Fuel level for Amal MK1 Premier

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I agree, I dont think the measurement takes any tilt into account......which gets us back to the question.......is there a method to set the float height or fuel level with the carbs fitted to the bike (tilted) which takes this into account?

Mick..........kettle738
 
The place where the fuel level is important is at the spray tube. If you set the fuel level with the carb upright, the fuel level at the spray tube will remain exactly the same when you tilt the carb by 10 degrees as the spray tube is in the centre of the carb.
ando
 
Giving that last comment some thought........"If you set the fuel level with the carb upright, the fuel level at the spray tube will remain exactly the same when you tilt the carb by 10 degrees as the spray tube is in the centre of the carb."

If that is correct, and I see no reason why it shouldn't be, then the point to measure the fuel level by the clear plastic tube method (see LAB photo) would be at the centre of the carb as viewed from the side .....no?

In any event I think I will try that as it seems to make sense to me.

Mick.................kettle738
 
ando said:
The place where the fuel level is important is at the spray tube. If you set the fuel level with the carb upright, the fuel level at the spray tube will remain exactly the same when you tilt the carb by 10 degrees as the spray tube is in the centre of the carb.
ando
Click to expand...

I had never thought of it that way, but now that someone has said it, it makes complete sense.

I've worried about any part but setting the float height as recommended.
 
A note to the anal retentive/perfectionists: remember that these bike were made poorly in England by unenthuastic workers using obsolete manufacturng equipment, an antiquated design with low cost and low quality electric parts, and questionable carbs. Since new, many have had shoddy work by "mechanics" and often poorly maintained. It is easy to improve on just about everything on a Commando, but no need to go overboard.
 
Phil Vincent attemped to build "a long lasting" machine,infact the bike had reached a point where it could not be improved , also the vincent owners where a differant breed, they lavished time and care.... that killed it off! But you hit the nail full on the head...Poorly maintained, thats the key..this ensured a nice steady sale of spares
I cannot dream that the norton was made to last 40 years! "buy one trash it, buy another" Norton "built in" short lived parts, I still think the oiling system is rubbish.
How long after a start doe's the oil run back down the the push rod tunnel and onto the followers? 2-5 minutes? the manual shows splash return feed .
Once the system is "primed and up to speed" its OK, but when a machine as stood a week/month theres a dry lull. I agree modern oils have a good film strength, but dip a hot part in hot oil and hang it up for a week,then check the results, But lets not start another oil thread.




christulin said:
A note to the anal retentive/perfectionists: remember that these bike were made poorly in England by unenthuastic workers using obsolete manufacturng equipment, an antiquated design with low cost and low quality electric parts, and questionable carbs. Since new, many have had shoddy work by "mechanics" and often poorly maintained. It is easy to improve on just about everything on a Commando, but no need to go overboard.
Click to expand...
 
Yes, Now thats what i have been saying, "Norton built in early failure idea's" doe's it take a rocket engineer to place a oil bath around highly stressed item?
Why is the oil dumped into a timing case, dump it into the push rod tunnel, bags of lube drowing the followers...cushty!

DogT said:
Did you see ludwig's cam oil trough?

Dave
69S
Click to expand...
 
I know this is an old thread, but I am having the same issue installing my new Premiers.

The fuel height came at about 8.5mm and the float was pretty flush with the top of the bowl when first checked.

The platform the float needle recesses into is about 5mm, so in this first picture the level is about 6mm. But as you can see in the second, the float is way too high.

Not sure how to get this in spec with the float lower?
 

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gortnipper said:
The platform the float needle recesses into is about 5mm, so in this first picture the level is about 6mm. But as you can see in the second, the float is way too high.


Not sure how to get this in spec with the float lower?
Click to expand...

Are you checking with the float pivot pins clamped down into the bowl slots? If not, the float heights/fuel levels won't be accurate.
There are two ways to adjust the float height/fuel level, either by adjusting the tang on the float or by adjusting the height of the needle seating in the float bowl, but before you do that I suggest you make a note of the exact measurement from the gasket flange to the bottom of the seating.
 
Here is what I use. Small piece of angle aluminum to hold float pivot pin in place when checking level off of bike. Old drain plug with a MIG tip threaded in and a piece of fuel line to check fuel level while in situ.
 

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L.A.B. said:
Are you checking with the float pivot pins clamped down into the bowl slots? If not, the float heights/fuel levels won't be accurate.
There are two ways to adjust the float height/fuel level, either by adjusting the tang on the float or by adjusting the height of the needle seating in the float bowl, but before you do that I suggest you make a note of the exact measurement from the gasket flange to the bottom of the seating.
Click to expand...


I have simply adjusted the tangs to move the float height. I am unsure as to what difference adjusting the needle seat instead would make, since the pivot point and target level are fixed?

(Sorry, gortnipper, it seems I inadvertently deleted some of your message text by mistake - L.A.B.)
 
L.A.B. said:
I have simply adjusted the tangs to move the float height. I am unsure as to what difference adjusting the needle seat instead would make, since the pivot point and target level are fixed?
Click to expand...


Adjusting the seating was the original method of altering 'float height' (with the old type non-adjustable white plastic floats).

http://www.jba.bc.ca/Bushmans%20Carb%20Tuning.html
Fuel level for Amal MK1 Premier
 
gortnipper said:
L.A.B. said:
Are you checking with the float pivot pins clamped down into the bowl slots? If not, the float heights/fuel levels won't be accurate.
There are two ways to adjust the float height/fuel level, either by adjusting the tang on the float or by adjusting the height of the needle seating in the float bowl, but before you do that I suggest you make a note of the exact measurement from the gasket flange to the bottom of the seating.
Click to expand...


I have simply adjusted the tangs to move the float height. I am unsure as to what difference adjusting the needle seat instead would make, since the pivot point and target level are fixed?

(Sorry, gortnipper, it seems I inadvertently deleted some of your message text by mistake - L.A.B.)
Click to expand...

Yes, I made sure the pivot pins were seated into the slots.

I understand there are two ways to adjust the height of float, but am unable to see any mechanical advantage to be gained by adjusting the seat height vs. the tangs?

I guess if no one can point me true on this, I will drop Amal a note.
 
I queried Amal about the whole float level/tilt issue on the commando, reply I got was that the tilt of the carb is irrelevant as the fuel level at the center of the bowl remains the same (parallel with the ground) and that's where it matters... just reporting what they said.

My 2cents: get the floats to 1mm above flange surface (where the needle just shuts off the fuel) and tweak as needed from there
 
When I did the u-tube method I set the desired fuel level at the middle of the bowl. If you move the u-tube to the front of the carb, the fuel level comes pretty close to the top of the bowl. You will know if the float is fouling the base of the carb body as gas will leak out the tickler.
 
gortnipper said:
I understand there are two ways to adjust the height of float, but am unable to see any mechanical advantage to be gained by adjusting the seat height vs. the tangs?

I guess if no one can point me true on this, I will drop Amal a note.
Click to expand...

As L.A.B. said, the only way to adjust the float height with the old white plastic floats is by re-positioning the brass seat. The tang on these floats is plastic and it just springs back if bent. Bushman's carb tuning tips are really good.
 
Here is what the fuel level looks like at the front of the bowl compared to the center. I have the top of float set so the end opposite the pivot is flush with the top of the bowl without a gasket. Bike was on center stand when these pictures were taken. A couple of things I found out about the Stay-up floats. When you bend the tab it is possible to compress the pivot pin hole causing it to bind. If you press on the tickler too hard I think it is possible to bend the tab, that is the only reason I can come up with that would explain how the level changed in one of my carbs.
 

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Deets55 said:
When you bend the tab it is possible to compress the pivot pin hole causing it to bind. If you press on the tickler too hard I think it is possible to bend the tab, that is the only reason I can come up with that would explain how the level changed in one of my carbs.
Click to expand...

Thanks for this idea. I was careful to bend the tab before the tangs. I will check to make sure that the "elbow" I created doing so does not bind on the carb body.
 
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