[SOLVED]manometer vs gauge dials

[limax2]

To check the calibration of a four dial set-up I made an adapter to take the four pipes and a shut off tap at one end and fitted the other end to an empty co2 bottle from the mig welder. Then with some water in the bottle and the tap open I heated it up until steam came out, then shut the tap. As it cooled down the four gauges all measure the vacuum created by the cooling at the same time. I can't remember if I had to make some fine adjustment but I do remember they were very close to start with. 
If a photo is needed it will have to wait, because I am not about to do it right away. 

[keratos]

To check the calibration of a four dial set-up I made an adapter to take the four pipes and a shut off tap at one end and fitted the other end to an empty co2 bottle from the mig welder. Then with some water in the bottle and the tap open I heated it up until steam came out, then shut the tap. As it cooled down the four gauges all measure the vacuum created by the cooling at the same time. I can't remember if I had to make some fine adjustment but I do remember they were very close to start with. 
If a photo is needed it will have to wait, because I am not about to do it right away. 

Thanks. Regrettably I don't have much mechanicals tooling , more electrical for me. I certainly don't have welders or gas bottles. But thanks for the tips

[savvy]

I have used dial type both on my VFR (now gone)and fazer I used fishtank air 4 tube connector to balance them.Another post can't remember which off hand, but they worked well for me/
  PICS BELOW

[red98]

I have the same set as savvy, had them years and never give any trouble, calibrate by connecting to the same carb one at a time and adjust if needed using the silver screw at the bottom of the dial beneath the glass...

[keratos]

I have the same set as savvy, had them years and never give any trouble, calibrate by connecting to the same carb one at a time and adjust if needed using the silver screw at the bottom of the dial beneath the glass...

Done that , still jumping and sticking, calibrated using single pipe and noted deviations as per photo above. I guess they are just crap. What dya expect for £40. The Davida gauges are great but expensive for a one-shot task. Anyway, I've purchased - as highlighted in my post above - a Morgan Carbtune 4 port tuner for £30 2nd hand in great condition. See how this goes.

[andybesy]

I've been watching them for ages on ebay mate and at £30 for a Morgan Carbtune you got a good deal, going rate is about £45+. Good luck and let us know how you get on.

Andy

[keratos]

exactly.
well, they surely cant be worse than these gauges
I'll report back probably in a week or so after they arrive
in the meantime, when I balanced by carbs with the dials, I've realised that the calibration is probably out across all 4 gauges so they aint actually balanced at all. Not a problem with carbtune - they operate on different mechanics - vacuum pulling steel rods in a tube as opposed to mechanical dials uncalibrated

[Fazerider]

You can always check the sensitivities of the gauges match by shoving the hoses into a vacuum cleaner nozzle.
By the looks of it, you can probably adjust them if necessary.

[keratos]

nice pic. I'd opened one up years ago and got mercury all over the place - not a good idea. Refreshing to see that health and safety is paramount these days and we resort to big bolts and springs - good thinking  :think