Re: [PSUBS-MAILIST] Seals again

["Ty Alley" <tydes@shreve.net>]

Farallon states that their DPV is tested to 400ft.(www.farallonusa.com) and
the Gavin scooter will do 300ft.(www.halcyon.net).  Does anyone have access
to either of these for closer inspection of seals, housing thickness etc?
It appears to me that these are all just sub thrusters with handles.
Food for thought
Ty
----- Original Message -----
From: Steve Lindblom <s_lindblom@conknet.com>
To: <personal_submersibles@psubs.org>
Sent: Monday, October 02, 2000 9:46 AM
Subject: [PSUBS-MAILIST] Seals again


> I just ran into a friend who has a Dacor DPV scooter, and he'd just
> replaced the seals, and still had the old one, which he gave me. I was
> suprised to see that it was just a plain old rubber lip seal, the kind
with
> a little spring inside to hold tension on the shaft, as used for the rear
> oil seal on a car engine. He got replacements at the local bearing supply
> shop for a couple dollars each (it uses two in series).
>
> Dacor says the scooter is good down to 160', and I think the unofficial
> word is that they are good down over 200'.
>
> What I found surprising is that these are just about the simplest seals
> imaginable, and I'd always assumed they wouldn't be up to this application
> given the fact that they are running in water not oil, and are exposed to
a
> fair amount of pressure. But there are a heck of a lot of Dacor and Apollo
> scooters out there, and seal problems don't seem to be common.
>
> The other neat thing is it is almost a direct fit into the little 30lb
Minn
> Kota flea market motor I've been using as a test bed - there's even room
> for two of them, above the standard seals. I say almost because the hole
> around the prop shaft on mine is a little corroded, and I don't know what
> it originally measured. I may have to clean it up a bit and sleeve it, or
> maybe just some Loctite Sleeve Loc will do the job. Probably worth
> mentioning that the seals should be installed "backward" in this
> application, that is to say, with the open/spring side facing out so the
> pressure tightens the seal.
>
> So we got the Dacor using $3 seals for 200', and the Scubapro "Salad
> Shooter" with a Minn Kota motor (the entire module, skeg and all, slung
> down below the battery housing and disguised with a plastic shroud)
merrily
> cruising at 180'. Gentlemen, is pressure compensation really necessary?
>
>