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[hoverboy]

Hi Chaps,

I am trying to fit a water cooling system to my Perkasa. There is no problem with the coil or the outlet. However because this is on an existing build I cannot fit the pick up behind the propeller as there is just not  enough room.

Would it still work if I fitted it slightly in front of the propeller and to the left or right?

Pete.

[FullLeatherJacket]

Pete
Very, very doubtful, mate. If space really is that tight, try some lateral thinking. Could you perhaps modify the rudders so that they have hollow shafts which could be used as water pick-ups?
Just a thought..........suit yourself.
FLJ

[J.beazley]

I didnt think it matters too much on where the pick up is as the momentum of the boat going forward pushes the water up the inlet pick up anyway.

I know on my fast electrics i have the props out the back of the stern with the water pick up glued under the hull just like a naca duct does the job for me.

Jay

[DickyD]

Hi Pete
Just fitted one to my MTB this afternoon. It is an ali tube set at 30 degrees and is to one side and more or less level with the prop. According to the instructions this will work well

[hoverboy]

Thanks for the info chaps.

looks as if I can go ahead and fit it as far back as possible. If Dicky D can do it and it works then I am in with a chance. Anything is better than the set up I have at the moment where the motor gets hot.

Pete

[John W E]

Pete, hi there

There is a bloke on here who built HMS Leeds Castle at 1:48 Scale, and the water pick-ups are situated in the 'A' frames directly in front of the propellers (the 'A' frames are aerofoyle shaped hollowed sections with slots cut in them).  

This works quite successfully as water pick-ups.    He did manufacture trial rudders with water scoop pick-ups either side of the rudder blade, the passage of water was through the hollow rudder tube.  The problem was that the water connection at the top of the rudder post began to leak after several movements of the rudder.

No doubt, if you can think of a way of overcoming this, (as the person had used silicon tubing, secured by home-made brass jubilee clips which leaked - and I know the person got fed up trying to correct this) he then tried the 'A' frame method, which does work very well.

aye
john e
bluebird

[Stavros]

Pete I had a similar problem with a MFA 850 in a Sea Queen I installed a washer pump to pump the water around the coil and I still get over 2 hrs sailing out of her


Stavros

[BobF]

Hi,

Try and use as large a bore pipe work as possible for the supply. I had a cooling problem with a fast electric, and solved it by using aluminium pipe with a larger bore than available silicone tubing for the straight runs. Even if the cooling coil is thinner.

Bob

[red181]

Due to the shape of the hull on my Huntsman, I could not put a water pickup inline with the rudder and prop, I put it slightly to one side. It didnt work, I even tried turning it towards the prop, and fitting a wider pick up neck, it only worked at high speeds. I got an old screenwash motor from  a scrapyard, wired it to the motor connections, it was then proportional to the throttle, with a switch to turn it off when it was not required, not ideal, but it worked!