Mazda Rotary Club

General => General Technical => Topic started by: m1tch on March 20, 2010, 02:38:55 PM

Title: Boost gauge calibration?
Post by: m1tch on March 20, 2010, 02:38:55 PM
Hi everyone, just bought a used boost gauge from the Atomic rex clearout - thanks for getting it to me! I have just spent an hour in the rain getting it all fitted and plumbed in and the gauged mounted where I wanted it.

Basically the gauge doesn\'t read 0 when it is open to air, here is the gauge photo from the for sale thread how it was sold:

(http://www.atomicrex.co.uk/downloads/Secondhand/2010-01-06/IMG_0523.JPG)

How can I calibrate the gauge to be at 0 in air? I have just gone on boost and its no where near where it should be :(

Can anyone help?
Title: Boost gauge calibration?
Post by: TiddlesRX7 on March 20, 2010, 03:15:07 PM
Can you get into the guage at all? If you can you may be able to just move the scale around so that the needle sits on zero. Either that or move the needle to zero.
Title: Boost gauge calibration?
Post by: m1tch on March 20, 2010, 04:01:59 PM
As far as I can see it is sealed, no screws or anything on the back :(
Title: Boost gauge calibration?
Post by: AtomicRex on March 20, 2010, 06:04:28 PM
Hey Dave,
 
Just picked up your PM....if it doesnt work I will give you a refund :)  It worked when I took it out of the car....its just been sat there for the last couple of years.
 
Let me know what you want to do :)
Title: Boost gauge calibration?
Post by: m1tch on March 20, 2010, 07:13:39 PM
I will have a check tomorrow, I will unscrew the vac line, sometimes there is a screw thread to calibrate it there, I will have a look tomorrow and see if its salvageable, just a bit frustrating as I took a while to sort out the mass of wires and things and set it up exactly how I wanted it lol nothing is EVER simple with my car
Title: Boost gauge calibration?
Post by: MaLicE on March 20, 2010, 07:31:20 PM
looks shagged to me, seen a few omori gauges go that way :( tbh even if you could calibrate it, there must be a reason its out that far...

go careful if you try taking it apart i would just send it back and get a refund, there is always omori gauges on driftworks or ebay... ones that arent shagged.
Title: Boost gauge calibration?
Post by: SiH on March 20, 2010, 09:36:38 PM
As a general rule, if it\'s not zero\'d, it\'s boned. There\'s very rarely an option to calibrate them, even the Expensive HKS DB, Defi etc don\'t have that option :(
Title: Boost gauge calibration?
Post by: m1tch on March 20, 2010, 09:56:24 PM
*sigh* lol its got some Greddy vac hose lol and I think its got a Greddy gauge mount/pod, just need something that works that goes in the middle hehe *sigh* I have matching white face gauges going in for oil temp/pressure and voltage, so this was the matching one I was missing :(
Title: Boost gauge calibration?
Post by: m1tch on March 21, 2010, 01:07:56 PM
Right, because there isn\'t a screw or anything on the back of the gauge I have now taken the gauge apart and have \'reset\' the needle to 0 manually :) I have now fixed the gauge and it works fine :D just been out shopping so I took the rx, mechanical boost gauge now matches exactly with the AVC-R :) the actual mechanical parts behind the gauge look fantastic, really good craftsmanship, it looks like a top end watch :D
Title: Boost gauge calibration?
Post by: AtomicRex on March 21, 2010, 01:27:36 PM
So a good bargin then....despite having to rebuild!
 
Sorry it wasnt quite right....but at least it worked in the end!!
Title: Boost gauge calibration?
Post by: m1tch on March 21, 2010, 01:31:13 PM
Quote from: AtomicRex;680737So a good bargin then....despite having to rebuild!
 
Sorry it wasnt quite right....but at least it worked in the end!!

Its ok mate, thanks for getting it to me promptly :) like you said, it was working when it came out the car but had been sitting around for a while lol also means that I know how they work, so if I need to sort it another time I know what I need to do :D
Title: Boost gauge calibration?
Post by: L18M on March 21, 2010, 01:51:15 PM
good stuff, how did you pull it apart?
i think my vac and boost gauge can do with a twiddle lol
Title: Boost gauge calibration?
Post by: m1tch on March 21, 2010, 03:21:07 PM
Quote from: L18M;680742good stuff, how did you pull it apart?
i think my vac and boost gauge can do with a twiddle lol

On mine there was a gauge rim that was folded over a lip on the gauge body, had to pry that flat and then remove the locking ring, the glass was held in with a rubber sleeve kinda thing that was held in by the locking ring so that could be pulled out, the actual mechanism was held in with the larger nut on the back that went around the barb fitting, after undoing that the mechanism could be removed :)
Title: Boost gauge calibration?
Post by: Prof on March 21, 2010, 03:35:38 PM
Nice work Mr Mitch :)
Title: Boost gauge calibration?
Post by: m1tch on March 21, 2010, 04:44:10 PM
Quote from: Prof;680756Nice work Mr Mitch :)

Well there were 2 options for the gauge:

1. Replace the gauge with a working one and junk the current gauge
2. Try and repair it

So it was actually my last resort on the gauge, if I couldn\'t fix it then it would just be something nice on my desk at work lol
Title: Boost gauge calibration?
Post by: SiH on March 22, 2010, 08:21:05 AM
If I were you I\'d be at the very least checking the calibration against a known good one. It\'s all very well having a boost gauge, but if it reads nothing like the actual value, it\'s sort of pointless.
Title: Boost gauge calibration?
Post by: Prof on March 22, 2010, 12:36:54 PM
Well, his previous boost gauge checked out with the AVC, so if the new guage does as well - it\'s fair to say it must be close enough.
 
In reality you can\'t spend too much time looking at the boost gauge when driving on boost - things tend to happen a little quickly in front of you ;)