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TR2/3/3A How does this sound?! [Video]

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HighAltitudeTR3

HighAltitudeTR3

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Hello Friends,
I’ve been working on my turning lately and I can’t quite seem to get it right. Any suggestions?! I have a feeling my distributor is not vacuum advancing. Anyway to test this?

Thanks so much

https://www.youtube.com/watch?v=__2CZaBcNQc
 
Sounds OK, how does it run?

The vacuum advance can be tested several ways. If you have a MITY-Vac, you can attach it to the line, and looking at the points plate, while pumping the tool, see the plate rotate. You can watch the gauge to see how fast it leaks down. -Or- You could use a timing light and when you pull vacuum, see it advance. If you don't have a pump, you could try sucking on that tiny line. I found mine clogged. It is a very small diameter hole in the pipe and very difficult to clear.

-But vacuum advance only occurs when the throttle is just opened and doesn't effect the way the engine runs very much.

The mechanical advance working properly really effects the way the engine performs. Often the springs are worn and are not returning the points plate to the home position. The two springs are different lengths and strengths and create the 'advance curve'.
 
Is it unheard of to remove the vacuum advance on these? The little pipe can’t be moving that much air, I had about 10lbs at full throttle.

I thought about replacing the springs for the mech advance, but I figure I’d only do that if I had a problem.

One of my biggest problems is my plugs are jet black. I know it’s running rich, but I can’t dial down the carbs any more, they are maxed out. Even with the largest needle I could find.
 
Have you driven it? High idle in the garage will almost always be sooty. Get it out on the road and test it. Also check your linkage for binding and return spring on the throttle arm to address that idle. Should be around 800rpm after warming up.
 
Ignition timing, especially if too retarded at idle will soot up spark plugs even with an otherwise good mixture setting as will too "cold" of a spark plug.
 
I had a problem like that once and it was the oil rings. It looked like black carbon but was sticky and not dusty. You do mean you turned the nut all the way up tight against the jet and not out and down? The car would not run if the brass nut was turned up against the jet and jet fully returned against the brass nut. So perhaps your choke is not letting the jet come back home. Can you take your finger and push jet up anymore? Do you need a choke to start the car when cold?
 
If you can’t get the carbs any leaner, then the jet/needle are worn and need replacement. Of course before you condemn them, make sure the choke is fully raising the jet...and look in the carb throat with no air cleaner to make sure you see fuel in the jet, but it is not running down the throat to the motor (That checks the float level).
 
I did not listen to the engine the first time and it sounds good plus the engine looks like you recently rebuilt it? So I doubt if my first idea about the rings or the valve guilds are bumping oil into the chamber. And yeh I do not think you would get a big problem with fouled out plugs without the vacuum advance hooked up. Do you have an electric fuel pump? I thought I saw fuel filter on the firewall. Too much fuel pressure will also cause carbon build up; they need like 2 psi. The problem could be a few things coming together in a nexus creating the carbon and most have been mentioned, like needing new needles and jets and weak plug wires or wrong plugs (try Champion) and poor rated fuel. Usually parts stores will have plugs for tr4 which are the same. Not long ago BPNW had a new distributor for sale for like 125.00 that could make a big difference.

Stay after it you are close.
 
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