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Carb sync tool, which to buy?

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Gotta get something to sync these things. I've done a ton of motorcycle carbs and used a vacuum gauge set. Can't with these, so is the $65 German one worth the extra $$$ or is the unisync the way to go?
 
kellysguy said:
Gotta get something to sync these things. I've done a ton of motorcycle carbs and used a vacuum gauge set. Can't with these, so is the $65 German one worth the extra $$$ or is the unisync the way to go?
Click to expand...


I can't answer your question, but I'd love to see the pictures and tales of fitting those carbs. I'm about finished with my engine rebuild and am thinking about carbs!
 
Still not on yet; ordering everything else I'll need at the moment.
 
I bought a UNISYN and it was no good. The old ones were decent but they've offshored them and the one I got (Made in China) had tolerances that were so bad that in order to flow enough air to get the bead to move, it choked off the engine. .. Now I have the one from GUNNSON, makes or the ColorTune.

One nice feature is that if you don't want to use the gauge, you can use the hose to listen for the hisssssssss...

NFI
YMMV
 
Somewhere in the past, I acquired some type of carb synchronizer. It is a half round stainless case about 3 feet long surrounding some glass scales. Unfortunately I picked it up right out of school almost 30 years ago, when I didnt have a use for it. Now I have no idea where it has been carefully stored in that safe place all these years. Something else I need to put on a list and keep an eye out for.

The last time I was surfing on this subject there were plenty of DIY pages for building one.
 
I have one of those crappy Uni-syns too. The float always sticks. The rubber hose method is actually pretty accurate. Don't knock it 'til you've tried it. I think there's an explanation of how to do it in the Bentley Manual, either in the main section or in the early cars owner's manual section.
 
I prefer using the gauge, but the rubber hose method is to put the one end of the hose to your ear and the other at the throat of the carb(s). Move the hose from one carb to the other and adjust until the hissssss sounds the same in both places...
 
I've had the same experience with a new Unisyn. It works fine on the Healey but doesn't on smaller engines like my MGTD. You can find older ones on eBay and they work fine. The older ones are easy to spot. They have the graduations on the plastic tube crudely painted on. The newer ones have the graduations molded in the plastic tube. The plastic tube on the old ones may actually be glass but I'm too lazy to go look right now.

All that being said, I used one of these at a friends garage and it is slick. If I buy another one, this is what I'll get. Didn't try it on a small engine but it seemed to be pretty sensitive.

https://tinyurl.com/2bc6mb6

Marv J
 
Tube on the old one here is plastic. ISTR it came from MG Mitten back in the late '60's. :wink:
 
I'm a big fan of the SU tool kit one with the wires that stick in the dampers. Then you can see the comparison at all throttle settings. The other bits in the kit are very helpful, too.

Highly recommended.

Peter C
 
Marv, that's the German one I spoke of. Moss has it for $65. What are your thoughts Doc?


Edit: Just found that one on ebay for $36 + $8 shipping. I might just go that route. I've got bad ears and eyes so I don't trust myself w/ the manual methods.
 
Just remebered, thatc one on ebay is made by "Latest Rage", who ships stuff to China to have it copied.
 
kellysguy said:
Marv, that's the German one I spoke of. Moss has it for $65. What are your thoughts Doc?
Click to expand...
That's the one I have. Seems to work fine on the Sprite, though I can't compare it to any others as it's the only one I've ever used.
 
I got an old unisyn off ebay and it worked fine, I was close with the hose and hiss method, closer with unisyn, probably still pretty bad tune by the pros standard but I think for a novice I did alright. I think I paid $25ish.
 
I have one of the newer unisys and it works fine. However, if you have a slight vacuum leak it will choke out the carb.
 
I just bought the one that is the one in the su tool kit. It is flat and has the flip up tube.I could not get it to not kill my engine. I can not see how to adjust it. I used a tube.
 
My Unisyn also came from MG Mitten. I still have their 1966 catalog that shows it selling for $9.95. Now I have to wait before I can use mine on my carbs. I just couldn't get them to adjust properly. Joe Curto has them and said the typical turn around time is six weeks. He has had mine for two weeks now. I hope he is as good as Hap says.
 
He's as good as we all say. I've relied on Curto for SU bits-n-pieces for decades.
 
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