Valve Clearance? Options

[last337]

Can someone explain this to me? I have been fighting with this thing for some time now. I had so many problems for so long with my engine just dying and after pulling my tank and changing fuel lines and filters I am back running again.

Now I am having another issue where I will get my dual carbs tuned just right at operating temp and be running just fine. However, after a while I start to hear backfiring again. The only thing I havent done in a while is set my valve clearances. Actually it has been a long while since I have done that and I am suspicious about it being the culprit.

I understand how if my timing was off or my mixture was off I could hear pinging or backfiring through the exhaust. But I dont know why my valve clearance would do that only as the temp of the engine changes or just seemingly by itself at times.

Can someone explain how proper valve clearance is so critical?

[r_towle]

Get the right ones or they won't line up.

Get 2.0 liter spacers.

So, seeing as you don't have them, there is a phenomenon named hydro lock on carbed cars that can happen when you stop the car.
These motors actually get hotter right after you stop them, as a heat sync.

This can boil the fuel, overflow that fuel into the cylinder, then you cannot turn over the motor because its now filled with enough fluid to hydro lock the piston in place.

Spacers help prevent this so you isolate the carbs from the motor with some plastic....phenolic spacers are the normal thing we all use, cause they can be bought everywhere.


Rich