amal carb advice needed

Having problems with a Seagull? - ask an expert here

Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo

Post Reply
tedrevive
Posts: 6
Joined: Sat Mar 02, 2013 8:57 pm
Location: wiltshire

amal carb advice needed

Post by tedrevive »

I have a 1977 silver century with a two jet Amal carb. It starts and runs very nicely untill the longer second jet comes into play, then I am obliged to use the choke flap to keep it running. The jets are both clear, the carb is clean and the fuel filter is in good order. Any advice? Also, on which side of the carb body should the float bowl be mounted? When I got the engine, it was on the 'tank side', the manual says 'boat side'. I looked at switching it but it seems it might foul on the transom bracket. Any advice will be greatly apriciated. All the best to you from Ted
Horsley-Anarak
Posts: 2838
Joined: Thu Aug 07, 2008 8:42 pm
Location: Surrey

Re: amal carb advice needed

Post by Horsley-Anarak »

Float bowl should be on the boat side, on this engine.

Image

Take the fuel pipe off the bottom of the carb and open the fuel tap, use a jam jar to catch the fuel.

There should be a steady stream of fuel that does not diminish. This proves you are ok from the tank to the carb.

Have you checked the filter in the bottom carb bolt?

Does the fuel bowl overflow when you tickle the little button?

H-A
tedrevive
Posts: 6
Joined: Sat Mar 02, 2013 8:57 pm
Location: wiltshire

Re: amal carb advice needed

Post by tedrevive »

Hello there HA, all the fuel is flowing nicely,tap and tickle. Banjo gauze is nice and shines after a soak in salty viniger(rinsed and dried). Could it be float level? Currently there is 6mm travel on the float. Does the float bowl orientation make much difference beyond looking original? Thanks for your time, all the best from ted
User avatar
Stelios_Rjk
Posts: 1458
Joined: Sun Jun 17, 2012 10:15 pm
Location: Athens - Greece

Re: amal carb advice needed

Post by Stelios_Rjk »

In the float bowl there is a needle that gets through the floater. On the needle where the floater is attached there is a gap. You could check this if it is standing there correctly. The gup is there for the wires of the floater to mount on.

Please see the pics, I may not describe it in the correct way. Where the pencil points is the gap.

About the orientation of the float bowl I don't think there is a matter. It has happened to run my engines trying both orientations and there was no difference.

Image

Image
I love the 10600/145 turns!!!
tedrevive
Posts: 6
Joined: Sat Mar 02, 2013 8:57 pm
Location: wiltshire

Re: amal carb advice needed

Post by tedrevive »

Say, that's a nice float. Mine's a nylon one. And lovely clear pics.
The floats located on the needle ok. That's the thing, everything looks good and seem in order, only the results are disappointing. Starvation is certainly the issue though, tickling the carb while on an open throttle lets the engine pick up. Tomorrow I'll try having the float a little above the needle notch. Thanks again for being so helpfull, it's great having other gull fans to bounce off :)
chris
Posts: 548
Joined: Mon Mar 06, 2006 3:13 am
Location: clontarf aus

Re: amal carb advice needed

Post by chris »

I would try cleaning the carb again, use compressed air to clean the jets, don't change the float setup, it will cause the motor to run erratic, I have had carbs that I thought I had cleaned and had to do it again.
User avatar
Charles uk
Posts: 4972
Joined: Wed Feb 27, 2008 4:38 pm
Location: Maidenhead Berks UK

Re: amal carb advice needed

Post by Charles uk »

When they say clean the carb, they mean everything from the fueltank to the jets.
Make it idiot proof and someone will make a better idiot.
tedrevive
Posts: 6
Joined: Sat Mar 02, 2013 8:57 pm
Location: wiltshire

Re: amal carb advice needed

Post by tedrevive »

Right so, I've been all through the system again and thoroughly cleaned the tank, tap fuel line, gauze filter, jets etc. But no success. It still is being starved on the long jet. I noticed the seam on the plastic float has worn a groove on the inside of the float chamber. Perhaps this is causing the float to stick up? I shall post again when I've had a go at it. Any other advice/ideas/experience of same greatly appreciated! All the best to you others in the merry seagull flotilla from ted
Horsley-Anarak
Posts: 2838
Joined: Thu Aug 07, 2008 8:42 pm
Location: Surrey

Re: amal carb advice needed

Post by Horsley-Anarak »

Have you got the longest jet nearest the inlet?

Image


Have you checked the compression, and looked for crankcase leaks?

H-A
User avatar
Stelios_Rjk
Posts: 1458
Joined: Sun Jun 17, 2012 10:15 pm
Location: Athens - Greece

Re: amal carb advice needed

Post by Stelios_Rjk »

What about the line that brings fuel from the float bowl to the banjo bolt? Or corrosion inside the float bowl. That could not allow the floater to move freely.
I love the 10600/145 turns!!!
User avatar
Oyster 49
Posts: 3318
Joined: Tue Oct 26, 2010 6:55 pm
Location: Derbyshire, UK

Re: amal carb advice needed

Post by Oyster 49 »

I had a very similar problem on an SD. It started well and ticked over normally, but when going down the canal on half throttle it soon ran out of steam and started to die. A quick push on the tickler sorted it out. In the end I changed the needle and float which seemed to fix it. The needle was slightly bent, and I suspect it was causing the float to stick in the up position.
Post Reply