Doug McKillip

ok- a little more info. When I spray carb cleaner into the PS barrel - the car revs a little, smoothes out, and purrs along for about 3 seconds. At that moment, it runs like I thing it should. I do drive it! When I hit the gas it revs up, sounds like monster heavy metal, and would spin every bit of rubber of the new tires if I kept the hammer down. Much of what is being suggested is beyond me (and my somewhat limited tools) but this is a one man show, so the cotton ball was, I thought, pretty smart when I am spinning the engine using one hand on the fan and torking down on the belt with my other hand. Based on my very scientific cotton ball test, I think I have 1 at 1. I will kepp working...

Doug McKillip

I put the infrared therm on the EM. All were over 300, except number 4 - which o I only got to register around 180 when the engine was idling and hot. Still working...

Gun Jam

if it runs better when you spray carb cleaner down it or under full power then we are back to where we started....at the carb.

It seems more and more likely that you are dealing with a degraded idle circuit. The carbs are not difficult to service or clean but there are many small passages and you will need to remove the carb from the engine and break it down on a clean work bench and go through all the jets and ports. Typically a blockage is not hard to spot.

-Gun

barnett468

your cotton ***** is only a good idea if they were too big to get sucked into the cylinder as the piston went through its intake stroke, lol.


What do you mean by "PS barrel"?

If this means driver side then what happens when you spray it in the drivers side?

So, your car runs fine and hauls a_s?

Your only problem now is rough idle and 1 cold cylinder?

It sounds like you did not remove the metering block/venturis as i suggested because you said you you only removed the mix screw and sprayed carb cleaner in there. If this is the case, I would still remove the block and clean it in the manner I suggested. This will NOT fix your 1 possibly dead cyl but it might help it idle better. I have had to do this dozens of times on stock carbs.

300 deg might be a bit low but not a concern.

I would set the idle to around 2000 rpm then wait 2 minutes and check it again this might provide a wider range in temps seen.

Take it around 6" - 8" away. Air from the fan can lower the temp you see if you are too far away.

If you get less than 2" away it might kill your test light. I speak from experience.

Shoot the beam on the ex manifold just 1/2" down from the head. If you shoot it too far down, the heat from the other ports will affect the reading.

If your results are similar then take the plug wire off the cyl that is cold and exchange it for one on another cyl.

If the new cyl is now cold your plug wire is bad. If the same cyl is cold then exchange the spark plug.

If the same cyl is cold then it IS firing, however, you likely have very low compression in it. This is the reason I asked you to do a compression test.

If you have a brand new engine and you pull the wires one at a time the engine will NOT change rpm's by the same amount for each. this is simply a phenomenon caused by the engines design, therefore, pulling plug wires is not an accurate test. You thought you had 4 bad cylinders but by the temp gauge you only have one. One is all it takes to make an engine run horribly.


Did you replace the power valve when you cleaned the carb, it comes in the carb kit? If it's leaking it will cause huge problems.