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TR2/3/3A Lean carb mixture again....

karls59tr

Obi Wan
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Would a carb mixture on the lean side cause a higher idle? Would a leaner mixture create a situation where the car would be harder to start even with the choke knob pulled out all the way? (linkage is set up correctly) Car wants to idle around 1200+ rpm and will die out if I drop it to 800. The plugs do not look white but relatively clean but not really a light brown. I do have a mild street cam so I suspect that a bit higher idle might be suspected because of that. Any thoughts? Karl
 
Could be... Have you checked for a vacuum leak? May be an issue.
 
Here's some places:
Anything attached to the into the intake manifold, including the carbs and cylinder head
Any vacuum hoses attached to the carbs and distributor
Carbs' throttle shafts where they enter the body of the carbs
 
+1...sounds like an air leak. Take a can of carb cleaner, ether, brake cleaner, etc. and spray it around the throttle shafts, carb bases, manifold to head gasket. When the engine revs higher you found your leak.
 
Hi, If do not find a vacuum leak, check the mechanical advance in the distributer. Pop off the cap and twist the rotor. Let it go, it should snap back to the original position. If not, it likely has broken springs.

Good luck, Roy
 
Your plugs should have a slight brown dusting to them if the mixture is set correctly. If they are clean and "glazed" or a bit shiny, then definitely lean and the mixture should be adjusted by a couple of flats to be slightly richer. I use the Colortune sparkplug for setting the air/fuel mixture and find it works well.
 
Your plugs should have a slight brown dusting to them if the mixture is set correctly. If they are clean and "glazed" or a bit shiny, then definitely lean and the mixture should be adjusted by a couple of flats to be slightly richer. I use the Colortune sparkplug for setting the air/fuel mixture and find it works well.
The plugs are clean and a bit shiny. I'm going to richen the mixture a couple of flats.(y)(y)
 
Well it's the dead of winter here and i do not have a heated garage so I'm going to have to wait until May to play with the carbs but thanks for your interest. I will keep you posted.:smile: Karl
 
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