Pressure gauge help

[EIGHTWGT]

I was diving offshore Jax yesterday and had a PG 'failure'. I reached down and flipped over my PG to read it - 3800 PSI - no worries... ( I am at 85' sw)

A few minutes later I look again and when I flipped the guage over - to my surprise the needle went from about 1500- 3500 !! I did it again same result.... I started thinkin I was seeing things ! I did it one more time at about 3200 PSI and it did it again - I called the dive... Was I being too cautious ?
Have you guys ever seen this ? Its a PG I got a Divers Supply - It says ' Made in Italy on the back, and the face of the guage.... When you shake the gauge the needle will "vibrate' a lil back n forth since I had it....
http://www.diverssupplyusa.com/index.asp?PageAction=VIEWPROD&ProdID=16359

I didnt dive the rest of the day due to it... I have it hooked to a tank now - it seems fine- suggestions / comments ??

Thanks

Tom

 

[JimC]

You tank was not turned on all the way, or there was an obstruction in the air path (reg/valve/etc)

Hook it up to a tank and crack the valve, then breath a regulator. You should see similar behaviour. That is the most likely cause of the issue. Next time make sure your tank is on!

If your paranoid, you could have your regs serviced and your tank valve inspected but that is likely not needed.

 

[EIGHTWGT]

Tank was on - I allways double check before I dive. I also breathe both regs, purge them, check pressure, inflator. I did say to my dive buddy that when I purged my regulator (primary) that it sounded 'slow / low pressure' before the dive... I wrote it off as my being over cautious.....

Then the pressure guage thing.

By the way - this is a new Mares MR12 first stage - has about 25 dives on it. It was a combination of the purging incedent, and the pressure guage that stressed me and made me call the dive...

 

[Doc Intrepid]

good call.

I would've called the dive also.

Jim's explanation seems to be the most rational, but if you're sure the tank valve was on completely then perhaps it was something else. (While rare, weird things have happened. It isn't unknown to have tiny rust particles from inside rental tanks blown into regs resulting in all sorts of frustrating consequences...DAN had some photos of these types of situations in an article last year. Dunno if you were using rental tanks...)

So long as your SPG is working well on another tank, give it a shot. I wouldn't replace it just yet either, but I'd do some 'less rigorous dives' with it a bit before doing any major drops.

Best,

Doc

 

[EIGHTWGT]

good call.
Doc

thanks Doc...

Upon further inspection..... When you breath through the regs... the needle is moving on the PG - indicating some sort of 1st stage problem. I am bringing it in on Monday to have to looked at. If I am correct - the pressure shouldnt drop because I am breathing on the regulator - especially enough to show an obvious drop on the PG - although nothing like it did yesterday - an obvious problem.....

I am glad I called my dive... nothing worth a 1st stage failure at 85 fsw !!

 

[spectrum]

If I am correct - the pressure shouldnt drop because I am breathing on the regulator - especially enough to show an obvious drop on the PG

That's what I was taught.

When you tried to pull enough gas through the system to sustain you at multiple atmospheres's the inabaility of the first stage to supply would be exacerbated, hence the wild needle swings during the dive.

Pete

 

[Ben_ca]

That was a good call...

Your brain is your best dive computer

If there is any doubt start your ascent...

 

[Captain CaveMan]

i would inverst in a new ps guage. when i delt with psi gauges with my old work we only got psi guages that were oiled filled. this way the needle would not jump when shooken since i worked on running engines. pluss the oil keep the guage accurate.

 

[pipedope]

If something doesn't seem right then it is proper to call the dive.

Junk in the inlet filter of the first stage can give this problem.
This is even more likely the cause if the problem continues with the tank valve all the way open and/or on a different tank.

 

[Diver0001]

So long as your SPG is working well on another tank, give it a shot. I wouldn't replace it just yet either, but I'd do some 'less rigorous dives' with it a bit before doing any major drops.

Best,

Doc

I agree with Doc that calling the dive was the correct thing to do. I disagree, however, with giving the gauge the benefit of the doubt. I guess I'm different than he is about this but if you have any doubts about a bit of gear (especially something this essential) then it's best to send it for service. In this case (and I'm assuming that you're 100% sure that your tank was open) I would suggest sending it back to the manufacturer under warranty and getting it tested by experts.

R..