My Triumph Classic Story: carburetor

Showing posts with label carburetor. Show all posts

Tuesday, 30 October 2012

Float Chamber

Float Chamber

(a) Loosen the screws securing the float chamber ensuring that the float chamber will not drop once the screws are removed. If necessary tap the float chamber lightly with the handle of the screwdriver to break the gasket seal. Keep the float chamber level as you remove it to stop the float mechanism from falling out.
(b) Carefully separate the float chamber gasket from the body or float chamber.

Amal Mark 1 Concentric Carburetter

Notes On Rebuilding the Amal Mark 1 Concentric Carburetter

The Amal Mark 1 Concentric carburetter was introduced onto motorcycles during the 1967 model year. A lighter and more compact carburetter than the preceding Monobloc the name derives from the design of the float chamber around the main jet, an arrangement intended to reduce the effect of fuel surge in the float bowl under cornering and transient throttle conditions.

The carburetter is currently available in two body sizes; the 600 Series in 22mm, 24mm, 26mm and 27mm bore sizes and the 900 Series in 28mm, 30mm, and 32mm bore sizes. A 1000 Series Concentric in 34mm, 36mm, and 38mm bore sizes was dis-continued during the 1970s.

Mark 1 Concentric carburetters are available in 4 Stroke and 2 Stroke configurations and can be left or right handed depending on the position of the tickler mechanism and adjusting screws.

Removing Carburetter

Carburetters should be removed and replaced onto the bike as complete units, with mixing chamber tops and float chambers attached. Failure to do so increases the possibility of warping of the carburetter flange and body.

(a)   Run the engine with the fuel taps closed to empty the fuel from the carburetter, or drain the float bowl by removing the float chamber drain plug.
(b)   Loosen the fuel banjo bolts and remove the banjos.
(c)   Remove the plastic or bronze fuel filters from inside the banjo.

(d) Loosen the carburetter mounting nuts evenly. Take care not to jam or stress the flange on the studs by turning the nut on the tickler side of the body back too far in relation to the other nut.
(e) Remove the nuts and slide the carburetter off the mounting studs.

INFO FROM HERE
http://www.amalcarb.co.uk/TechnicalDetail.aspx?id=11

Sunday, 28 October 2012

MY PHOTO CARBURETTER

Replacing the carburetter

Always replace the carburetter fully assembled with the float chamber and mixing chamber top attached. The manifold flange and any heat reducing spacers should be carefully checked and dressed if necessary to ensure they are flat. Bolting the carburetter to a distorted flange or uneven spacer increases the risk of carburetter body or flange distortion.

Mark 1 carburetters are not designed to bolt tightly to the intake flange and may distort if overtightened. It is only necessary to compress the O ring seal to ensure air tightness. When correctly tightened the carburetter flange and engine manifold should be just touching. Nyloc nuts should always be used to mount Amal Mark 1 carburetters and should be tightened to no more than 4 ft lb.

Ensure that throttle and choke cables are able to open and shut freely when the petrol tank is replaced on the bike, and

JETS

Jets

Needle Jets are best replaced as a matter of course especially if the age of the jet is unknown. They are the most vulnerable of the jets to wear with only .001” between sizes and a worn jet will cause very rich running between 1/4 and 3/4 throttle opening.

Replace the needle if there are signs of wear or corrosion, particularly on the parallel section. Check that the needle clip grips the needle securely and is not distorted in any way. The split in the clip is part of the design.

JETS

ADJUSTER
TOP
THROTTLE SPRING
NEEDLE CLIP
JET NEEDLE
THROTTLE SLIDE
MAIN JET
THROTTLE STOP
AIR SCREW
ABUTMENT
NEEDLE JET
MAIN JET HOLDER
FLOAT
BANJO BOLT
BENJO
FLOAT NEEDLE
FLOAT SPINDLE
AIR VALVEGUIDE SLEEVE
AIR VALVE SPRING
AIR VALVE
TICKLER
TICKLER SPRING
DRAIN PLUG

CARBURETTER FUNCTION

CARBURETTER FUNCTION

CARBURETTER FUNCTION

The petrol level is maintaineed by a float and needle valve and is nocircumstance, should any alteration be made to these parts. In the event of a leaky float or aworn needle valve, the part should be replaced with new.
( Tips from TiranaAduka do not attempt a grind a needle to it's seat)

The petrol supply to the engine is controlled, firstly , by the main jet and, secondly by means of a taper needle which is attached to the throttle valve and operates in a tubular extension of the main jet.

The main jet controls the mixture fron three-quarters to full throttle, the adjustable taper needle fron three-quartes down to one-quartes throttle, the cut awat partson of the intake side of the throttle valve fron one-quater dwon to about one-eighth throttle, and a pilot jet having an independently adjusted air suply, takes care of the idling fron one-eighth throttle down to the almost closed position.

These various stage og control must be kept in mind when any adjustment is contemplate.
With the standart setting it is possible to use nearly air in all conditions, except.perhaps , when the engine is pulling hard up hill or is on full throttle , when some benefit may be obtained by slightly closing the air control. Weak maxture is always indicated by popping or spiting at the air intake.
A rich mixture usually causes bumpy or jerky,running and, in cases of extreme richness, is accompanied by the emmision of black smoke from the exhaust.