Solex Expert Level Question

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Rich Goold
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Re: Solex Expert Level Question

#16 Post by Rich Goold »

Phil, I disconnected the pump rods to try and help identify the problem. The quantities were also out of balance before the rods were disconnected. The problem is that on one carb
(for cylinders 3 & 4) cylinder #3 is at .6 while cylinder #4 is close to .8 . Both cylinders share the same accelerator pump. Accordingly I don’t think any adjustment would change the variance between #3 and #4

By the way, both cylinders on the other carb (cyl #1 and #2) match and also measure . 6.

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Martin Benade
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Re: Solex Expert Level Question

#17 Post by Martin Benade »

The linkage adjustment is the limiting factor, I think it’s unclear what the brass cylinders do other than maybe let the chamber refill faster.
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Martin Benade
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Re: Solex Expert Level Question

#18 Post by Martin Benade »

Aren’t there a pair of bosses on the side of the pump diagram housing with tiny metering orifices en route to the nozzles? Maybe one is too big, and could be soldered and shrunk a tiny bit. That would shift some flow away from that side and over to the other nozzle.
Last edited by Martin Benade on Fri Mar 17, 2023 6:41 pm, edited 1 time in total.
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Dick Weiss
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Re: Solex Expert Level Question

#19 Post by Dick Weiss »

Rich,

Carefully pull the injector(s) apart (they're a light fit) and DON'T lose the ball check: Use Stable to clean the tube
& the ball, Blow out the tube from its beginning, dry them, and add the ball (if you haven't lost it) & w/your mouth
blow-&-suck the injector to see/feel the ball check valve works; Aim the exit end to your face.

0,65 is the winter/cold quantity, 0,45 is for summer/quantity--all 4 should be w/in 0,3.
Also, make sure he screened check valve (on the bottom of the carb body) is clean including the 2 side jets too.

Dick

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Martin Benade
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Re: Solex Expert Level Question

#20 Post by Martin Benade »

Swapping injector nozzle position didn’t move the problem so whatever is wrong would be upstream of the brand new injectors.
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Dave Erickson
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Re: Solex Expert Level Question

#21 Post by Dave Erickson »

Check the other parts of the accelerator pump circuit. e.g. is the bleeder hole present and clear of crud in both carbs' check valves? Also check it with a number drill to make sure it is the same size in each check valve.

download/file.php?id=50034&mode=view

You might also want to review this thread about the accelerator pump circuit: viewtopic.php?p=277129#p277129

Rich Goold
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Re: Solex Expert Level Question

#22 Post by Rich Goold »

Martin wrote:

“ a pair of bosses on the side of the pump diagram housing with tiny metering orifices en route to the nozzles? Maybe one is too big, and could be soldered and shrunk a tiny bit. That would shift some flow away from that side and over to the other nozzle.”

This is a great theory. I was not aware of the bosses or metering orifices. Too much fuel is going to #4 and this could explain it.
Also since I am getting TOO MUCH fuel it can’t be any type of blockage or restriction problem. Maybe somebody enlarged one of the orifices in the past 60 years, who knows. I will try to locate the orifices and try to take some measurements

Thanks Martin !

Rich Goold
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Re: Solex Expert Level Question

#23 Post by Rich Goold »

Dave, thanks for referencing the threads below. My previous searches didn’t bring them up. EXCELLENT! Great write up and great pics. Must read for anybody working on the accelerator pump circuit

download/file.php?id=50034&mode=view

You might also want to review this thread about the accelerator pump circuit: viewtopic.php?p=277129#p277129
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Dave Erickson
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Re: Solex Expert Level Question

#24 Post by Dave Erickson »

Rich, glad you found it useful.

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