Commander fuel leak

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H.Hundhausen
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Commander fuel leak

Post by H.Hundhausen »

Hello folksI havent posted anything here so far, so I will introduce myself first. I live in Germany and am adicted to rotary engines since almost fourty Years when I sa a NSU Ro 80 for the first time.I own almost any kind of Wankel engines, from the smallest OS 4,9cc to Mazda RX-8, where I have a shop now that overhauls these engines, but this is another story.I own a Norton Commander and an F1 Sport which I converted to the NRS 588 look, I loaded some pictures up some time ago.Now my problem: I have my Commander taken apart presently because I had an ignition problem, on side would not fire occasionally, I think it is a broken coil so I am about to replace both of them (the b ike has run about 56.000 miles so far).When I was doing this I saw that the bike started to leek fuel, but I couldnt find out where it ws leaking from. It dripped from underneath the exhaust, I could not find any traces on the frame or the engine.My question: Is it possible that one carburrettor overflows and the fuel finds it Way through the engine into the exhaust? Or does anyone have an idea where the leek could be?Regards Hans
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Richard Negus
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Re: Commander fuel leak

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Hi Hans,Welcome to the Forum!It is quite possible that you have a leaking fuel tap; take off the fuel pipe from the tap to check. If fuel is coming out, you can repair the tap with a kit of parts or, better, replace the complete tap.It is unusual for an ignition coil to fail; more often it is the Boyer ignition unit that is faulty or the engine suffers from lack of compression. The leaking fuel from the exhaust manifold is fuel that has not been burned.It might also be that the carburettors need overhaul. Replace the float needles with Viton-tipped type and don't forget the O-rings in the cold-start mechanism. They become hard with age and allow excess fuel into the engine.R.
Just a bike-less old fogey now. Boo-hoo!
H.Hundhausen
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Re: Commander fuel leak

Post by H.Hundhausen »

It might also be that the carburettors need overhaul. Replace the float needles with Viton-tipped type and don't forget the O-rings in the cold-start mechanism. They become hard with age and allow excess fuel into the engine.R.[/quote]Hello RichardI definetly have a problem with the coil, I switched the wires from the coils and again it was the same one that did´nt fire.The fuel leak started when the bike was sitting alone in the garage for some weeks, so it cant be unburnesd fuel.But as I have the fairing off anyway I will overhaul the carburettors, is there an overhaul kit available for them that includes the mentioned parts and possibly new gaskets?Also my waterpump seems to need an overhaul, would You suggest to send it to Graham at Startright? Its the 3rd time now for mya waterpump. isnt someone out there who can fix that problem forever??!!Thanks regards Hans
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Richard Negus
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Re: Commander fuel leak

Post by Richard Negus »

Hans,PM sent regarding carburettors and pump repair.I don't believe there's a permanent fix for the pump, except to replace it with an electric one, Davies Craig EWP80 for example.R.
Just a bike-less old fogey now. Boo-hoo!
gripper
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Re: Commander fuel leak

Post by gripper »

If your carbs have leaked fuel through the engine to the exhaust, that fuel has not got any oil in it and it will have washed any oil from the side faces of the chambers. I would inject some oil into the plug holes and turn the engine over backwards by hand to re-oil the working surfaces. Don't ask me how I know this.
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