Originally Posted By: OceanRuns
Originally Posted By: CT8
The older Ford engines had those gaskets. They are needed so dirty air will not get sucked into the engine. PCV valve.
The way this particular cap is set up is the cap itself has a rubber hose going directly to the intake. It seems positive pressure is being vented out through the cap itself.
So, would the gasket be there to ensure the gases vent through the hose rather than just out to the atmosphere? How would anything be sucked in? Forgive me if I am misunderstanding, just would like to know how it works.
I do intend to replace the gasket if I can find one.
It's unlikely that crankcase pressure will outrun the intake draft, I suppose possible on an old, very worn engine. Well, yes, thinking back, I owned such an engine once, one with significant crankcase pressure, but it had a bad piston. But even if, you might get unfiltered air intake at the missing gasket due to
Bernoulli's principle.
For your own peace of mind, pull the valve cover. Check each rocker arm tension while you're in there.
BTW we had one of these cars in the family. No surprise the engine is still on the road. Lots of surprise on the car. Typical 80's Ford quality, started rusting the moment we got it home. Weird start/idling/emissions problems denied by dealer and finally sorted out by a local independent mechanic. Specialty fasteners everywhere, had to buy Torx (or something like it) just to change the shocks, and a funky socket to change the oil pressure sender. (Still have that socket, never used it since). Why did I have to change the oil pressure sender? We've had Fords in the family since the Model T, never had to replace one before. Something on that Fairmont broke once a year like clockwork. Just Ford 80's quality.