i have a 74 super beetle. it started running rough a two weeks ago. i checked the carb, spark plug wires, points, timing,spark plugs. everthing is where its suppose to be. the last thing i can think of o do is to do an ol change. i noticed two weeks agowhen i was replacing my air fliter and puting on a oil breather. that there was some gunky in my oil breather line to the air fliter and in the oil filler. could that be the problem that im having. cause i cleaned that stuff out but thought nothing more of it til now. and i live up in wisconsin and my bug has run good every winter til now. i use 5w30 oil. please let me know what you think could be a promblem that i havent checked or might not have thought of. thanks alot.
Bryan

 

The gunk stuff in the breather line, is a mayonaise and
mustard looking foam, It's caused by moisture inside the
engine block, short trips will cause it, long trips where the
engine gets warm enough to evaporate all the moisture
will make it go away, It does not cause a problem at all
most air cooled engines will do this.
Have you adjusted the valves? some will get loose and
some will get tight and cause erractic engine running.

 

Question... why are you using 5w 30 engine oil in a air
cooled engine? I know it gets cold where you are, but
that engine wasn't designed to use that thin oil.
5w 30 is 5 voscosity oil. and is suppose to be as good
as 30w under severe conditions. Yeah.. if frogs had
wings they wouldn't bump their but when they jumped.

 

ok, i checked the valves. they were all fine. and it snowed here after i got it fixed so i couldnt exactly tell if its fixed.and the oil is what ive always just used that. but i might try 10w 30 and see if that fixes it. thanks for your help and if theirs any thing else you can think of let me know thanks alot.
Bryan

 

If the valves were okay, then it will still run the same.
Some times the condenser will get goofy in the dist and
cause the points to act up if you still have that type dist.
changing to 10w-30 wont repair it either, but it will keep
the crank shaft from going bad. The bug air cooled engine
was designed to use straight oil like 20w in cold weather
and 30w in hot weather. and 40w in ex hot like Texas. It
could be that you may have to use 10w-30, but believe
me 5w-20 or 30 doesn't have enough oil cushion to
protect the crank shaft. It's possible in the coldest part
of the year where you are 5w- 20 might work, but in the
warmer days it's too thin.

 

yeah it was the values and the dist cap. but it was also the intake manifold. its freezing cause the heat exchange tubes are blocked, so i have to replace them.