Left 2 cylinders running hot

I would check the carbs to see if there is any blockage in the pilot/main jets, or in the fuel circuits to the carb throat.

I took carbs 3&4 apart and sprayed them down throroughly.

After that, cylinder 4 started working again!! Cylinder 3 is still not igniting. Must be some serious gunk in there. Gonna spray that one down again.

I can't get carb 3 to clear up and start running. I sprayed all the passages twice with carb cleaner and compressed air but it's still not doing the trick. Getting so anxious about this cause I'm so close!!

Okay so I've taken the carbs off and sprayed carb #3 6 times now and it still isn't running.

Anyone have any idea what to do?

I figure I would tell you about cylinder balance testing. It won't really help your cylinder 3 but you'll figure that one out soon.

A cylinder balance test is done with the engine running.
While looking at the tach you pull a spark plug wire and note the rpm drop.
If the cylinder is dead, the rpm drop will be less than a cylinder that is working.
People will usually use a test light connected to ground to take the spark from the pulled spark plug wire so they don't get shocked.

Just another diagnostic method.

I guess as far as carb #3. I would verify that #3 is pulling the same vacuum as the other carbs.
If you pull the filters, you should also verify slide movement. You could additionally bring the rpm's up to see if your needle circuit on #3 starts to flow.
Your bowl vent for #3 could also be clogged

You could put it in an ultrasonic tank.

Have you checked the air vents on the intake side of the carb?

The problem with pulling a plug while running is that now you are asking the spark to jump a huge gap. That is extremely stressful on the coil and igniter. Also, if you don't ground that lead after pulling it, you may lose spark on the other cylinder as well which will be misleading.

loudhvx wrote: The problem with pulling a plug while running is that now you are asking the spark to jump a huge gap. That is extremely stressful on the coil and igniter. Also, if you don't ground that lead after pulling it, you may lose spark on the other cylinder as well which will be misleading.

Oh don't worry, I had the plug grounded when I checked for spark.

However, I was able to unclog the carb! It's now firing on all cylinders and rides like a dream now.
I had to get a different brand of carb cleaner that had a stronger stream and was able to clear it out. Not sure which passage was be blocked, but that don't matter!

Whoever suggested "maybe the right 2 cylinders are cold," thank you!