Setting solex float levels

[Mark Todorovich]

My carbs were redone in another city ,not so easy to just drop by. The symptoms are a dramatic drop,in gas mileage from before the rebuild. It was suggested I reset the float level. That left one is right on using the nongauge method in the article in resources. Removed the nut from weephole ,adjusted until gas came from screw on outside ,then dialed back just enough to stop the weeping.

The right one using the same method , I can't get the level high enough to have the gas seep out. It was suggested to check the float ,it wasn't stuck, it didn't have gas in it. I see how the adjustor moves the plate with triangle in and out moving higher the pivot for the float. On the phone to the Major carb rebuilders they mentioned shimming out the float valve. I don't get it , wouldn't that make the level lower. Carb is in the car and apart , ideas are welcome.
Thanks
Mark

[Doug McDonnell]

Slowly pour gas in the float bowl and see if float rises and you get gas out the hole. If so then I suspect that gas is not getting to that carb. Measure your pump pressure. I read about a bug in the line behind Shroud once. Maybe a Maestro story? Most rebuilders set float level as part of rebuild.

[David Jones]

Mark. I had a similar problem recently twice. That is a low fuel level, not the low gas mileage which I would have associated with a lack of power not a carb fuel level problem. How is/was the car running anyway? Have you noticed a lack of power?
First time I had the problem the adjuster arms were too tight on the float fulcrum brass inserts and did not allow the float to fall as the float bowl emptied. It was somewhat intermittent so took a while to find. Second time was a week ago when the car died right after filling with gas and leaving the gas station. Sat for a minute and fired it back up then drove away and 200 yards later it lost power so I pulled over in a parking lot and did a quick check of everything I could think of while the engine was still running. I ran the revs up and down a few times and it seemed OK so drove 10 miles home with no problems. I ate lunch then went to put the car away in the garage which is about a 100 yards away and it did not feel right so I left it idling albeit roughly and did the straw test by dropping a drinking straw down the vent tube. As I suspected there was no fuel. I took the carb off and set it up on the bench and with 6 feet of fuel line hooked up and the end hung 6 feet in the air I filled the line and checked the level. Absolutely perfect level. Took the top off and checked the float valve and everything else but found nothing wrong. Re-assembled carb and refitted it and it seems OK so far. From all that I deduce I may have had a small amount of debris in the float valve which disappeared in the diagnostic stages or the float valve is defective which means that it will get changed out if it happens again.
As to adding a shim under the float valve you are correct that will make the situation worse by shutting off the fuel flow even earlier and lowering the float level. If you do not have spare parts may I suggest you swap carb covers and see if the problem swaps sides that way you will know if it is the float mechanism or the float valve and it's position in the carb cover.

[Richard Shilling]

Check the carb top cover for the two springs that hold down the float pivot pin.

[Mike Horton]

Check the jet numbers, and if you have a jet gauge available to you, check them, to be what they are marked. For my 40 PII, on 10% ethanol, up at 3300' elevation, I have to run 57.5 idle fuel jets, and 127.5 mains, to keep my oil temp to normal, and get my fuel mileage back. Be sure the 4 flush jets in the top, are in the correct holes... a few other things found in the past,

[Mark Todorovich]

specking jets, that is probably my next question, St. Louis is about altitude 450. What's is the suggested jets?

[David Jones]

Go with the original jets Mark, they should work fine. If you feel the engine is getting hotter than it should you could bump up the mains and idles to the next size up. The ethanol in gas has less BTU's than straight gas so the car could run a little leaner than stock but it has been a long time since we ran leaded gas without ethanol so it could be anyone's guess what jets would be correct now unless you put the engine on a dyno and tuned it properly. I run stock jets or close too and I am closer to 1000 ft.

[Dave Erickson]

Mark, I assume you have solid shaft 40PII's, since your photo shows solid shaft butterflies. If so, your main jet should be 117.5-120. Split and solid shaft 40PII's have different idle circuits; on split shaft 40PII's the main jet supplies both the idle circuit and the main jet circuit, so it needs to be larger.

-Dave