sudden loss of power/bogging/surging???

[xboxrox]

Can valve stem oil seals be replaced without taking off the head..? <--- assuming the compression test is a PASS no need pull head, right? What a big job that would be, best of luck to you 'n your truck bentley james

[royster]

Can valve stem oil seals be replaced without taking off the head..?

Absolutely. I've done it. You DO have to remove the valve train. There's a trick of taking out the spark plug, and moving the piston almost TDC...then you stuff rope into the cylinder. Once that's done, you crank the motor so that piston is snug up to the top. The rope holds the valves in place while you remove springs and keepers.

[claych]

Absolutely. I've done it. You DO have to remove the valve train. There's a trick of taking out the spark plug, and moving the piston almost TDC...then you stuff rope into the cylinder. Once that's done, you crank the motor so that piston is snug up to the top. The rope holds the valves in place while you remove springs and keepers.

^^^
Lol in my case I realized 5 'shop rags' could be 'stuffed' into an 18mm plug bore ( oil as the lubricant)

Humble Apologies Sir.