DIY kayak pump setup

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MrV
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DIY kayak pump setup

Post by MrV »

Morning all, I am trying to put together a kit to basically pump up our 2 kayaks electronically without using the car however I know nothing about anything! I have ordered a dual stage SUP pump and I've ordered a croc clip to 12v socket adapter which will connect to a small 12v 5h quad bike battery I have, does anyone know if this small battery will do the job? if not I have an 8000mah USB power bank, would that be better?

Thanks, Ben
Rorschach
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DIY kayak pump setup

Post by Rorschach »

You need to know how many amps the pump draws and approx how long it will take to inflate the kayaks, then you can work out the size battery you will need.
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DIY kayak pump setup

Post by kellys_eye »

If you need to pump more than 30 seconds then you're as good as sunk! Some sump pumps can shift 1,000's litres per minute but even a small one

https://www.asap-supplies.com/products/ ... gKw-vD_BwE

does 23 litres/minute so 2 minutes is equivalent to 50kg of water..... I think you'd notice that!

Anyway, pump shown draws 2A so a 5Ahr battery would (in theory) run it for 2.5 hours........ don't even think of a USB pack as they are only 5V anyway.

You can fit the pump/battery and float switch if you want an automatic system that empties you whilst rowing (kayaking).

Positive of battery to float switch (if used) then other side of float switch (any way round, the float switch is not polarity conscious) to positive of motor. Negative of battery to negative of motor. Job done.

Replace the float switch with a simple PUSH button (if you fit a toggle switch you'd likely leave it on and the pumps don't like being run dry) for a manually operated version.

For peace of mind also fit an inline fuse (auto shop accessory) rated at 5A and use the correct wire (18 gauge or 1.5mm should do).
Don't take it personally......
Rorschach
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DIY kayak pump setup

Post by Rorschach »

I think he means an air pump for inflatable kayaks.

USB power banks can be used for 12v if they are the USB-C Power Delivery type, whether it could output sufficient amps to blow up a kayak is another matter though.

I run my little 12v air pumps (one for air beds and one for tyres) from a spare car battery, works well, but heavy of course. If I am near the car I just run the engine and use the socket in the car.
MrV
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DIY kayak pump setup

Post by MrV »

Rorschach wrote: Wed Apr 07, 2021 1:06 pm I think he means an air pump for inflatable kayaks.

USB power banks can be used for 12v if they are the USB-C Power Delivery type, whether it could output sufficient amps to blow up a kayak is another matter though.

I run my little 12v air pumps (one for air beds and one for tyres) from a spare car battery, works well, but heavy of course. If I am near the car I just run the engine and use the socket in the car.
Yep I mean an air pump for kayaks, this is all I can find on the one I have ordered, it says max loading is 15amp:

20 PSI SUP Pump - use from 12 volt via a cigarette socket. As long as your SUP requires 20 PSI or less, this will do the job. Complete with adaptors.
Key Features
A Very high pressure 12V SUP pump
Automatic switching from first to second stage
Pressure: 20 PSI / 1.38Bar
Inflate and deflate
Powerful 12V compressor
Switches off automatically once pre-selected pressure is reached
Pressure unit selection
Robust, high quality hose and socket and adaptors
Max loading is 15Amp
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DIY kayak pump setup

Post by mudmouse »

15A is quite a load - I thought most car cigar lighter types are designed for 10A max but I may be wrong.
A small 12 V dedicated battery should laugh at the load though assuming the following.

You only need to pump for 10 minutes
You draw a 15A average (although it will probably average out at much less than this during a single inflation).

This would use up a maximum of 2.5AHrs from the battery.
Ideally, you do not want to take more than 30% of the battery capacity at a time - to have a good battery life.
This means you would need an 8.3 AHr battery so for good measure a 10Ahr unit would be more than adequate - say -

https://www.amazon.co.uk/BATTERY-DEEP-C ... 605&sr=8-3
MrV
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DIY kayak pump setup

Post by MrV »

mudmouse wrote: Wed Apr 07, 2021 2:45 pm 15A is quite a load - I thought most car cigar lighter types are designed for 10A max but I may be wrong.
A small 12 V dedicated battery should laugh at the load though assuming the following.

You only need to pump for 10 minutes
You draw a 15A average (although it will probably average out at much less than this during a single inflation).

This would use up a maximum of 2.5AHrs from the battery.
Ideally, you do not want to take more than 30% of the battery capacity at a time - to have a good battery life.
This means you would need an 8.3 AHr battery so for good measure a 10Ahr unit would be more than adequate - say -

<a href="https://www.amazon.co.uk/BATTERY-DEEP-C ... 605&sr=8-3" class="skimlinks-unlinked" data-skimwords-word="https%3A%2F%2Fwww.amazon.co.uk%2FBATTERY-DEEP-CYCLE-REC10-12-YUASA%2Fdp%2FB0118KDTYE%2Fref%3Dsr_1_3%3Fdchild%3D1%26keywords%3D12v%2B10ah%2Bbattery%26qid%3D1617806605%26sr%3D8-3" data-skim-creative="500005" title="" style="">https://www.amazon.co.uk/BATTERY-DEEP-C ... &sr=8-3</a>
From what I see on youtube the pump ordered will inflate a much larger paddle board with a much higher PSI in around 10 mins, thanks mudmouse I shall get a higher rated battery many
Rorschach
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DIY kayak pump setup

Post by Rorschach »

Yes a separate battery would be best for this application. A small leisure battery would be better than a car battery, with care it will last a lot longer but will be more expensive. A cheap car battery will do the trick but require more maintenance and won't last as long, depends what you want really.

I keep my old car batteries for jobs like this, they last a few years doing low power jobs like tools and 12v lights and are essentially free to me.
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DIY kayak pump setup

Post by dewaltdisney »

I have a jump pack for the car if ever needed, and it runs a tyre compressor. One like this https://www.toolden.co.uk/p/sealey-rs13 ... peak-amps/ Any use?

DWD
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kellys_eye
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DIY kayak pump setup

Post by kellys_eye »

MrV wrote: Wed Apr 07, 2021 2:17 pm Yep I mean an air pump for kayaks,
::b d'oh.... :lol: sorry!
Don't take it personally......
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ericmark
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DIY kayak pump setup

Post by ericmark »

Never tried with kayaks, but I know with air beds you need volume not pressure, so a centrifuge pump not reciprocal, so starter pack yes, but not the built in pump.
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