recently I took my heads off and replaced the valve stem seals. when I put everything back together I followed the repair books and am reasonably sure I did it correctly. (tighten the rockers till the rod couldn't move up/down or spin then did 3/4 turn more) but now im running it and I have a what sounds like a miss (even thought I put new plugs(properly gapped)/wire/cap/rotor) and heres a interesting fact which makes me think valves, is when I let off the gas theres a faint new noise that I can only describe as the engine brake on a semi, ofc not nearly as loud but can still barely hear it, also im sure I heard for a second very loudly valve chatter, but only for a second.

so now I need to adjust valves while its running and I don't now how, so tips on that? anyone within like a hour drive of royal oak mi that can help?

 

Adjusting the rocker until the pushrod has no up and down movement is fine but it normally should still spin slightly if your fingers are strong enough to turn it. You tighten the rocker until any looseness is taken out of the pushrod. This doesn't mean the pushrod will be tight, it just won't flop around, wiggle etc. Once you've done this, the rocker is at zero lash. The hydraulic lifter requires around 0.030 - 0.060" of preload. From zero lash, you tighten the rocker an additional 1/2 - 3/4 turn to achieve this preload.

After the rocker/lifter is adjusted, the pushrod will still spin slightly when the oil bleeds off from the lifter. This is normal and does not require readjusting.

From the sounds of it, you may have your rockers too tight and they're holding valves open.

 

Yup, compression miss.

 

hmm would make sense. so how do I now when loose is to loose? and I think maybe one or two is tighter then the rest

 

well today was a waste, adjusted them again and still doing it. so eighter something is wrong or I suck that badly at simple instructions >.>

tho... the rods did spin after I adjusted them when I rotated the crank, so I rotated the crank again and adjusted them again, was the 2nd tighten to much?

 

Adjust em with the engine running.

Sure, makes a mess; but, put down plenty of newspaper, then a trip to the car wash takes care of the rest.

 

Yes. If adjusted properly the first time, you DO NOT adjust them again. Hydraulic lifters will feel loose after they've been adjusted. That's how they're designed.

Adjust them all to zero lash and start the engine. They will spray a lot of oil. Adjust each one with the engine running. You should be able to turn the rocker nut 1/2 - 3/4 turns to stop the clattering. Any more than 1 full turn from zero lash and you have some sort of valve train issue.

Instead of backing off all the rockers to zero lash, start the engine with the valve covers off the way you currently have the valves adjusted. Back off a rocker until it starts to clatter then tighten it back up until the clatter stops then go 1/4 turn more and move to the next rocker. Do one side at a time to keep the oil mess to a minimum.

Worst case scenario is that you had them adjusted too tight and a valve made contact with a piston and bent a valve keeping it from fully closing.

 

ok got the valves adjusted, with out a mess eighter. turns out it only sprays oil when revved to about 2k+. runs soooooo much smoother now, seems like a slight miss but that's how it was before, not even sure if its a miss tbh. no bent valves. thanks guys.