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Re: Guzzler 400 return
By:Pete Roszyk
Date: 4/28/2001, 11:38 am
In Response To: Guzzler 400 (Bill Sivori)

Hi there.

The stock Guzzler spring, capable of an 11- or 12' lift on the suction side, is much stronger than we need, which is maybe 6" of lift. At 22 or 24 times the strength we need, then, and because we need to work the spring with every stroke, about 95% of the effort exerted is wasted energy. Only that last 5% of effort goes into actually pumping the water out of the boat.

My first Guzzler-in-a-Coho was a springless hand-operated model which I adapted with a footplate and a bungee for the return, or suction, stroke. The footplate was on the tall side so as to provide an attachment for the bungee as well as get it up into the peak of the deck and out of the way.

Run the bungee back along the inside of the peak to a fairlead jam cleat epoxied to the underside of the deck near the cockpit rim. The fairlead keeps the bungee from dropping down into the bottom of the cockpit, and if you put a knot in the bungee on the cockpit side of the cleat, it won't even sag into the footwell.

I was surprised how little tension on the bungee is needed to operate the pump for its return, i.e., suction stroke.

On my second and third installations I used the button models with the spring, and now I wish I hadn't. My leg gets tired, and the button hits me too low in the weaker middle part of my foot rather than the strong part at the ball of the foot. As a result, I have to switch feet every minute or so.

I'm considering adapting my button pumps with a foot pedal. A foot plate can be attached to a hinge mounted (epoxied) in the keel of the cockpit, and then perhaps a convex-curved spline on the button side of the pedal to slide along the button as it is stroked. If you remove the spring, you'll have to rig up some kind of linkage connecting the button to the pedal.

In my current installation, I'm going back to adapting a hand-lever model pump to have a foot pedal and bungee system. For the one after this, I have one of those accordian-type plunger pumps; I want to see if it can be easily adapted to our needs. If so, for $8 or so, that would be ideal, but there will be more work required to get the valving and piping right.

Erez speculates that weaker return springs would increase the pumping chamber fill time. If that is true, it is a very, very small increase, and not a practical problem for us. I might agree if the inlet piping diameter was very narrow, creating a flow vs. time restriction, but in the Guzzlers I don't think it's a concern. Our requirements are really very modest as far as pumps go.

There's some related discussion and installation photos at my website.

in Snohomish, WA

Messages In This Thread

Guzzler 400
Bill Sivori -- 4/27/2001, 10:34 am
Re: Guzzler 400 return
Pete Roszyk -- 4/28/2001, 11:38 am
4 return ideas
mike allen ---> -- 4/27/2001, 12:01 pm
stainless springs
Sam McFadden -- 4/28/2001, 11:00 am
Re: stainless springs
mike allen -- 7/16/2001, 8:02 pm
Re: stainless springs
Sam McFadden -- 7/16/2001, 11:49 pm
and thank you, too.
mike allen -- 7/17/2001, 9:00 pm
Re: stainless springs
Dale Frolander -- 7/17/2001, 2:26 pm
Sam McFadden -- 7/17/2001, 3:25 pm
Re: 4 return ideas
Erez -- 4/27/2001, 4:54 pm
Re: 4 return ideas
mike allen ---> -- 4/27/2001, 8:31 pm
Re: Suction Head
Shawn Baker -- 4/27/2001, 5:04 pm
Re: Suction Head
Val Wann -- 4/27/2001, 5:35 pm
no suck, no head
mike allen ---> -- 4/27/2001, 6:43 pm
Re: no suck, no head - it CAN be done !
Erez -- 4/28/2001, 11:18 am
400 v. 500
Pete Roszyk -- 4/28/2001, 11:54 am