Hi all,
I've got the follow issue with my Amal Monobloc 376.
Doesn't matter what i do the throttle stop screw doesn't do anything.
The engine doesn't react, No matter how far i screw in.
The idle is to low so it keeps stalling.
Hopefully someone can help me out what could be the issue.
Grtz Nick
is it the right screw? Ive got one on a B40 carb thats got the plain portion broken off. easily replaced from Amal.
Hi Chaz,
I've ordered all new screws fot this carb! That shouldn't be the problem!
Grtz Nick
i had similar problem with monobloc carb,
the slide can become worn at the point the idle screw touches it and the adjustment screw binds on the body of the carb allowing no adjustment, is the carb slide worn?
:D
Hi Derek,
also something i've thought about so i've replaced the slide as well.
No change... :-\
Grtz Nick
Does the slide move at all when the screw is turned?
my point was that slides are different and so are screws, the screw sits in an angled groove if one part is wrong it will not work corectly. you have new parts or have ordered new parts? working in a machine shop, parts do get machined wrong!!
my tale.....
I had a Transit for the business, ordered a part and when it arrived it was for a different model. I contacted seller and they sent another, this arrived also wrong. On contactng again they checked their stock location and it was correct, BUT someone in the stores had put the wrong part in the location SO they had to go through the lot to pull out and put in correct location before they got down to the correct part for me.
Mark, The screw doesn't lift the slide at all when i screw it in.
Might as well be what Derek I saying!
But I've compaired the old and new throttle stop screw and there was no difference! :-\
I think Chaz has probably got it right and because of tolerances, maybe it's a case of finding parts that work together.
My initial thoughts were that your spring on the adjustment screw is either too long or made of too thick material, so I just went to my garage and took out a carb that hasn't been touched for over 35 years (no exaggeration!) so it's never had bits replaced.
I was quite surprised that the throttle stop screw hardly does anything! It had to be wound in quite a way before contacting the slide; this would make it imperative that the spring be correct or slightly smaller.
Try removing the spring; does this fix the issue?
I've taken some measurements and will try to post some photos in a minute.
With the screw wound hard in, the distance should be 10mm.
The spring should be 12.5mm uncompressed.
The slide cutaway is 1mm, but mine will be a little worn.
I've tried to put pictures on but the image size police won't permit me to post.
Hi all,
I've found the problem.
A piece of polish paste was blocking the pilot jet resulting in fauling the jet so the bike couldn't idle.
Strange it didn't came out with ultrasone cleaning.
Thank you for the replies!
Grtz Nick