[Schurkey]

Originally Posted by JMB36TA

I’m trying to get the fuel and air adjusted on my Q-jet. Judging by the burning eye sensation I’m getting a lean mixture.

Burning-eye exhaust is typically from misfire. Could be lean misfire, could be bad ignition, could be anything that causes misfire.

Originally Posted by steve25

You really don't need a vacuum gauge as you want to set the idle mixture screws for the fastest rpm you can get ( as in lean ) with auto Trans as when you drop it in gear it will go just a tad rich.

I run the engine until it's fully warm. Chock the wheels, engage park brake, put it in gear, and then adjust for highest vacuum. I find a vacuum gauge to be more sensitive than a tachometer.

Originally Posted by gtofreek

You may need to put a small hole in the front butterflies in order to get the butterflies closed enough to not pull fuel from the transition slot.

I have a Q-jet with holes in the primaries, apparently done by Rochester. That said, I'd drill holes in the casting to route some idle air around the throttle blades, rather than drilling the blades themselves if possible. Many Q-jets are drill-able for idle air bypass.

Originally Posted by 455GRIN

Turn the idle down low, and try the mixture screws again

Yup.

[JMB36TA]

Originally Posted by Schurkey

Burning-eye exhaust is typically from misfire. Could be lean misfire, could be bad ignition, could be anything that causes misfire.

I never thought of misfire. I'll have to look into that.

Originally Posted by Schurkey

I have a Q-jet with holes in the primaries, apparently done by Rochester. That said, I'd drill holes in the casting to route some idle air around the throttle blades, rather than drilling the blades themselves if possible. Many Q-jets are drill-able for idle air bypass.

It has idle bypass. Cliff recommended opening it up to .110 which is where it's at now. Not sure where else I would have to drill to add more.

["QUICK-SILVER"]

Originally Posted by JMB36TA

One thing I read was to cover the front opening with your hand to see if the engine races, mine dies.

Originally Posted by Greg Reid

You may know this but just to be clear, you only partially cover the primary side of the air-horn with your hand. Don't choke it out completely. You're just interrupting the air flow a bit to see if it's rich or lean in the idle circuit.

Need to try this again

Like Greg said, don't choke the engine out. Just start restricitng air flow to see if the engine idles up or idles down.

Also might need to check for more vaccum leaks.

This car got the hot idle compensator on back?

Clay

[JMB36TA]

Originally Posted by "QUICK-SILVER"

Need to try this again

Like Greg said, don't choke the engine out. Just start restricitng air flow to see if the engine idles up or idles down.

Also might need to check for more vaccum leaks.

This car got the hot idle compensator on back?

Clay

I choked it out but as I slowly covered it I didn't notice any change in idle until I got close enough for it to die.

I've been checking for vacuum leaks over and over and haven't found anymore. All vacuum lines are new. I haven't checked around the carb since I put it back on Monday night so I'll check that again. But I had this problem before I took it off that night.

Yes it has the hot idle compensator. It's off an Olds so it has this little spring and rod sticking out the back. I sealed around it so there's no leaks according to Cliff's instruction. Maybe I should find a new compensator and cover?

["QUICK-SILVER"]

Was there parts under the cover? The cover holds the compensator in place.
To run without, the holes in the carb body need plugged.

Also need to find out if those are the right mixture screws. I was thinking 69 used the blunt nose mixture screws, where yours appear to be the long tappered nose. Can't say for sure on that but Cliff or some one else might know.

Clay

[JMB36TA]

Originally Posted by "QUICK-SILVER"

Was there parts under the cover? The cover holds the compensator in place.
To run without, the holes in the carb body need plugged.

Also need to find out if those are the right mixture screws. I was thinking 69 used the blunt nose mixture screws, where yours appear to be the long tappered nose. Can't say for sure on that but Cliff or some one else might know.

Clay

Yes the part was under the cover. I'm 99% sure that I put it back in but now that you mention it I'm going to have to check. There would be no reason that I left it out other than I over looked it.

Don't know about the screws but would they really make a difference?

["QUICK-SILVER"]

Originally Posted by JMB36TA

Don't know about the screws but would they really make a difference?

I can't remember when the nose shape changed on the screws.

Pretty sure the long tapper screws would bottom out on the spring before cutting idle fuel off. That's if your base plate is suppose to have the blunt nose mixture screws.

Might try taking a spring off to see if the screw will go in further and kill the engine at idle...???

Even with lots of bypass air, should still be able to cut off idle fuel.

Clay