Firstly, check your gauges. Swap the one with the higher reading with one of the others as see if you get the same reading. If not the gauge is out of calibration or naff. Many on the cheaper gauges can't be calibrated, in which case, as long as it reads the same constantly, you just deduct the error.
Once you've sorted the above out, balance 1&2 then 3&4 then bring 1/2 & 3/4 in balance by adjusting the middle
Looks odd to me Graham. What are the grey angled things with a threaded cap on them? And then another angled piece further along the pipe?
It looks like the left ones and not connected to the correct pipes
I hooked them all up to #1 cylinder to check how much (if any) they were off from each other.
The problem is that, no matter how much I change the screws, I get very little movement on the needles. What I might do next is try increasing the idle speed, then turn all the screws down until it's almost on the verge of stalling. Hopefully with the screws right in, any adjustments would be more noticeable.
Quote from: unfazed on 22 June 2020, 09:14:52 pmIt looks like the left ones and not connected to the correct pipes Well, unless there's another two short hoses on that side with stopper plugs in them which pull a vacuum when attached to the gauges...!
You can calibrate these. With nothing connected, take of the lens and adjust the brass screw until all the gauges read the same. Once all "zeroed" you should try them all on the same cylinder to check the reading is roughly the same on each gauge. Once done, you can connect to the other cylinders to confirm if the cylinders are out of adjustment or not.
Quote from: Grahamm on 22 June 2020, 08:36:47 pmI hooked them all up to #1 cylinder to check how much (if any) they were off from each other.If you telling me that every gauge gave a different reading when hooked up to No1?If that is the case and all the connections are good, the gauges are unusable. Sorry to say that but if they can't all read within about 0.1Hg of each other on the same cylinder, you've got no chance unless you can calibrate them within 0.1Hg.
Any I saw and/or worked on had the pipes coming straight from the front by the frame. Have you relocated yours?
When you swap the hose of guage on 2 to position I and 1 too 2 I presume it then shows the same as the others around 9?
Was the engine running rough that you decided to check the throttle bodies?
If you look at my pictures, you'll see that I wrote down the differences between the readings. So gauges #1 and #3 gave the same readings, but #2 was 0.75 down and #4 was +1 up.As long as I remember to add or subtract as required, I can get an accurate result.A mercury gauge is around £100 or there are digital ones for £400+ !