[PSUBS-MAILIST] oil compensation

James Frankland via Personal_Submersibles personal_submersibles at psubs.org
Tue Jul 22 05:41:01 EDT 2014


Hi Carsten,
Jim I think forwarded a message you sent in 2010 which had a picture.  Its
obviously an old link but do you have another copy you could send?
Many thanks
James


http://www.euronaut.org/content/upload/notes/IMG_3321a.jpg


On 22 July 2014 09:51, Alan James via Personal_Submersibles <
personal_submersibles at psubs.org> wrote:

> But wait there's more....below is a summary by Jim of advice for oil
> compensating & Carsten's cynical
> additional points.
> Alan
>
>    - *o*: <personal_submersibles at psubs.org>
>    - *Subject*: Re: [PSUBS-MAILIST] illustration is this what you mean
>    sort of?? pressuriz...
>    - *From*: MerlinSub at t-online.de
>    - *Date*: 05 Dec 2010 09:43 GMT
>    - *Reply-to*: personal_submersibles at psubs.org
>    - *Sender*: owner-personal_submersibles at psubs.org
>
> ------------------------------
>
>  9. Run the motor a half hour with the boat in the water and see may how the hot oil gets out of the weakest point by internal overpressure..
> 10. Switch of the motor and let the boat still in the water for two hours or so.
>     Open the engine the next weekend in you shop and found partly water in it because of the underpressure creates as the oil cool down..
>
> The best for the seal is if it see no pressure differtial doesnt matter from which side. So logical the bladder has the same high as the motor.
> A deeper installed bladder indicates a leak by oil getting out in the water, A higher install may not.
> A higher installed bladder indicates maybe allready a leak onshore - and thats maybe the better solution.
>
> The best solution is that the hose work between using device and bladder is from clear material and has a loop higher than the user and the bladder. So air in the system can be easy spotted.
>
> See here: http://www.euronaut.org/content/upload/notes/IMG_3321a.jpg
>
> Euronaut has seven bladders on:
> - Stern Thruster (oil)
> - Bow Thruster (oil)
> - Anchor winch motor (oil)
> - Propeller shaft (oil)
> - Void space frame cave between fwd.ballast tank and pressure hull (coolant water)
> - Void space frame cave between aft.ballast tank and pressure hull (coolant water)
> - One bag for all three fix rudder skegs (coolant water)
> - Side Rudder and Stern deeprudder are also filled with c.water but without bags.
>
> See also the other mail I just send.
>
> vbr Carsten
> ------------------------------------------------------------------------------
> "This mail is shareware - for any tipp you find usefull please send a dollar."
> ------------------------------------------------------------------------------
>
> <JimToddPsub at aol.com> schrieb:
> > All,
> >
> > I'm having difficulty understanding the need for the bladder,  and it seems
> > like an additional complication and an additional point of  vulnerability
> > along with the line.  How would this work:
> >
> > 1. Install a bleed valve at the uppermost point of  the motor housing.
> > 2. Install a fill valve at the bottom of the motor  housing.
> > 3. Attach a fill line (equipped with a pressure gauge) to  the fill valve.
> > Purge all air from the fill line prior to attaching it to the  valve.
> > 4.  With the bleed valve open, fill the motor from the  bottom until oil
> > discharges from the bleed valve.
> > 5.  Turn the motor shaft by hand and vibrate the motor to  release any
> > trapped air bubbles.  Close the bleed valve and allow the motor  to sit for a
> > couple of days undisturbed.
> > 6.  Open the bleed valve and add more oil to drive any  residual bubbles
> > out.  Close the bleed valve while pressure is still being  applied to the fill.
> > 7. Adjust the pressure from the oil pump to the desired  pressure, then
> > close the fill valve.
> > 8.  Release the pressure on the oil pump/fill line, then  disconnect the
> > fill line.
> >
> > This seems logical to me, but I'd like to hear from the voice  of
> > experience.  Does 14 lb. seem like a reasonable differential pressure  for set up?  I
> > expect to start with new Minnkota motors, and I haven't  addressed sticking
> > with the factory seals vs retrofit seals.  My intended  operational depth
> > is 300 feet.
> >
> > As always, comments  and criticisms are eagerly  invited.
> >
> > Thanks,
> > Jim
>
>
>   ------------------------------
>  *From:* Alan James via Personal_Submersibles <
> personal_submersibles at psubs.org>
> *To:* psubs.org <personal_submersibles at psubs.org>
> *Sent:* Tuesday, July 22, 2014 8:28 PM
> *Subject:* [PSUBS-MAILIST] oil compensation
>
> I found some comments that Carsten made about oil expansion & compensation.
> Someone was interested in hearing them if I found them. The thread was 5
> Dec 2010.
> Alan
>
> Alan and the other gentlemens,
>
> our expierence with oil filled motors, batterys or even propeller shafts is that the oil expand if the motor is runing longer time.
> Simple because its warm up. We had that problem on Eurosub on the first dives.
> And on Euronaut we filled the bladder complet up and the get pretty hard in the hot summer just by sun heating the sub.
> A full filled bladder with over pressure creates a lot of interal
> pressure in the wrong direct - a lot of force for the bladder itself and hose work.
>
> Therefore our bladder are only half expand during the filling. But still free of any air.
> An other point is that the bladder has to be not to small.
>
> To create a slightly overpressure on the motorseal you just install the bladder below the motorcasing.
> But we found out that on trolling motor (electric outboards) this is not nessesary. There seals are good for some
> douzend feets at least - so you can install the bladder else were.
> Filling is simpler if the bladder is slightly over the motor - you can vent the system direct on the filling point.
>
> Another point is that we install now one bladder per motor  - in the earlier sub (Sgt.Peppers) we install a central
> one for all motors. Hard to find a leak after a dive with all the T-crossing piepings and motorseals..
>
> vbr Carsten
>
>
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20140722/832870f0/attachment.html>


More information about the Personal_Submersibles mailing list