machine shop to rebush? How much tolerance is there? Colin?

The only tolerance you need is the tolerance required for smooth action. If you can hand-ream to fit, that would be . . . capital, chap. The outer diameter of the bushing fit in the throttle body needs to be slightly interference. I paid $25.00US the last time I bushed back in 1986.
Colin

keifernet · Post by **keifernet** » Thu Jan 29, 2009 9:04 pm

If you did not get them rebushed yet you could send them to me...just the plates taken off the carbs. I do them.

Itinerant Air-Cooled

Itinerant Air-Cooled

72 stock carb rebuild

72 stock carb rebuild

Re: 72 stock carb rebuild