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6

69tr

Jedi Trainee
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first, I posted before about the random misfire. I took the Pertronix module out and re-installed it. That seemed to help. I might have been a bad ground????

The car still idles a little rough. A local mechanic said it sounded like the carburetors. He tried adjusting the only adjustment on the carbs. I told him that that was not the air/fuel mixture. The adjustment didn't help or hurt. When we were revving the engine a little to listen for anything wrong the engine seemed to stall like it was starving for fuel. I brought it home and left it sitting while I did some chores and when I started it again it ran fine. I did balance the carbs while I was at it.

While at idle I lifted the pistons on each carb. When I did this to the rear carb it stalled the engine. When I did it to the front carb the rpm's dropped a little. This tells me that the mixture is lean. The only problem is that the Stromberg 175's don't have a mixture adjustment. Does this mean that I am going to have to buy new carberators? I did rebuild the carbs before I got the car back on the road.

Next question. Can the lever shocks be effectively? Where can I find kits to do this?

Last question. My car had the tube shock conversion when I bought it but the ride was way to hard. Almost like not having any suspension at all. What shock do you guys with the conversion use?

Thanks, Pete
 
Mixture should be a little bit lean, on an emissions engine, but not so lean that lifing the piston a bit (no more than 1/4") stalls the engine. I'd look for air leaks around the rear carb, like maybe the throttle bypass valve diaphragm or the temperature compensator being stuck open. Could also be the fuel level being way low.

If the takeoff for the brake booster is near the rear carb, it might also be a leaking booster.

It is possible to modify the early carbs (only 69 didn't have an adjustment) for a mixture adjustment, but it might be easier to find a pair of the later pistons and install those.

Lever shocks can be rebuilt, but it takes special tools, etc. Not something to tackle at home, but there are services you can send them off to. Be sure to check the oil level first, though, as frequently they are just low on oil.
 
You're right that the carbs that came on the 69 did not have adjustable needles to change the fuel/air mixture.
There are some things that you can try though.
You can increase the the level of fuel in the float chamber first. Normally the level is between .625 and .627 inch. Since the carb is upside down when you make this measurement/ adjustment, you'll want the measurement to be .625 or less. For example; but unlike this picture you have to touch the bottom of the float for an accurate measurement.
floatheight.jpg

You can also see of the needle is seated as high as possible in the air valve to enrichen the mixture.
The next suggestions are strictly "experimental". Tap the jet down a bit. Bore the jet out. Polish the needle down at the shank.
 
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