"Float Adjust" for Solex H40 ESI's?

Also check throttle plate shafts for leaks and end play.

@JB356SR posted:

Also check throttle plate shafts for leaks and end play.

You bet and thanks. Yeah when I had them apart I wiggled the shafts and there was no play at all. (PS- I'm thinking just go to Webers...)

Whenever messing with carburetors, 1st things that should be done is make sure valves are set properly and ignition is in good working order.  Don't assume- check, because you'll be chasing your tail if one of those other things isn't right.  Is the popping out the exhaust (rich) or carbs (lean)?  I'm guessing that the vibration is from the engine idling on only 2 cylinders- this is typical of dual 1 barrels and the more camshaft duration there is the worse it will be.  I'm told (by someone who's info I trust) that if you take the middle wall out of the manifolds down to about ¾" above the head gasket surface the engine will idle on all 4 cylinders like it has Webers or Dellortos.  I will admit never having the opportunity to try it myself.                                                           Hope this helps.  Al               

@ALB posted:

Whenever messing with carburetors, 1st things that should be done is make sure valves are set properly and ignition is in good working order.  Don't assume- check, because you'll be chasing your tail if one of those other things isn't right.  Is the popping out the exhaust (rich) or carbs (lean)?  I'm guessing that the vibration is from the engine idling on only 2 cylinders- this is typical of dual 1 barrels and the more camshaft duration there is the worse it will be.  I'm told (by someone who's info I trust) that if you take the middle wall out of the manifolds down to about ¾" above the head gasket surface the engine will idle on all 4 cylinders like it has Webers or Dellortos.  I will admit never having the opportunity to try it myself.                                                           Hope this helps.  Al               

Yes I used to run SU's in my SCCA G-Prod Datsun Roadster so messed around with carbs for years. Modified internals with reducing mass of all components that would otherwise not maximize mixture. It worked. That was fun...

Ignition is fine and valves will be done today. My gut says it will not change anything.

Until I advanced it to about 30-32 and tweeked idle mixture a bit, it was popping out of the carbs. Now, it improved greatly to an occasional one out of exhaust. I  will run it again today after valves and see.

Interesting input on the middle wall thing. Thanks Al.

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@LarryGK posted:

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...Ignition is fine...

...Until I advanced it to about 30-32 and tweeked idle mixture a bit, it was popping out of the carbs. Now, it improved greatly to an occasional one out of exhaust....

So, changing the timing helped?

Did you use a timing light to do that?

Reason I ask is that distributors now seem to cause a lot more problems than they used to because many of them are cheaply made copies of the Olde World originals and the mechanical advance bits lack the precision to deliver consistent spark.

Playing with the timing light a little can show you how consistent the spark is. Just watch the timing mark as you slowly increase revs from idle up to 3500 or so. That mark should stay rock solid and move smoothly as you progress.

Mine didn't. The timing mark actually disappeared for quite a bit of that range until it settled down again at max advance. That inconsistent spark (spark 'scatter') made the engine miss just off idle and sounded for all the world like bad jetting, dirt in the carbs, and lack of synch.

A better distributor magically cleaned up all of my 'carb' problems.

The timing light test is one of the easiest things to try before you start ripping things apart and ripping out your hair. Do the easy things first.

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BAM! That^^^

95% of all carburetor problems are ignition problems. It used to be 90%, but has been upgraded due to crap ignition components.

^^^Very good point, @Sacto Mitch!^^^

@DannyP posted:

BAM! That^^^

95% of all carburetor problems are ignition problems. It used to be 90%, but has been upgraded due to crap ignition components.

I forgot that little tidbit in my original post above

@DannyP posted:

95% of all carburetor problems are ignition problems. It used to be 90%, but has been upgraded due to crap ignition components.

95% may be low.

The 009 was never all that great, and the 009 copies are garbage.

@Sacto Mitch posted:

.

So, changing the timing helped?

Did you use a timing light to do that?

Reason I ask is that distributors now seem to cause a lot more problems than they used to because many of them are cheaply made copies of the Olde World originals and the mechanical advance bits lack the precision to deliver consistent spark.

Playing with the timing light a little can show you how consistent the spark is. Just watch the timing mark as you slowly increase revs from idle up to 3500 or so. That mark should stay rock solid and move smoothly as you progress.

Mine didn't. The timing mark actually disappeared for quite a bit of that range until it settled down again at max advance. That inconsistent spark (spark 'scatter') made the engine miss just off idle and sounded for all the world like bad jetting, dirt in the carbs, and lack of synch.

A better distributor magically cleaned up all of my 'carb' problems.

The timing light test is one of the easiest things to try before you start ripping things apart and ripping out your hair. Do the easy things first.

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Thanks for the comments and questions. I always use good a timing light. My dist is a Bosch 009 and max advance stayed steady up past 3k rpm, yes.

Back at it Monday to go further now that valves are adjusted (2 exhaust and 1 intake were over spec) . Will check timing once again.

Short of that everything else I know of has been adjusted and done.

Encouraged to hear your stories with these exact carbs and the issues you all ran into along the way.