Hitchcocks Forum

Over time, and probably enthusiastic tightening, I've managed to strip threads on the carb body. It's the ones for securing the float bowl to the body of the carb. I'm going to try tap them out a bit bigger but decided as I need wheels I'd get a new carb body. My old body is scoring the slider so I'll replace it for the moment and hopefully use the current one, re-tapped, as a spare.

Right my question: I'll start by saying that I have to take some sandpaper to the float bowl to flatten the surface of it tomorrow, it seems slightly warped at present. That's not the problem that has my head scratching though.

Basically I have the float bowl assembled, (but not on the carb body), and connected to petrol. As you'd expect the bowl fills with petrol and cuts the supply of fuel. I now have a bowl full of petrol. All very good so far. Now I carefully drop the carb body onto the float bowl and hold it secure. Press the tickler and the petrol overflows the carb. Now here's the problem when I release the tickler the petrol keeps flowing??? Remove the carb body from the float bowl. Petrol stops flowing.

I can's see any issue with the new carb body that I'm fitting the only thing in there that can effect the float is the tickler and it's recessed below the lip of the body. I confuses me that when I put the two parts together fuel remains cut off until I hold the tickler and then it won't cut off with release. Float must be getting jammed but there's not a lot in there to complicate things.

Any ideas more then welcome.

Hello there, JFW ---------Just to be sure as to what we are talking about, is this an AMAL Mk1 CONCENTRIC carb. ???? Which type of tickler (earlier or later) is fitted ??

Hi Alan R



Yes a Mk1 Concentric, sorry missed concentric from the subject. On the tickler Hmmm It's a new replacement body so I assume it has the new tickler? Its got a washer fitted over it on the inside to stop it coming out.

Make sure that the float is free to rotate on the spindle and that the gasket is not interffering with the float in any way.
You will have the later tickler as this has been standard fitment for about 30 years. I assume that if you do not depress the tickler and leave the fuel on for a few minutes it does not flood. (Just wondering if the tickler could be slightly too long and holding the needle of its seat a little)
Chevy

Hi guys------ CHEVY, re}--tickler holding needle off seat, yes that was my thinking as well. It's been known to happen when an old type tickler has been swapped for an upgrade kit (by old-type I mean where the button is inside a retaining bush assembly---a new-type being a large, external aluminium sleeve with a rounded top to it. )---JFW, when you say---------"a new carb. body" is that a brand new body or a 2nd. hand body that is new to you ???

I've had to extend a couple of ticklers because they take 15 mins to fill up but haven't seen one too long and this sounds like it might be the problem

Norm: You say you have had to extend a couple of ticklers as it took "15 mins" to flow the carb. This is also a problem with my Concentric mkI. If not 15 minutes, at least 25 seconds and of the bike has been standing for a long time, I sometimes have to take the float bowl off and "give the float a kikc" to get the petrol flowing. .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

1. How did you extend the tickler? .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

2. Can it be that my float needle is sticking in place and needs cleaning or replacing? .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

I must add that once I manage to flow the carb and start the bike, it will run just fine all day. I have also checked the petrol flow into the carb. It is more than sufficient. .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

Regards, Anders F. R.

Hi Anders, 15 mins is probably a bit over the top but I used to suffer sore finger syndrome and would have to swap fingers till it finally filled.I ground down a piece of wire till I could get it to a press fit up inside the existing tickler nice and tight and then cut the end off about 2mm longer that the original. Might need a little tweeking after but that will be obvious if the fuel keeps running but on the ones I have done this hasn't been a problem