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nickleman60
06-29-2006, 11:30 AM
when the motor on my 89sc is off the boost gauge isn't set at 0,its reading about 3" of vacuum.how do you adjust it to zero or is it possible?

David Neibert
06-29-2006, 11:50 AM
Swap the gauge. Just did it last week on my 91 because the gauge quit working. It's a pain because the entire cluster has to be removed because the boost gauge has a screw on the backside of the cluster holding it in. BTW, the fuel level and boost gauge are combined into one unit.

David

XR7inWI
06-29-2006, 03:50 PM
I've got a very similar situation with mine. When the engine is not running the guage sits at about 1" of vacuum. I have seen dash pictures of a LOT of SC/XR7's that are the same way.

So this may be a dumb question but... is it safe to assume that since the needle on the guage is below zero when engine is not running that when at full boost I can add about 1 PSI to the actual reading? I do plan to get an aftermarket guage in the future, but just wondering untill then.

DutchSCFan76
06-29-2006, 03:52 PM
don't replace it, if the needle still moves. Just open the cluster (while its still mounted in the car), remove the needle with a fork, and set it correctly to zero. On a 89-93 its real easy to get to the cluster. Done it already couple of times.

nickleman60
06-29-2006, 04:00 PM
i'll try that fork thing ,what do i got to lose.if it doesn't work or i break the needle i'll look for a replacement gauge,thanks everyone.

DutchSCFan76
06-29-2006, 04:24 PM
there not that fragile. In fact, the inner part of each gauge is much more fragile then the needles itself. When i worked on my cluster (swap to white face plates), all my needles had to come off. My boost gauge / needle was also a bit off. Like + 0,5 PSI instead of 0. Ofcourse this was the time to correct the needle alignment.

Beware that if you once removed a needle, they will never be that tight to the gauge as it was before you removed it.

Good luck.

XR7inWI
06-29-2006, 04:33 PM
Beware that if you once removed a needle, they will never be that tight to the gauge as it was before you removed it.

Good luck.
Maybe add a drop of super glue when puting it back on... ;)

DutchSCFan76
06-29-2006, 05:23 PM
heheheh :D

might do that for my speedo needle. Last time i removed my cluster, and removed the needles i got the speedo needle not right on the gauge. After a few miles driving, my needle fell off :D Now i can open it once more.

But i am going with yet again with a different face setup. Glowing reverse thing, so till i get these, i don't touch my cluster anymore :p guessing how fast you go is fun, lucky I have GPS system wich tell your speed (more accurate too):cool:

DrFishbone
06-30-2006, 12:50 PM
I messed around with bending that copper spring-like thing on the back of mine. I got it pretty close to being set at "0", but then went to far and now it sets at 10psi......at that point, I swapped gauges. :)
I would think that by messing with it at all (moving the needle, bending the spring) would cause it to be inaccurate. I know I can't stand the needle not sitting on zero though....

XR7inWI
06-30-2006, 02:46 PM
I messed around with bending that copper spring-like thing on the back of mine. I got it pretty close to being set at "0", but then went to far and now it sets at 10psi......at that point, I swapped gauges. :)
I would think that by messing with it at all (moving the needle, bending the spring) would cause it to be inaccurate. I know I can't stand the needle not sitting on zero though....
Well, that's what I was wondering..... Is it inaccurate NOW when it reads 10 PSI or would it be inaccurate AFTER moving the needle when it reads 10 PSI?

DrFishbone
06-30-2006, 07:32 PM
I would think, with my limited knowledge of mechanics, that if that thing on the back is a spring, or acts like a spring, that it WOULD cause it to be inaccurate if you moved the needle. My guess would be that messing with the spring itself would probably hurt the accuracy also. If I had my aftermarket boost gauge installed, I guess I would know. :rolleyes:

7birdslater
06-30-2006, 09:24 PM
Its not a spring, but a bellows. It curls or extends with vac and pressure (boost) . Its very mechanical and not all too precise in the first place. I would zero adjust it so it looks right and go with it.

DutchSCFan76
07-01-2006, 02:11 PM
almost all the gauges used stock are NOT reliable or that much 'accurate'. You use it to notice difference at your own setup. But readings i guess are not interchangable with others for comparising.

after i installed white gauges faces (2 times opend my cluser & removed needles), the water temp is off, the speedo needle felt off while driving :D and my rev meter is off + 500 / - 200 RPM.

So its a big pain in the @SS