68 super bee one cylinder running hot

[Lukas_z]

I have a 1968 383 4 speed super bee with one cylinder that is running hot. I start it up and the exhaust starts to pop almost right away and the second second down pipe on the passenger side of the header starts to get way hotter than the rest. If it runs too long it starts to glow red. What do you guys think is the issue. i have an edelbrock carb on it. I think it's a 650(not 100% sure). I've been looking around and it seems that it's one of two issues. An intake leak or blockage. Am I in the ball park here? any help would be great.

Issue 2 I had coolant leaking on the header, I did not realize that the manifold bolts go directly into the cooling passages, so I put thread sealant on all of the bolts and the leak went away, however it seems like the upper radiator hose is building up pressure and is staying cold(as if there was no coolant in it just air). Am I doing something wrong here too?

This engine was freshly rebuilt so could it be an engine issue or is it an installation issue on my part.

Thanks again for the help.

 

[Moparsmitty]

A few ideas. First check the basic stuff. Make sure the plug wires are run to the correct cylinders in the proper firing order and check the ignition timing. It may be an intake gasket vacuum leak causing that cylinder to run too lean and run hot.
Worse case what may be happening since it's a new rebuild is that the exhaust valve in that cylinder isn't closing all the way and the fuel is burning in the header pipe. If you have adjustable rocker arms, check the adjustment on that cylinder. If you have stock rockers you might have to go to shorter pushrods but check everything else before you tear into the valvetrain. Good luck.

 

[62 Dart Convertible]

I'd agree with Moparsmitty above. Check the basics of ignition first, timing, firing order. If all OK, I'd suspect exhaust valve not closing properly either from a valve train issue or a valve/guide seizure.

 

[Lukas_z]

Thanks for the input guys. It was a simple fix after all, I ended up having the #3 & #4 cylinders hooked up backwards. I made my own wires for it since the "factory" replacement fit like crap and when I installed them I must have crossed those two.

 

[62 Dart Convertible]

Glad it was something so simple!