What am I doing wrong now

[Andy CParticipant @andyc56856]

Well, that was a tale of two halves, hits and misses, starts and stops etc etc.

Once upon a cold and snowy Sunday morning at the lakeside… Oh hold on wrong website.

Anyway, it works……sort of. Every thing was back to front and wrong side round. Easily fixed lakeside by flipping the reverse switches on the transmitter. So now going forward when asked and left when prompted. Squirters not working still and then she just stops. Near the edge thank goodness. Waiting for wind to push it to the side so we can retrieve and investigate. Seems the propshaft is too tight. Easy I think to sort out. Cold numb fingers not best for handling little 1.5mm Allen keys but persistence is everything. Sorted and back in the water and off she goes again. Then she throws another wobbly and keeps cutting out.

So what is wrong. Well;

1. The servo leads do not have the little tab on them and following the instructions that came with the viper 15, thought I had them the right way round. Seems not, so will swap them and check again.

2. Prop now turns easily enough, but will whack some light grease down the tube to help ease things a little.

3. Cutting out problems. Absolutely no idea. Did not do it before and runs nicely enough out of the water. Could it be pulling to much power and cutting the ESC out. It is running p80 speed controller rated at 20 amps. So should be okay right. Only using a speed 400 motor. How do you test it?

4. Squirters not working. So I thought it might be a problem with the pump not getting any water as it runs well enough. You can hear it. You knoow when you put a glass directly in water it creates an air gap, thought this might be the problem as the inlet is facing directly downwards. Did an experiment in the sink with a glass and a sieve to see if the sieve breaks the meniscus. Yes it does. So added a little gauze over the inlet to see if that helps. If nothing else it will stop bits and pieces getting in at least. Maybe the pump is at fault. May buy a new one and try again. Also now have the viper 15 hooked up so it can pump both nozzles when engaging forward and reverse, but pump cuts out at full throttle forward. Again maybe pull in too much current for it to cope with?

Any thoughts?

Cheers Andy

[ashley needhamParticipant @ashleyneedham69188]

The weather….. Popped to pond and stood in the snow for 10 min and then stopped off at trevors for a cocoa and show`n`tell.

​Noel. The little tab on the servo/esc lead is to stop them being plugged in the wrong way round BUT a lot of receivers dont have the slots to I cut the tab off…not necessary on a lot of gear. ALL the plugs will be the same way round…..so black or brown all one way.

No…noi grease. Tighten the adjusting nuts so there is NO SLOP…I use a nylon washer (made from plastic milk carton) on one or both ends and tighten so there is JUST a perceptible drag…and no more. This should stop water ingress. Not a universally held view I know.

​Cutting out like that usually receiver position ….2.4 needs to be above waterline and the ariel of a 27M set needs similarly to be raised and not all bunched up. Separating the rcvr and esc is useful. OR of using separate rcvr battery might be low voltage…OR main batt low voltage.

Pump…could be anything!! inlet filter a good idea anyway. Assume pump is self priming if above waterline??

​Ashley

[Andy CParticipant @andyc56856]

I did some testing this afternoon after stripping the electrics out again. It seem the pump does work and does pump, but it has to have some water already in it for it to work. now the problem is, when you take the boat out of the water all the water in the pump drains out. so next time around it will not work. I have the pump intake through a hole in the bottom of the hull and the pump horizontal. I think on cars it is fit vertical with water always sitting in the pump inlet. I now need to come up with a way of trapping water in the pump when the boat is removed from the water.

I wonder if fitting an elbow to the inlet hole will help. The elbow will face forwards and once the boat is driven it might fill the pump fro the water pressure. Hmm, some testing required me thinks. More soon.

Any other suggestions welcome.

Regards

Andy

[ashley needhamParticipant @ashleyneedham69188]

Andy. All the water squirter pumps I ever had in my old cars sat well above the bottle water level (self priming). I wonder if you have a bit of a leak or something?? Does the pump self-prime out of the boat with a pipe in some water?? The other question might be…is it a 12V pump you are trying to run on 7.2V (for instance) so the pump is not working at full power?

​All the other chaps simply have a tube or whatever in the bottom of the hull, an elbow should not be necessary.

Ashley

[Tim CooperParticipant @timcooper90034]

Andy

I have two boats with pumps to provide water for fire monitors. I have a 12v battery to supply in each to power the pump. Neither pump needs to be primed, in fact I run after sailing to empty the pump. Both take the water from underneath the hull.

Tim

[Andy CParticipant @andyc56856]

Okay, so I have done some more testing in the sink. It appears as though the car washer pump I have, twin outlet, requires no air to be in the system. For example, if I run the pump with just the end unconnected to the nozzles they will not squirt water. If I put a kink in one of the hoses and fire it again, it squirts. So I am guessing that when it is in a car, there must be no air in the system, in fact it would probably still have some residual water in the pipes creating an air stop. So, how can this be achieved in the boat? Maybe some sort of one way valves installed in the pipework? Hmm, either that or will a single outlet be better and have a Y piece to split the water flow to 2 monitors. Would you still have the problem of air in the system. I have a big hole in the bottom of the boat now where the pump sits, so cannot easily install one of the graupner pumps, as it would require trying to fill in the hole around the inlet pipe.

Thoughts.

andy

[ChrisBParticipant @chrisb29081]

you can get one way valves at pet shops which have aquarium supplies, they are for air lines, to stop water syphoning back to the air pump, but I would think they would work with water (reversed) If you decide to go that way.

Chris B

[Andy CParticipant @andyc56856]

Okay so on the back of today’s boating, which was a great morning, I have tried some other things. Without the hoses connected it will fire both sides using forwards and backwards on the viper marine esc. However when I take it of the bucket of water to connect the hoses it stops working again. It will not squirt at all once you do this.

I still think it needs some water in it to work properly. So just means I will have to prime it pond side beforehand.

Unless anyone has any ideas.

Andy.

[Trevor Drabble 1Participant @trevordrabble1]

Andy , My suggestions would be that you first of all position your pump as low as possible within the hull then install a forwards facing water intake about 3mm behind the prop and also about 3mm below top of its arc so that water is then driven up the intake to a small vertical sealed cylindrical container , about 30mms diameter by 40mms tall sited level or slightly higher than pump , with 2 tube connections in the lid ,with the water feed being connected to the one that terminates just under the lid . The pump is then attached to the other connection , the tube of which extends to within about 5mms of the bottom of the container . In operation then , once the container is filled with water under pressure from the prop the resultant positive pressure within the container helps drive the water to the pump . Since in subsequent operation there will always be water in the container , and the pump intake is below the water level you should have no further problems . Trevor.

[Paul TParticipant @pault84577]

Andy

Sorry to say it but I think the best option is to change the pump to a self priming version.

Paul

[Andy CParticipant @andyc56856]

Thanks guys. I had a look at other pumps. Even the graupner item is not self priming and it is sold for this particular purpose. I have made a modification that I hope will work. Will have to make another trip to the pond tobtr6bit out. Oh well. Not all bad, as long as the sun is shining.

Andy

[Malcolm FraryParticipant @malcolmfrary95515]

If the pump is below the waterline it should flood itself when the boat is put into the water. On my lake, which is salt water, it is never a good idea to leave water in the system. Quite possibly much the same for other lakes. Washer pumps in cars usually sit with water plus screenwash fluids, which should contain corrosion inhibitors.

[Andy CParticipant @andyc56856]

So, the saga of the non pumping pumps continues. At the lake on Sunday once again nothing. So, change of plans. Bought a Graupner pump, like that fitted in Richards pirate ship (working very well by the way, as the wet kids on the dock will attest too). New bit of pipe and an inlet. Inlet is tiny but seems to be a match to the pump and pipeworts. So should work. The question I have now is how do I fill the massive great big hole in my hull. I was thinking using an appropriate sized hole saw to cut a plug and glue it in. Bit of filler and some sealing etc and it should work. Shouldn't it? Any other options. Not really wanting to replace the whole hull bottom as the motor mount and rudder are all fitted and aligned.

Cheers in advance

Andy

[Charles OatesParticipant @charlesoates31738]

I would glue a plate of wood over the inside of the hole, and when it's dry use filler from the outside. Sand, paint and it should be fine.

Chas

[Andy CParticipant @andyc56856]

Posted by Charles Oates on 04/10/2018 12:00:26:

I would glue a plate of wood over the inside of the hole, and when it's dry use filler from the outside. Sand, paint and it should be fine.

Chas

hmm. That's a good idea. I could use both ideas. Plate it from the inside and stick the plug to the plate. fill the edges of the plug and paint. A bit of Cap'n Tolleys crack sealer would not go a miss either.

With the graupner pump does it matter which way up it is fitted. looks like, from the writing, it should be fitted upright.

Thanks Charles

Andy

[ashley needhamParticipant @ashleyneedham69188]

Andy. It is only a landing craft. Cut a bit of 4mm plywood to patch over the hole, use PVA and paint after. Ashley

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