valve adjustment question

[benzboy]

just doen my first adjustment. wasnt reallty that ba. the cars a 71 911t. question is, im assuming i did everything fine. valves dont tap, but did notice some exhaust smoke. this is my first carb car. only had it for a few weeks, its a project car, so havent been running it too much. back to my question. what happens if i have the valves too tight or to open? what should happen. thanks a lot.

[Tippy]

Worst case, valves hit pistons. If slightly too tight, possibly backfiring and loss of cylinder pressure causing a misfiring cylinder or more.

[CharlesJones]

My understanding is that too loose means a rattley tapping sounds from the engine and loss of power, and too tight means quiet engine but the valve stems will overheat causing the valves to burn out. I am not sure if the exhaust smoke is a sympton of either condition - I have never heard that it is or not.

When you adjusted the valves did you check that the feeler gauge would still slip in and out after tightening the locking nut down?

[DRACO A5OG]

Loose is better than too tight. Wrenches tend to error on too loose then too tight.

Smoke? what color is it?

[benzboy]

yes i did check the clearances to make sure there was a little resistance with
using the feeler gauge. it seems to only have the exhaust smoke on cold start up. after about 5 minutes then it seems to disappear. im just a little worried, since this was my first valve adjustment.

[Trackrash]

My car will smoke occasionally on start up. Usually after it is parked on a slope. Sometimes a big puff for a few seconds. Kind of embarrassing. Probably has nothing to do with a valve adjustment.

I doubt you have anything to worry about as long as it idles and runs smoothly.

[Drisump]

Too tight can actually leave the valves always slightly open therby causing loss of power and overheating of valves. Myself, I always pull up on the rocker after doing the adjustment to sense a minute bit of clearance. As was said earlier too loose is much better than too tight. Cheers

[docrodg]

Oil tends to run from the tank to the pump and collect in the crankcase. If the car is sitting long enough you get a small pool of oil in the cylinders that causes smoke at startup that is blue in color. Should go away pretty quick. If you get it for a little while longer before it disappears I would suspect you have some parts that are worn just enough that they seal up fine once the engine has warmed a little. Wouldn't hurt in that case to run some compression and leakdown tests. Unfortunately these early cars do not have a good method of checking for valve guide wear and seals without tearing them down.