For reference, is plug #1 at the top or the bottom of the photos???

It's just a bad engine.  Bad rings or cylinders or valve seals/guides.  You've got many miles out of it.  Consider finding a replacement.  Or run hotter plugs in the bad cylinders and hope the plugs stay cleaner.

Thanks for your honest advice. I think its about time to take this engine out of the car. Im running BP5ES plugs in all 6 cylinders and the order of the plugs is 6-5-4-3-2-1. If i close the fuel mixture nut half turn in at the rear carburetor i loose power. 

 

2 hours ago, jalexquijano said:

the order of the plugs is 6-5-4-3-2-1.

Are you sure?  It should be 1-5-3-6-2-4.  Counterclockwise.    Error.

Here's an old CZCC thread with pictures.

 

Edited February 19, 20232 yr by Zed Head

I know the firing order. The picture is taken 6 5 4 3 2 1. Number 4 the problem child. 

In the correct firing order 4 is next to 1 and 2.  There is nothing to argue about.  It's either wrong or right.  The engine will still run with the wrong firing order.  It will just run very poorly.

Oops.

Edited February 19, 20232 yr by Zed Head

He's listing the plug relative to cylinder number for the plugs laying on the fender.

Not firing order

Thanks Patcon.  My mistake.  I saw the word "order" and my brain went to firing order..

#6 doesn't look very good either.

Edited February 19, 20232 yr by Zed Head

I agree with you. I think the engine has some kind of internal flaw.

9 years struggling with this crap and wasting money in inexperienced mechanics

46 minutes ago, jalexquijano said:

9 years struggling with this crap and wasting money in inexperienced mechanics

I know it has been frustrating. Some of the mechanics might have been inexperienced but if it's an internal problem, that's a little hard to diagnose unless the same mechanic works on it every time. After every other possibility is exhausted then it has to be something internal. I believe that is where your at now...unfortunately 😞

15 hours ago, Patcon said:

I agree with you. I think the engine has some kind of internal flaw.

 But, as I recall, the compression was good on all cylinders. Correct me if I'm wrong @jalexquijano.