Car starts well cold; often difficult to start hot; coughs and splutters and tends to stall; throttle works normally and car goes well; can generally be kept running at low revs by means of the choke, but tends to cut out.
Jets
A clogged pilot jet is usually responsible for erratic engine idling. Erratic engine operation in the medium and high-speed ranges and during acceleration is often accounted for by a clogged condition of main jet, main air hole or hole constructions in the carburetor body.
Wash the jets clean. Wash the holes in which jets are located, and clear each hole by directing compressed air into it, thereby removing foreign matter, if any. (I used a bicycle pump with football attachment, and also blew air through all the holes in the jet)
I'm finding that the jet has a very narrow adjustment range and is not easy to reset. Screw the jet all the way in and start the car; try to keep it running, if you can, and adjust the jet VERY slightly - you should hear the engine change and you'll quickly get a feel for how little movement is required.
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| Secondary Pilot Jet - located at the front of the carburetor. | |||||||||||
| Primary Pilot Jet (the head just visible) - located at the rear of the carburetor. This is the one we're interested in. | |||||||||||
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| Below: primary jet (2) | |||||||||||
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not easily seen in this picture; the 2 holes on either side of the tip of the jet .
The threads |
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