I've got a hydrolifter EA81 longblock that was not showing any compression on #1 cylinder. Leak-down test showed huge leak past the intake valve.

Popped valve cover off to check that it's not stuck valves. No stuck valves, but signs of monkeywrenching on #1 tappet adjusters. Hmmmm.

Pop head off; the valves had kissed the piston tops. Damn. Most noticeably on #1 Intake. Less on #1 Exhaust. #3 piston top shows a kiss, as well. Double damn.

Removed #1 Intake valve and roll the stem on a piece of glass. Yep. Bent. There's a ding in the valve stem. ??? More monkey action.

Headgaskets were Felpro's, so the heads have been off before. Maybe the cases were split and the cam didn't get timed correctly. Nope, got a centerpunch mark visible through the chamfered flywheel bolt hole when it's at 12 o'clock. Hmmm.

 

Is it possible that upon re-assembly, said monkey with wrench fiddled with the DON'T ADJUST tappets, turned the motor over and bent the valves? Can that happen if the adjusters are screwed in all the way and left there? I know that's the second step in adjusting the DON'T ADJUST tappets. First step is put the piston somewhere in the compression stroke towards TDC, if not TDC. Then the screws are backed out to zero lash plus another turn or so.

 

Nate

Edited February 2, 201511 yr by Nate E.

I think it would be very possible if they turned the adjusters all the way in and cranked the motor over that the valve did not fully close and the piston kissed the valve.  

Ive bent the pushrods on an EA81(every single one mind you) by entering a mudhole at 8000 RPM without a snorkel....Its really difficult to bend a valve when the pushrods are aluminum,but stranger things have happened.

Edited February 4, 201511 yr by Uberoo

I've got a hydrolifter EA81 longblock that was not showing any compression on #1 cylinder. Leak-down test showed huge leak past the intake valve.

Popped valve cover off to check that it's not stuck valves. No stuck valves, but signs of monkeywrenching on #1 tappet adjusters. Hmmmm.

Pop head off; the valves had kissed the piston tops. Damn. Most noticeably on #1 Intake. Less on #1 Exhaust. #3 piston top shows a kiss, as well. Double damn.

Removed #1 Intake valve and roll the stem on a piece of glass. Yep. Bent. There's a ding in the valve stem. ??? More monkey action.

Headgaskets were Felpro's, so the heads have been off before. Maybe the cases were split and the cam didn't get timed correctly. Nope, got a centerpunch mark visible through the chamfered flywheel bolt hole when it's at 12 o'clock. Hmmm.

 

Is it possible that upon re-assembly, said monkey with wrench fiddled with the DON'T ADJUST tappets, turned the motor over and bent the valves? Can that happen if the adjusters are screwed in all the way and left there? I know that's the second step in adjusting the DON'T ADJUST tappets. First step is put the piston somewhere in the compression stroke towards TDC, if not TDC. Then the screws are backed out to zero lash plus another turn or so.

 

Nate

 

Darn monkeys should stick to Shakespeare and their typewriters.

Ive bent the pushrods on an EA81(every single one mind you) by entering a mudhole at 8000 RPM without a snorkel....Its really difficult to bend a valve when the pushrods are aluminum,but stranger things have happened.

Push rods on a Hydro EA81 are steel, not aluminum...

There were a light silver color,lightweight,and non magnetic.If thats not aluminum I don't know what is.