My carb fell off. Oof.

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Nortorious

Nortorious

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Here's a new one (I think). I'm riding along and start to lose some power. Have to keep the rpms high. Still enjoying the ride and figure I'll just turn around and head home. I do a u turn and start dumping gas. A closer look and the two screws that hold the bottom of my Amal carburetor in place must have fallen out. I haven't touched them in over a year..

So now I'm waiting for the Uber and I guess I'll see how hard it is to get ahold of those screws. Advice and commentary welcome.
 

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Nortorious said:
Here's a new one (I think). I'm riding along and start to lose some power. Have to keep the rpms high. Still enjoying the ride and figure I'll just turn around and head home. I do a u turn and start dumping gas. A closer look and the two screws that hold the bottom of my Amal carburetor in place must have fallen out. I haven't touched them in over a year..

So now I'm waiting for the Uber and I guess I'll see how hard it is to get ahold of those screws. Advice and commentary welcome.
Click to expand...
Wow, both coming out, that seems crazy. It's difficult to see from the picture, but has the thread stripped?

Temporarly at least you could use nuts and bolts. If they are stripped maybe worth considering these...

 
I had similar event just few months back, same symptoms while riding along but the two screws coming loose were carb to manifold, not float bowl.
 
Lucky it didn't catch fire from spilling fuel out.

I replaced all the carb screws with Allen socket head screws, stainless set, from EuroJumbalya.
 
Thank you all! It looks like the Bonneville Shop in Colorado (near me) has the actual 622/086 screws so that is awesome. Going to pick those up now.

So you wouldn't use threadlock of any kind here right? Just asking for a friend..
 
Nortorious said:
Thank you all! It looks like the Bonneville Shop in Colorado (near me) has the actual 622/086 screws so that is awesome. Going to pick those up now.

So you wouldn't use threadlock of any kind here right? Just asking for a friend..
Click to expand...
Blue locktite should be fine. Helps avoid over tightening which can warp the bowls.
 
TBH that's why I wouldn't go down the allen screw route for these. Only room for a small screwdriver which helps negate the possibility of over tightening :-)
IMHO...
 
I used to have a commando engine in a wideline frame
The crank was re balanced but not enough
It used to shake those screw's out for a pastime
I had to drill and lockwire them in the end along with quite a few other fasteners
 
I was able to get the proper BA2 bolt and save it from the roadside. It still leaks gas but I was able to get it home (very ill advised) but basically a typical day on my Commando. Started off with a beautiful ride, something weird, and then an afternoon in the garage followed by gratitude that I didn't become a riding fireball today. Side note, the carb fell apart as I was doing a u turn in the fire department parking lot so I think the bike was dropping a hint.

I could still use help.. Here's a video of where it stands now. It's leaking pretty bad from the bowl. I'm about to investigate but any suggestions on what might be wrong would be really appreciated. I have to look at my Amal diagram but maybe I lost a gasket? Or put it back together wrong?

Video:
photos.app.goo.gl

New video by Michael Jefferies

photos.app.goo.gl photos.app.goo.gl
 
Is/was there a gasket between the bowl and the carb body?? I did zoom in on your first photos and wondered??
Bottom line, there should be, lack of will upset the the whole float/needle interface
 
Nortorious said:
Here's a new one (I think). I'm riding along and start to lose some power. Have to keep the rpms high. Still enjoying the ride and figure I'll just turn around and head home. I do a u turn and start dumping gas. A closer look and the two screws that hold the bottom of my Amal carburetor in place must have fallen out. I haven't touched them in over a year..

So now I'm waiting for the Uber and I guess I'll see how hard it is to get ahold of those screws. Advice and commentary welcome.
Click to expand...
This has happened to me, although I managed to get it before the screws fell out, also had the drain plug come out and once a main jet come loose and drop into the bowl, causing me to run out of fuel. The low strength loctite has fixed the problem so far.
 
When I screwed the bowl on by the roadside it was off kilter. I opened it up and found that the needle and float were not connected properly (see photo). I corrected this and put it back together. It is back to how it was this morning, which to be honest needed work so now I'm wondering what I need to do next with these..

There is indeed no gasket on either side. Either the previous owner removed them, or it's possible the last mechanic that worked on them just forgot but that's unlikely. It almost seems intentional with them both gone, but either way I think I need new gaskets.

@L.A.B. the previous owner may have done the Bushman's modification as you suggest, as they did a lot of good knowledgeable changes to the bike. I'm not sure if your note was calling out something that looked wrong. When I bought the bike, the local British bike shop put a different needle in it. This bike has always taken a lot of kicks to start, and then I have to hold the gas to get it warm. It's never fired up and idled nicely. I wonder if something isn't right.
 

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Nortorious said:
the previous owner may have done the Bushman's modification as you suggest, as they did a lot of good knowledgeable changes to the bike. I'm not sure if your note was calling out something that looked wrong. When I bought the bike, the local British bike shop put a different needle in it. This bike has always taken a lot of kicks to start, and then I have to hold the gas to get it warm. It's never fired up and idled nicely. I wonder if something isn't right.
Click to expand...

Firstly, the float needle groove should be in the float slot. Nothing looks wrong as such except for the lack of float bowl gaskets which is probably what caused the screws to drop out!

If the shop fitted different needles then that needs investigating. Edit: Also if the carbs have stepped or flat top spray tubes and various other settings. What are the L/H and R/H carb numbers (on the raised pads, 932/??)?

The lack of float bowl gaskets is probably the cause of the bad starting and poor idling.
 
Last edited:
I still have the original screws and spring washers on my Amals and have never had any problems with loosing bowl screws and if they did come loose the gasket would seep fuel, it always pay to check over your bike before any planned/long rides, I have had a manifold come loose once, was dark and 40 minutes from home just rode home on one cylinder, next morning tighten it up and was all good, not bad for over 46 years of ownership, but my Amals were replace back in 1982 and the last 10 years been running PWK carbs but the old Amal's are back on the Norton after a good service and clear the blocked pilot jet, slides are still good and new needles and jets.

Ashley
 
L.A.B. said:
Firstly, the float needle groove should be in the float slot. Nothing looks wrong as such except for the lack of float bowl gaskets which is probably what caused the screws to drop out!

If the shop fitted different needles then that needs investigating.

The lack of float bowl gaskets is probably the cause of the bad starting and poor idling.
Click to expand...
Thank you! Yes, I fixed the needle groove and float bowl already and that stopped the gas leak. I'll be interested to see how it improves after some new gaskets. Ordering now..
L.A.B. said:
Firstly, the float needle groove should be in the float slot. Nothing looks wrong as such except for the lack of float bowl gaskets which is probably what caused the screws to drop out!

If the shop fitted different needles then that needs investigating. Edit: Also if the carbs have stepped or flat top spray tubes and various other settings. What are the L/H and R/H carb numbers (on the raised pads, 932/??)?

The lack of float bowl gaskets is probably the cause of the bad starting and poor idling.
Click to expand...

The carbs are L36 932 and R36 932
 
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