I've just put on dual 97's and at the same time I bought a Uni-Syn Carb balancer to get them dialed in properly. The problem is I can't seem to get any reading from it. The little red plastic indicator in the tube is free to move, so its not stuck. When I use it I put the balancer on the top of the carb and as I wind the centre disc in, I get nothing until the engine eventually stalls because the hole is completely closed off! Am I doing something wrong? Have I got a broken one? Any suggestions?
Check for vac*** leaks. I've used them on sidedraft SU's as well as Strombergs and they work great to get a balance.
Where do you get one? I'm going to need one sooner or later. Will it work ok on a couple of single barrel Rochesters? Thanks, Jay
Vacuum leak on the car or the balancer? There isn't a vacuum leak on the engine, I know that for sure. Its shows no reading on both carbs. I got mine from Sacremento Vintage Ford, but I know Speedway does them and properly many more....
My experience was the same as yours. I have one buried in the bottom drawer of my tool box. I bought this one and it works like a dream. It's reading right above the 8. I don't know what the numbers represent CFMs? I just balance them until they both read the same at the idle speed I want. Others will swear by the Unisyn I swore at mine. good luck.
You guys are using hi tech tools, I just use a piece of rubber hose and stick it in the throat of the carb and the other end in my ear, when they are balanced you will hear it. Been doing this for many years on MGA's and my plymouth with duals. Works great.
I guess it's possible you may have a vacuum leak between the base and the upright part where they go together. Can you put a vacuum directly to the hole that's in the venturi part of the tool to see if the "red floater" moves? There's a small hole in the round plate right at the inner edge, stick a vacuum hose from the running engine right over that hole to see if it moves. God can't get two fingerprints the same, anything made by man can be faulty too! Or stick it on the hose of your shop vac, that should peg the thing. That part that swivels to different positions, possibly it leaks at the join. They do tend to "choke" the air flow to the carb, but it should read something before killing it. On mine, (I use it on the SUs on my MGB GT,) I only expect it to draw, and only screw the plate down far enough to draw the red thing to the first mark in the tube. Make sure the tool plate is making complete contact to the carb neck. Test the tool!
there is this thread in the Tech Archives, CARBURETOR, carb syncing, how? http://www.jalopyjournal.com/forum/showthread.php?t=3448 you may find something useful there.. Paul
There is another possibiliy. Did you try it on both carbs? When I adjusted the 97s on the 34 with the Holley, I got no reading on one carb and obviously a higher reading on the other carb. The reading went up as I adjusted them. The truck was runnig fine even though the carbs were way out of sync. With a small CI engine and 2 carbs, an out of sync carb may not have enough velocity to get a reading. Mine didn't until they got close.
That's exactly correct. High Tech Garden Hose! I've done this on SUs, Amils and 97s. Alawys works, when I told my limey lovin' buddies I bought a Uni-Syn, they laughed at me and made me buy a round of Guinness's. Then they tried to sell me a length of hose and called it an organic Uni-Syn.
I know, I can't tell you how many times I 've been laughed at but it works, I have been doing this for about twenty years and it works on bikes and cars, try it you will be amazed.
Thanks for the info guys. I had a play with it and can get it to work by using a drink straw, so I know it works, just not on the car! I've had it on both carbs and its the same, nothing! I can't see it being the choke holes leaking air as you would be able to compensate for it, if it did leak air with the adjustable disc. Spoke to a guy and he told me that all the balancer's are a waste of time and all you need is a length of hose, I'm beginning to think he's right...
My hearing is ****, all I could hear was my engine running when I tried to balance the SU's on my 100E with a hose. I bought a balancer from the same people that make Colourtunes, (is it Gunson?). Basically it's a plastic version of the one you've got and it worked a treat. I took it to a rolling road for a proper set-up a little while afterwards and the guy said it was nearly spot-on. Only cost about a tenner. Clark, have I told you that Belcher's have got my block?
Inserts & full pressure to go with the counterweighted and crossdrilled crank and lightened flywheel. May not be ready for the first drags (I'll be racing the 100E in it's place) but it'll certainly be ready for September.
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