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View Full Version : ive got the hump !!!!!



stevie welsh - n/a
2-Dec-06, 07:14 PM
:)hi everyone .please help us



weve had a marlin flying fish for about 5 months now and weve <font size="4">[/COLOR]been allover the coast at fleetwood and blackpool having a scream !!! after numerous attempts to start from a dead stop on water with two people in all weve managed to do is get wet and look like plonkers !



can anyone give us some hints as to how to get it to lift effectivly or is there anyone in the blackpool area that could show us ? venue to suit u .

weve tried the instructions that we got from flying fish but we get nowherevfast and have to limp back to the beach and get a run up to stay up on the cushion!!! were both around 14 stone ,are we to fat or could there be something wrong with the craft its self ?? the back end seems to drag quite a lot when were trying to get it to lift .



im ready for sending it back !!!!! best response wins a prize !!<font size="2">[/COLOR]



please help !!!



steve and stevie

Derek Sweetman - n/a
3-Dec-06, 09:11 AM
Getting over hump from a floating start.

First lets state whats happening!

All your skirts are full of water the open segments at the front and sides will drain the easiest, the chipbags at the back the slowest.

<font color="orangered">If you give it full power the hole blown into the water will be big and you will flounder there in a rain of spray![/COLOR]

I've driven a Marlin two up (17 + 14 stone approximately)

1/3 throttle drain the skirt 30-40 seconds increase to half throttle get your weight forward driver leaning over the front the back will rise, lean slightly back increase to full power to accelerate up onto cushion and over hump.

It can help to slightly steer away from the wave you have generated.

Practice the technique one up as it will be easier.

Check the engine revs correctly so you know full power is available.



Derek Sweetman

Russ Pullen - n/a
3-Dec-06, 09:58 AM
What engines in it?

stevie welsh - n/a
3-Dec-06, 01:03 PM
hi russ thanks for your reply .



its got a rotax 503 i think . its only got 30 hours on and the revs max is around 4700.does the maximum revs give a guide to maximum power output ? im a bit green with engines and its possible it needs a tune .i was told by flying fish that the engine mixtures are self governed above idle ? im a bit green with engines and i hope its just my technique thats at fault !!



thanks



steve



http://hovercraft.org.uk/images/icons/smiley_icons/icon_eek.gif

stevie welsh - n/a
3-Dec-06, 01:07 PM
that sounds like good advise ,thanks



how do i go about checking the revs correctly ? ?



its got a rotax 503 (standard engine) and its the marlin 2/3 seat



have you ever managed it with 3 people a http://hovercraft.org.uk/images/icons/smiley_icons/icon_rolleyes.gif board ?

Ian Brooks - n/a
3-Dec-06, 07:42 PM
If its really 4700 rpm on a 503 then you are generating about 30hp, it should rev to about 6000 rpm static which will give you about 45hp... peak revs about 6500 which will get you nearer 50hp.



If the engine runs and starts well, then you probably need to adjust the blades a little.



Cheers

Ian

jon_curtis - n/a
3-Dec-06, 08:06 PM
might be a good idea, before you move anything, to have a quick clean of the carbs. make sure the jets are clear, has the engine been stood for a while? how do you store the thing. fuel lines clear/



those engines need a bit of fiddling to keep going good in a hover, more so if they get salty.the carbs will need checking for crud each time you go out.



if that dont work, do as ian says and have a fiddle with blade angle. pitching down all the blades the same (a little) will move the max rpm up.



you need to match the fan load to the engine.

Iceman - n/a
3-Dec-06, 08:40 PM
6000 rpm is too low, you need to set it to at least 6500rpm static, 6800 rpm max.



If you really are only getting 4700rpm, then restting your blades will transform your craft and getting over hump will take a few seconds each time!

stevie welsh - n/a
3-Dec-06, 10:53 PM
thanks for your reply but ive cocked up ! ive got it mixed up sorry ! its a briggs and stratton vangaurd .ooops



its run on the beach and probably has sum salt in .how do i get to the carbs and clean them ?? what should the revs max out at ?



wheres the best place to get a new air filter?



cheers steve

Sean Atterbury - n/a
4-Dec-06, 05:53 AM
http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif



What a thread, I realy enjoyed this one.



http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif



Take it slow like Derek said, can take up to a minute to get over, and if those pockets are still full of water then the backend will hop like you said, I have a 503 and mine does it too, OK I have home made skirts that do not drain as well but like you I have to take it slow on start up and after about 5 or 6 practice starts you will learn and get a feel for what the craft is doing and how much power to lay down. Funny that I find gettin over hump easier with two on than just me.



We hope that this year all will be sorted, I have fiddled with the skirts and will C if things go better, if not then it just takes a bit longer to get over, but over we will go.



Have a great Christmas.