74 Commando Boyer Testing

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MarkDeaton said:
Is that what the click is during kicking. After a couple of kicks there is an audible click and seems to be about a 1/4" jump in the kick lever like it is jumping past a notch if that makes sense.
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Be sure it isn't the KS clamp splines slipping and being distorted. Sometimes the clamp bolt loosens and can just be re-torqued. Sometimes no amount of torquing will make for better clamping as the splines closest to the bolt are at their limit. There was several old recommendations in other threads to grind off those last one or two splines of clamp to permit everything to close up tighter. Some even replace the bolt with a high tensile through bolt and nut.
 
I am trying to post a picture but I am using my
phone and there are a bunch of commercials and advertisements popping up. The X to close them is really little and I keep accidentally launching the commercial.
 
MarkDeaton said:
I am trying to post a picture but I am using my
phone and there are a bunch of commercials and advertisements popping up. The X to close them is really little and I keep accidentally launching the commercial.
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You can become a VIP member to remove the ADs. It also lets you attach files, pictures directly to the reply box rather than have to link to them on an external hosting site. Much more convient.
 
Static timing is set at full advance. When kickstarting the ignition is (or should be) fully retarded.
L.A.B. said:
Boyer "black box" Micro MkIII is, Micro MkIV isn't (although this could well be a MkIII box).
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What does full advance and fully retarded mean?
 
MarkDeaton said:
What does full advance and fully retarded mean?
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When kickstarting and at low RPM the spark occurs much closer to TDC and that's 'retarded' (so fully retarded for kickstarting).

As engine speed increases the spark occurs earlier so 'advances' until it reaches 'full advance' (31 BTDC for the Boyer although the Boyer MkIII and MkIV don't completely stop advancing as some do and Pazon Sure-Fire actually retards slightly above 5000 RPM).

74 Commando Boyer Testing


Note that the mechanical auto advance unit (AAU), analogue (Sure-Fire etc.) and digital (Altair, Tri-Spark, etc.) electronic advance curves have different advance characteristics.
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Finally got it sorted. Put a bit of gas in the cylinders and heard it purr for a brief moment. Put some fuel line on both carbs, poured in a tad of gas into the lines and it dripped right out of the bottom of the carbs. Lo and behold the screws that go on the bottoms of the bowls do not exist. And clues on replacements?
 
MarkDeaton said:
Finally got it sorted. Put a bit of gas in the cylinders and heard it purr for a brief moment. Put some fuel line on both carbs, poured in a tad of gas into the lines and it dripped right out of the bottom of the carbs. Lo and behold the screws that go on the bottoms of the bowls do not exist. And clues on replacements?
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Widely available. Amal carbs used on other brands.
 
MarkDeaton said:
Finally got it sorted. Put a bit of gas in the cylinders and heard it purr for a brief moment. Put some fuel line on both carbs, poured in a tad of gas into the lines and it dripped right out of the bottom of the carbs. Lo and behold the screws that go on the bottoms of the bowls do not exist. And clues on replacements?
Click to expand...
Do you mean the two small screwdriver screws holding the bowls onto the carb bodies? If missing what is holding the bowls up?
Sounds like you need to take carbs off and check them over fully. Replace gaskets and confim what needle position is, what jets are present, needle type, float level positions, float needle type and condition. All items need to be in proper setup for these carbs.

There are rebuild kits for these carbs with all new gaskets, needles, float valve needles and O-rings. See your faav supplier or chexk out Classic British Spares, EuroJumbalya, etc.
 
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