Help setting up triple carbs.

[flathead4rd]

Just got my three 97's back from Uncle Max. Great workmanship. I need to know where to start once they are hooked up. Will be running straight linkage on a 286 CI Merc engine with Potvin 415 Cam, etc, etc. My first question is about the idle mixture screws. Do I just use the ones on the center carb and close them on the end carbs or do they all need to be adjusted? The jet sizes and power valves have allready been determined by Max. I run an electric pump at 2-1/2 lbs. Thanks for your comments.

[Charlie ny]

4rd,
My inquiry would be to Uncle Max.....801 583 6169.
Charlie ny

[Walt Dupont--Me.]

4dr. There very easy, don't let them scare you. Straight linkage is the only way to go. The idle air screw all have to be adjusted the same. I'd start off with all screws open about 3/4 turn. it's easier if you have a Unasyc, they don't cost much, around 25 bucks, Speedway has them. Set the syc on top of each carb and ajust the throttle screw so the ball on the syc is in the middle. If you don't have one just take rubber hose and stick it into the top of the carb and the other end in your ear, You can hear the carb sucking air, try to set each carb the same, If it's idleing to fast back the stop screws back about where you want it. Now you can play with the idle air screws, screw each one in until the engine starts to die down and back it off just a wisker, do that to each carb. You'll get the nack of it with a little practice. Walt

[Ol' Ron]

Well it's obvious this isn't a street engine, however if it's going to run in traffic I'd run one carb untill I got the rest of the car sorted out. This will give you time to brake in the rings as well as how the car responds to drivability. After you get a coupla hundred miles you can putz with the carbs. Personally I'd use progressive, much kinder to the engine.

[flathead4rd]

Thanks for your replies and advice. This engine allready has about 2K miles on it. I dialed the center carb in minus the two outer carbs. Runs good, quick throttle response. I also have a Unisyn. Now the outer carbs are installed and other than synchronizing them first with the Unisyn, what do I do with the idle mixture screws? Some say close them off and others say use their idle circuits same as the center carb. What's the step by step proceedure for doing that? Thank's again for all your help.

[Mike in AZ]

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looks like Walt explained the idle mixture setup.....otherwise, I'd get back to Uncle Max who did your carbs and explain the situation....if you haven't already done so, of course.....i think he's set up a few multi-carb setups before....good luck....Mike

[3340]

what ol'ron said is the best way to go.

[Pete]

It's not rocket science.
Do it like Walt says.
Should take you about 5 minutes to adjust everything.

[Step-down]

4rd- The reason you here some folks say to close the front and back carb is on progressive linkage. The center would act as primary at idle. Your running straight linkage on a triple ,lots of carb at idle. I just went thru this with Max that's the only reason have anything to offer here. I'm happy be be corrected here .

[lonewolf]

The only time that you dont use the outer two carbs idle circuits is with progressive linkage..*

[Ol' Ron]

Running all three carbs at once, dumps allot of fuel into the engine through the accelorator pumps washing the cilinder walls with gas. Not the best, for ring life.