Amal carb banjo fiber washers

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corich
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Amal carb banjo fiber washers

Post by corich »

My Silver Century Plus (WSPCL....) came to me with what looks, for all the world, like bits of leather sandwiched between wax paper to serve as the washers on the banjo fitting between the float bowl and the Amal twin-jet carburetor. Is this the original "fiber washer" or some resourceful previous owner's invention?

Regardless, they've seen better days, and I'm thinking I might do better with some fuel-resistant O-rings or copper crush washers or similar. Is there any particular favorite solution to this need?
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Oyster 49
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Re: Amal carb banjo fiber washers

Post by Oyster 49 »

If you talk to John at SOS he will be able to send you some correct washers.
andrew
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Re: Amal carb banjo fiber washers

Post by andrew »

I’ve tried O rings without success. Found you can’t get the bolt in tight enough to prevent it rattling loose without effectively squishing the O ring so much that it loses its seal.
corich
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Re: Amal carb banjo fiber washers

Post by corich »

That's helpful to know about the O-rings squishing out, Andrew. Thanks.

I'd happily order new washers from John, and probably should have included them in my last order from him. Unfortunately, I'm in the USA and our Customs agency is slowing imports down pretty badly right now. I was hoping to fire this motor up for a trial this weekend, so I'd like a functional replacement that I can find at my local hardware or auto parts store, if that's possible. I might just try crush washers and see if they seal....
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Oyster 49
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Re: Amal carb banjo fiber washers

Post by Oyster 49 »

If you are in the US, try any classic motorcycle dealers, or even look on ebay. Don't overtighten the banjo bolt, the threads in the carb body can easily strip out.
andrew
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Re: Amal carb banjo fiber washers

Post by andrew »

I’ve had limited success with nylon washers, which are readily available at Home Depot etc. Some aren’t pliable enough to seal but others are OK for test runs etc. Getting right size can be tricky, and really have to check that they don’t leak and that the material they’re made of is safe for gasoline applications.

I took the banjo bits to the store and tried them on until I found one with the right inner diameter.

Definitely want to get the proper fibre ones from John though, they seal perfectly and last ages without having to worry about bolt coming loose etc.
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Charles uk
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Re: Amal carb banjo fiber washers

Post by Charles uk »

Gentlemen your missing the whole point of the float chamber, it's there to establish a fixed level for the fuel below the main jet.

Change this with the wrong thickness washer & you could well alter the fuel/air ratio a small amount.

Fibre washers of the right diameter/thickness cost cents pence!
Make it idiot proof and someone will make a better idiot.
corich
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Re: Amal carb banjo fiber washers

Post by corich »

@Oyster, agreed - one of my biggest concerns with copper crush washers is that might require too much torque, and the carb body would strip out before a seal was achieved.

@andrew, I know that my local hardware shop has some composite washers, some nylon, some fuel-resistant O-rings... I'll sift through their stock and see what I can find.

@Charles, I agree with the sentiment regarding the sensibility of getting the correct parts. I'm certainly not a fan of the leather-and-wax-paper solution the previous owner seems to have invented. The only reason I'm considering other options is that my local lake will be closed for the winter before I can get anything from the UK again, and I'd really like to assess the condition of this just-purchased motor before I have to give up and pickle it for the season.
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Oyster 49
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Re: Amal carb banjo fiber washers

Post by Oyster 49 »

If you look around you will find in the US for sure. These parts are often common sizes used in different applications. You can even make your own from thick gasket material.
corich
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Re: Amal carb banjo fiber washers

Post by corich »

In the end, I decided to reuse the leather washers for now so I could at least try to run the motor in a bin in my back yard. She starts, idles, pumps a healthy stream of cooling water, shifts between neutral and forward, and revs just fine:
[YouTube] https://youtube.com/shorts/WE3wRz8o_Qw?feature=share[/YouTube]
I will need a handful of small parts from John before next season - the fuel shutoff is leaking, the throttle cable is in poor shape, and there are the banjo washers still. I'm sure I can think of a few more items if I put my mind to it....
Sandro Picchio
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Re: Amal carb banjo fiber washers

Post by Sandro Picchio »

The fuel tap leaking might be fixed by removing the cork part and boiling it in water.
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