Engine misfire (non-Marauder related)

[Blackened300a]

My uncle has a 1965 Olds 442 with a olds 400ci engine. He was driving home yesterday and while sitting in traffic, the engine started hesitiating and picked up a misfire.
Today we went through it and found it to be cyl #1. Now heres where we are baffled. We went ahead and did all the basic repairs and checks. We installed new plugs, new wires, new cap, new rotor, pulled the valve cover and checked the rockers which were fine, and did a compression test which was also fine. We have spark through the wire and the plug, it also starts up and runs fine on 7 cylinders so timing and bad gas issues are off the list of reasons.
We are out of ideas and we dont really want to pull the heads off just yet in case there is something we may have over looked. I know about valve guides that slide in the assembly and cause a blow by but it didnt show up on the compression test. I also know about burnt valves and that also didnt show up on the test either. The engine also doesnt thump through the carb or thump through the exhaust so Im kinda leaning toward it to be something other then a valve.

Any ideas what this may be?? :confused:

[Richy04]

Oops, read it too fast.. If you compression test is good, check the intake for leaks, chances are the manifold gasket is bad leading to the #1 cylinder if all of the electronics check out.

[rayjay]

Just a thought Paul, is it getting fuel to that cylinder? Did you try swapping the wires/plug to another cylinder to see if the problem moved? My Dad was a tech for 50 years and used to tell me all the time about new parts that were no good out of the box.

[Blackened300a]

Oops, read it too fast.. If you compression test is good, check the intake for leaks, chances are the manifold gasket is bad leading to the #1 cylinder if all of the electronics check out.

Gasket is good


Just a thought Paul, is it getting fuel to that cylinder? Did you try swapping the wires/plug to another cylinder to see if the problem moved? My Dad was a tech for 50 years and used to tell me all the time about new parts that were no good out of the box.

All the wires are good. With some more research we reved it and had it pop out the intake a bit so we are looking at a sticking intake valve. We put some marvel mystery oil in and hope we can free it up. It has a almost stock cam in it so there is very little lift and combine that with over a year sitting in a garage. The sticking valve seems to be the issue.
Right now its running on all 8 cylinders but it will miss when reved.

[RoyLPita]

Plugs do not last any more than 10k on carbeurated vehicles with points ignition.