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Hello everybody, the question is when checking if is running rich or lean, but when I raise one of them all the way up nothing happen with or with the vacuum install and the other would need to about 1/2 an inch. before it would stall. I have a video on Youtube under "67 Mini rough idle. If you take the time to view and is bad or not clear, I'll try to make another one or explain to as best I can.

P.S. the reason I didn't get back to the update with the '' Starting Up Problem" is because I took it to a shop and got the electrical problem solved and wouldn't go back again. I drove it for two months and ran great, all I did was changed the radiator fluid when it start running rough and I think all I have to do was check the choke cable because it might got stuck but it too late.

Thank you for taking the time for reading this and I hope you would view the You Tube under 67 Mini Rough idle. And Thank again Thai

Got a direct link, couldn't find it under "67 Mini Rough idle"........

You only have to lift the pistons about 1/32 of an inch......If you have to lift them further to get a response, somethin is not right.....

From just reading your post, sounds like semi major vacuum leak, but, need more info.......

The link is

https://www.youtube.com/watch?v=ep6HcjS ... e=youtu.be

OK, that worked......

Two possible reasons that front carb is unresponsive, one, the throttle disk is completely closed, or, there is no fuel in the jet (for various reasons)

The big lean flat spot when you open the throttle, could be because no1 carb is not letting fuel through, and, only no2 carb is working...

Start by, taking both dashpots and float bowl covers off, check both float bowls for fuel, and, check visually for fuel in both jets.....check that both lifting pins are nice and free......

Make sure both dashpots have springs in them, check needles are flush with the bottoms of the pistons, re assemble, and, top up dampers with engine oil.........

While everything is apart, check jet hight, and or, re set them both......screw both jets all the way up till flush, then, turn them both down 12 flats (two full turns) each.....this is a basic starting point....

Once all that is looked at/sorted, slacken off the two pinch bolts that connect the two throttle plates.....Start engine, and, adjust idle so each carb is doing half the work......takes a bit of fiddling back and forth to get them balanced.....you can use an airflow meter, I just hold a couple of fingers across the carb mouth, and, "feel" the airflow.......once this is done, you should be able to just open each throttle a small amount, and, the engine should speed up nice and evenly on either one.....You want to aim for (depending on cam etc) for a nice smooth idle at just under 1,000 rpm, 900 is a nice number....you may have to pull the timing back a bit to achieve this, depending on the shape of the rest of the engine etc.......

Now, you should be able to adjust the idle mixture. With the engine idling nicely, push up on the lifting pins, if rpm increases, carb is too rich (screw jet up to lean), if it immediately stumbles, or, stalls, it is too lean......screw jet down to richen.....on a good set of carbs on a good motor, you shouldn't need to go more than two flats at a time.......When set right, lifting the pins should give a slight rise in rpm, which should immediately drop right back.......All the above assumes you have reasonably correct needles....

Once all that is done, snug up the pinch bolts with about .012 clearance on the throttle levers.....

Do all that, and, report back.......

Thank you very much, I will try to understand only because I'm not too good with the manual and yours explanation. I'm a visual guy, maybe that's where the expression monkey see monkey do. It'll take sometime to sort this out. Thank again

I check the fuel supple lines and founded that one that goes to the #2 carb. pot was block and the plastic fuel filter was over tighten. I did the a drop test on the pods and the piston was switch. I ordered the Uni-Synch and oil and should be here on Saturday. I hope that's the only issue.
Frist I should synchronizer both carbs. then turn both jets all the way up, then turn them back two full turn and start adjusting the mixture with the vacuum disconnect?

Thank you very much for taking the time and advice, I'll report back on Sunday if it all work out.

I set both carbs. back to basic, screw both jets all the way up till flush, then, turn them both down 12 flats, now I try to synch after the engine is warm them with the Uni-Sync. The #1 carb would kill the engine and the other would give me a reading. When I try to check the piston on the #1 carb. I would need to lift about 1/2" to get a reaction and the #2 has no reaction at all. Have I miss something?

Thank You, Thai

Did you read what bwaminispeed told you above?

The fuel supple that goes to the #2 bowl was block and the plastic fuel filter was over tightened so fuel wasn't going to #2 carb. Dash pots was clean and springs are in tag with 321 oil. I just didn't check both float bowls for fuel, and, check visually for fuel in both jets. I start it today and ran better, just the Idle was high.

Hi bwaminispeed, the jet to the float bowl is disconnect, I try to remove the carbs. but having a hard time removing the #2 carb. because the clutch master cylinder is in the way, I try to removing the float bowl but no room to for screwdriver, would have another way? The picture show what's I'm talking about. Thank you