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[TugCowboy]

Hi Guys,

I've got a 38" fibreglass leisure boat hull which I fancy turning into something a bit more rough and ready like this:


I'm looking to put one or possibly two jet drive units in it (it'll be quite heavy when done so two might be required) but not really sure what's available out there.

I can only find either the £220+ units, which are way out of my price range for this build as I have another "expensive" one on the go. Or the cheap mini units which I don't see being powerful enough.

What are my best options?

Any and all ideas considered!

Alex

[Time Bandit]

I think this should be a job for 2 28mm Kehrer units:
https://www.kehrer-modellbau.de/en/kmb-jet28/jet-drives/



If you need it faster (but I think the boat is too small) this would be your choice:
marinetic 35 mm jet : http://www.marinetic.de/index.php?cat=1733

[TugCowboy]

Those Kehrer units look very nicely suited, will measure up later.

£101 for 2 including the single servo reverser linkage is not too bad either (as long as the wife doesn't find out!)

Alex

[Klunk]

That will cost you more cake!

[Time Bandit]

The "Kehrer" Jet drive“s are the standard jet drives here in germany.
Very good quality (compared to the Graupner ones) and pretty steady.

I“d just buy some spare parts with them, they tend to suck up small stones if you run them in shallow water and without safety guards and these will destroy the impeller and stator parts.

[TugCowboy]

Klunk, I think I've used my annual cake creation allowance from Mother In Law now until the Christmas cake arrives in December!

Time Bandit,

Can I ask what you use for a safety guard? I was thinking about this quite a lot as my local pond is not shallow but can sometimes have a bit of weed/twigs floating.

My plan was to use cut down filters from Aeration Heads on taps. They have a very fine series of mesh inside them which stops anything but the very smallest particles coming through and won't affect the water flow.
Something like this:

[TomHugill]

Tug, some mesh should do, you don't want to inhibit the flow of water in. To be honest some bars spaced at 10mm across the jet should stop most weed that would cause you issues.

[Time Bandit]

I just use 0.3 mm "spring steel" wires at a distance of around 5 mm.
You should not put anything on the intake in 90° to the driving direction, it makes the jet cavitate much earlier.

Sucking up green parts is always a problem but you cant avoid it perfectly without ridiculously disabling the jet drive.