I've used something like these in the past (been since the 70's though). I had a collapsed lifter that then hammered the pushrod through the rocker cup:




George

 

Okay sounds good thanks guys, I'm gonna pull the valve cover off soon here just waiting to pull it in my garage - it's raining today. I think I will figure something out with some cardboard and paper towels to try and catch all the oil, I'm not too worried about things getting too hot because my engine will be cold when I start it and I probably won't have it running for too long. Les, when you talk about compressing the internal plunger in the lifter when the valve is closed, how do I do that? Just push down on the top of the pushrod?

 

top of the rocker above the pushrod.

 

Thanks Les, so I got all the valve cover bolts off and realized there was no way it was coming off without moving the PS bracket, and it didn't, I don't know why the manual doesn't mention this or anything so I took the ac compressor off and moved the bracket. About half of the rockers wiggle back and forth a little bit, is this normal? The rest looks ok on first look. I will put it all back together now so I can start it up.

 

Ok guys I really thought I was going to find something here... But everything seems fine to me, the valve seems to open just as much as the intake valve right next to it, WTH? And it also has no play when I press on the top of the rocker on the pushrod, back together it goes I guess...

 

Hold on, unless you have to drive it please look some more. If you did the test correctly and I believe that you did, there is something amiss with #1 cylinder. How about pulling the rockers and inspecting the push rods rolling them for straightness? Can you get a ruler next to the valvespring and measure/compare the movement? Its going to be something with the valvetrain causing the snap and running values observed. Its a smoking gun!

Also in the video. Is the spacing between the first coil down at top of valvespring different from the intake valvespring? This with both valves closed? Could be optical illusion? To me first coil down looks closer to retainer on exhaust valve.

 

Thanks Les, I just need it back together by the end of tonight so I can go to work tomorrow, I just realized I'm not going to be able to use the valve cover gasket as I thought, I can't get it to sit right back in the valve cover so I'm off to the parts store to get a new one before they close. When I get back I will look at it some more before putting it together. What should I look for when I take the rockers off? I will try and get a ruler in there while it's running later and get a video. I was really thinking I was going to find my problem today with this because I think it must be something in the valvetrain too, but I get in here and it looks fine! Let me know if you think of anything else I should look at.

 

just check pushrods for straightness and wear on ends. Rockers for wear in pushrod cup, cracks in metal and slop in needle bearings. You could also swap rockers/pushrods with #5 and see if problem moves. If nothing found there start thinking about a bad cam or lifter - but would be deeper checking with intake off. If you swapped #6 exhaust lifter or rocker into #1, those parts could be damaged from bending that pushrod and whacking that piston.

 

Thanks Les, I pulled the rocker off the #1 exhaust and it looks good, same with the pushrod, it's straight. I'll get a ruler out in a minute to check on that. It's an illusion in the video Les you just have to remember it was shot a bit crooked, I was looking at that too LOL. It's just so weird how I can't find anything wrong here!! I think if I take the intake off (possibly next weekend) I will just replace all the lifters either way, at that time I will be able to inspect the camshaft also but I remember looking at it when I had the engine out and I remember it looked fine. I have narrowed it down to 5 parts that could be causing this, camshaft, lifter, pushrod, rocker, and valve, and 2 of these parts are brand new (valve and pushrod) and I have the pushrod and rocker out right now looking at them and they look fine. I'm thinking it must be the lifter, I just wish it would be more apparent that's what's causing the problem.

 

Might want to repeat the snap test on #1 before replacing any more parts. Just to make sure. Those lifters are pretty pricey for a full set. I would really hate to see you continue to be disappointed.