A recent compression test produced these results:
1 - 65 psi, 2 - 35 psi, 3 - 45 psi, and 4 - 45 psi.
How can the high number on cylinder 1 be explained with a stock engine and head?
Worn out.cam shaft.
You need to go further. Give each cyl. a shot of oil just before testing and re-take the cylinders. There may be a difference in the 2-3 & 4 readings. If it goes up it's usually rings. No change possibly indicates leaking valves. I've seen 1 engine with 65 Lbs across the board but it did have some work done. It could be a cam as suggested but you really should do the oil thing first.
Carbon build up in no.1?
Also, be sure the throttle is wide open and the choke is also fully open.
What kind of head and pistons do you have? 65 seems kind of high, but if it is correct, the others are too low. 35 seems low. I would suggest that you check again with a different compression gauge before you pull everything apart. Your gauge might have some problems.
If you get the same compression, tear things down and inspect.
Screw the plugs back in part way, start the engine & run it a minute, shut it down and recheck.
I have been beaten by that one before.
Maybe they are al 65 but when you broke the spark plugs loose some fine carbon broke loose and got under 2 or three of the valves.
It happens, but usually only one valve traps some carbon under it as it is going out the exhaust port.
dont be to quick to take it apart run it a while test again and try a diff. gauge is it running?
Another thought. That 65 pounder is bothering me. Especially when compaired to the others. How well do you know this car/engine? Is it possible some half a**ed job was done where just one piston & rings were replaced and the other 3 are original?
An excellent possibility!
A little more research will be done, before the head is removed.
This vehicle was recently purchased, so anything is possible.
All the tar was leaking out of the #3 coil and the wires could have been totally crossed to put #1 coil on the drivers side and make that coil run cylinder #1.
The worn out cam shaft is opening and closing the valve late / early respectively. Thus the cylinder pressure is higher.
James,for the #3 coil boiling all the tar out you have a short in the wire to the timer and the coil keep buzzing till it died.
Have seen this last sunday in France, not easy to clean out.
Andre' gebruikte hij 12 volt of liep de motor op magneet ??
Weet ik niet Toon maar volgens zijn uitleg is het s'nachts gebeurd. Het contact was nog al los en kon zonder weerstand van links naar rechts worden bewogen. Het contact zou weleens de ganse nacht hebben opgestaan.
Toon asked me if the car was running on 12V battery or Magneto?
I don't know Toon. As the driver told It happened over night. His contact switch was loose and can be moved from left to right without any resistant.
It could be contact was on the all night.