can I do this ???

[tboss]

I want to install a water water pressure switch on my 1986 C/C scopion 266 and need to know if this is possible on a 350 carbed engine . I want to be able to monitor the cooling water pressure in my raw water system with an alarm since this unit didnt come with one. If I can do this where can I find one. tks Terry

 

[Bondo]

Re: can I do this ???

If I can do this where can I find one.

Ayuh,.... Donno....

You can do anything you want,... If you can find the pieces....
I know you won't find this in "Kit" form...

 

[Howard Sterndrive]

Re: can I do this ???

^^^ omc outboard w.p. gauge kit used to come with about 15' of plastic hose. You could adapt the pickup to a prestone flush kit in the supply hose.

 

[Robj]

Re: can I do this ???

You can probably get a pressure switch and plumb it in. There is not a whole lot of pressure on the raw water side, but I imagine it could be done. Really what you are looking for is flow, maybe a flow switch of some type would be better.

Have a great day,


Rob.

 

[bomar76]

Since we are not running a circ pump on our 385 stroker, but a crossover I wanted to closely monitor water pressure (have an Alpha GenII drive, using the drive pump only)
Bought a water pressure gauge from SS Competition http://www.sscompetition.com/product_description.php?MenuId=1&product_id=183
Installed in dash
Ran tubing back to engine
Tapped water port on rear on intake.
Ran braided stainless stell line from engine to tubing (Summit Racing)
http://store.summitracing.com/partd...1&part=ATM-3227&N=700+-43859+115&autoview=sku
zip tied it all up and good to go.
As for the alarm, would be easy to find a switch with the appropriate values to plumb in and add a Radio Shack alarm.
No really good pics of the engine side, but here is one:

 

[bomar76]

Re: can I do this ???

 

[Bondo]

Re: can I do this ???

Since we are not running a circ pump on our 385 stroker, but a crossover I wanted to closely monitor water pressure (have an Alpha GenII drive, using the drive pump only)

Ayuh,.... So what are you seeing,..?? What's Normal, at what rpms,..??

 

[dan t.]

Re: can I do this ???

there is a cooling water flow detector made by Aqualarm, several pipe sizes available , bell or light indicator p/n aal rbws-12

 

[bomar76]

Re: can I do this ???

Ayuh,.... So what are you seeing,..?? What's Normal, at what rpms,..??

Depending on RPM and trim I see 5-10 psi idle, 12-16 psi running up to 3500 rpm, and WOT (5200 on our stroker) it will run in the lower to mid 20's.

All numbers are with the thermostat open.

When the stat is closed the pressures shoot up 10-15 psi over the above numbers. I't's funny watching the gauge fly around when the stat cycles

 

[Bondo]

Re: can I do this ???

Ayuh,...

Thanks for the Great Info,....

I picked up a gauge for my boat, but haven't gotten around to installing it yet....
And,...
I've been curious about What the expected pressures might be....

 

[bomar76]

Re: can I do this ???

Ayuh,...

Thanks for the Great Info,....

I picked up a gauge for my boat, but haven't gotten around to installing it yet....
And,...
I've been curious about What the expected pressures might be....

Pressures were a lot higher than I ever expected from that little GenII impeller.
When we decided to eliminate a circ pump I was sure we would have to go to a crank mounted raw water pump for cooling the engine and riser. Would have still kept the outdrive impeller for cooling the drive and the power steering cooler and then just dumped the water overboard though a thru hull.

 

[JustJason]

Re: can I do this ???

alot of times I wonder if you even need circulating pumps. Even pre alpha impellors, when they are working properly, throw alot of water.

 

[Bondo]

Re: can I do this ???

Ayuh,.....

On my present barge with the Alpha 1 drive, I fought a slight occasional Overheat issue for Years...
Til I figured out you Need the check-balls in the T-stat housing with the early Alphas....
I guess the check-balls went away with the change to the Gen.II Alphas....

The barge that I'm puttering with now,....
Was going to get Either the Gen.I, or the Gen.II, as I have both transom assemblies laying around...
But,...
I pulled a Cool Deal last summer,+ picked up a Complete Bravo I early edition(outdrive,+ transom assembly),+ a complete Alpha 1 gen.I outdrive for a mere $1300.....
Now I have another Spare Alpha 1 drive for the present barge,....
And,...
The Old Town Atlantis project will be getting the Bravo I hung on it,+ the bored & stroked 327 in it....
Bottom line is,... I now have alittle more breathing room to play with the 383 build....
And it'll be fed by a block mounted raw waterpump,+ a thru-hull fitting...
(and probably freshwater cooled,.. only because I have a system laying around,.. probably need Another pressure gauge then, huh,?? )

I wouldn't have Thought that either the earlier Alphas, or the Gen.IIs would support running Just a Cross-over tube.....
I know the Cross-over tubes are popular with the serious Jetboaters,...
But,..
With a V8 spinning a Real Jetpump,....
It's a question of Limiting the water, not how Much there is....

 

[bomar76]

Re: can I do this ???

Our backup plan (if the need arose) for a raw water pump was a crank mounted pump, specifically the Johnson F6 (10-24232-1). It mounts via a simple bracket, and is easily accessable for impeller changes.

There were a lot of naysayers on other forums I frequent that swore up and down we would have overheat problems without the circ pump. The Alpha GenII pumps a lot more volume than I ever expected.

The thermostat housing we are using only has a 8AN bypass and only has 2 lines for the exhaust manifolds, you plumb those to the bottom of manifold and plug the riser fittings. Thois also caused me some concern. The risers do run hotter, but not too much so (after all we are making a lot more HP, and that comes from burning more gas, so of course we are producing more heat).
I keep meaning to shoot them with an IR guns but never have done so.

We have never experienced any problem with engine temp, just the slightly elevated riser temps.