Amal carb setup

guest76

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My Dad has just got a new bike, and we are trying to setup the Amals

We have a pair of MK1 concentrics both setup the same.
Just replaced the floats, as one of the old plastic ones had a crack and had sunken.

So two new genuine stay-up floats with the aluminium Viton tipped needles to match.

We have setup as per the Bushman guide, and all is running fine (bike runs great, sounds perfect, and throttle pickup is nice)
However, on the right carb when you snap shut the throttle, fuel leaks out of the tickler.
Both floats were setup at the same height, and the left one doesn't do this.

We tried swapping the entire bowl from left to right (putting the left one that didn't leak on the rightside)
And the problem stayed with the right carb, not with the float.

We have checked the slider height, and these are both identical.

Looking to you guys for ideas...

Thanks in advance!!!
 
thanks JD

it's actually a very late Dominator 650SS

the setup is as per the early commandos (i.e. the recommendation by the Norton Owners club, and guides from the INOA are the same)

I am looking to you guys, as you have a million more ideas than the stuffy club forums.
oops... did I just say that out loud ;-)
 
When you say "fuel leaks out of the tickler", how much fuel? Is it a constant stream indicating a stuck needle, or just a drop.
 
The commando head/port is tilted forward at 39 degrees the curved manifold brings the carb back to 10 degrees.
On a featherbed, with a SS semidown draught head the head port angle, therefore the carb is 18 dergees.

The old float 622-069 is not 100% immune to fuel level change due to carb tilt. Not having personally tested stay up floats, it remains to be seen how the fuel level is affected by the steeper carb tilt of the featherbed bikes with the SS head.

Here is a thread that got virtually no response ............
http://www.accessnorton.com/amal-fuel-level-tube-tool-t20180.html

Yet yesterday, by using my fuel level tool I was easily able to diagnose a float that had very low buoyancy, therefore an incredibly HIGH FUEL level which over flowed. A new float and a move of the brass seat and all was well.

With a featherbed your problem is exaggerated.
 
Re: Amal carb setup forum recommendations?

the setup is as per the early commandos (i.e. the recommendation by the Norton Owners club, and guides from the INOA are the same)

I am looking to you guys, as you have a million more ideas than the stuffy club forums.
oops... did I just say that out loud ;-)

NOC?
Did you go to the forum? or to the tech section.
Their tech section content is very heavily taken from the old forum(now closed), which IMO is/was incredibly poor... in the areas I have looked.
 
Check the viton needle seat in the carb that leaks for bad spots. It may appear to maintain a float level, but when the bike is running the vibration lets it leak. Just a thought. I had to re-grind one of my seats and it appear OK now.
 
Sounds like your float might be sticking on the bowl gasket.
The gaskets are cut a little generous and can cause float sticking near the pivot pin.
If so this can be carefully trimmed back with an Exacto knife.
 
When snapping throttle shut, there is a deceleration, and fuel sloshes forward, rising to a higher level on the forward side of the float bowl. Maybe this has something to do with it.

Since swapping bowls keeps problem on right, look at carb body for possible problem/solution.

Slick
 
dynodave, the NOC site is a great place to go these days if you want an argument about how wonderful the Manxman is... such a shame it's come to that, as it used to be a good resource :-(

the brass seat was something we first thought needed more investigation, as was the way the Viton tipped needle seated.
however, by swapping the bowl, float and needle from right to left and the problem staying on the right side ruled this one out.
if the issue was related to the float height or needle seating I would have expected the issue to transfer from right to left.

the tickler length is not something we'd considered, and we'll go down the garage and measure this now!

@slick the bike is on the stand when we see this, so no movement-related issue with fuel sloshing around in the bowl.

thanks!
 
gtiller said:
it's actually a very late Dominator 650SS
Click to expand...

As it isn't a Commando, this thread will be moved to the 'Other Nortons...' section, shortly.
 
Sounds like you are approaching the normal causes of the fuel level being too high. Another that can cause it is if the float spindle p/n 622/071 is not seating properly in the fuel bowl slot.
 
RESOLVED = thanks all that responded with great ideas!

The difference in the wasted part (groove) of the needle valve on the aluminium (aluminum) versus the plastic one was the cause of the differences.

Seems there is much more slack on the new style alloy one.

Bike is now running sweet.

LAB - I know its a dommie, but I posted in the commando section as the response is always much better, and they are almost the same ;-)
Sorry - i'll play fair next time!!!
 
L.A.B. said:
As it isn't a Commando, this thread will be moved to the 'Other Nortons...' section, shortly.
Click to expand...

Oh, come on. It's an Amal topic, a respectable and acceptable off shoot.
Are ya gettin a little itchy? It's been awhile, hasn't it. Go ahead and sap this post if it will give you a fix.
 
@pete rules is rules ...I'll sit on the naughty step for five minutes, then we're all good! LOL
 
pete.v said:
L.A.B. said:
As it isn't a Commando, this thread will be moved to the 'Other Nortons...' section, shortly.


Oh, come on. It's an Amal topic, a respectable and acceptable off shoot.
Click to expand...
Click to expand...

Mmmm? :? .................No. :wink: It's Other Norton Amal. :)
 
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