Re: RE : Success in recharging Audi Bomb

[pjrose@servtech.com (Phil & Judy Rose)]

>Date: Thu, 5 Feb 1998 23:48:56 -0500 (EST)
>From: Dan Simoes <dans@ans.net>
>Subject: Re: RE : Success in recharging Audi Bomb
>
>A warning...
>I mentioned this repair to my mechanic, and he suspects
>that in most cases, a pinhole in the bladder will allow
>the pressure to leak out again over time.

This is probably pure speculation on your mechanic's part--unless he's done
some recharging himself and found that it doesn't hold. Any rubber septum
(absolutely free of defects) will have some measurable permeability to many
(most?) gases--certainly nitrogen included. Hence there will _always_ be a
natural, unavoidable rate of gas "leakage". It's quite possible that most
bomb failure is simply caused by this permeability, in which case the
recharge approach ought to work OK.

>He also suspects that the nitrogen leaking out and seeping
>into the pentosin is/was a cause for some of the leaks
>he's seen.

The cause of pentosin leaks? Could be, if the gas isn't soluble in pentosin
and tends to collect adjacent to the rubber seals (reducing lubrication?)


>It's worth the experiment, but let's see how Joel's bomb
>holds up before you all start drilling :)

Amen. I hope someone'll do a bench test with a gauge attached for a month
or two.

Phil Rose