Hydraulic Lifter Valve Adjustment Changed.... uh oh?

[vwlover77]

Last summer, I had to install a lash cap on one my valve stems that looked like this:



I adjusted the hydraulic lifter at that time to 1 3/4 turns, or so I thought. It's been a few thousand miles so I figured I should check the adjustment again just to make sure it was OK.

I carefully began backing off the adjustment screw noting how far I had turned it before the adjuster stopped contacting the valve stem and only made it about 1/4 turn. Uh-oh.....

But wait a minute.... If the valve seat is receding, the valve stem would be protruding out further toward the valve cover, right? The rocker arm would then force the pushrod further into the lifter. So I would have had to turn the adjuster screw more turns than the original setting to back it off, not fewer, right?

I'm thinking maybe the lash cap wasn't fully seated when I adjusted the valve, but now that it is, I lost lifter "pre load" .

So maybe everything is OK inside the head??????

[airkooledchris]

were the valves warm or dead cold when you did the adjustment?

id keep close track, if you can still, to where you are on the overall adjustment on that one - so you can run the motor a little bit to warm them up (to make sure the lifters are pumped up all the way) and then re-adjust that one warm. then see how far out you have to go to get your original 1 3/4 turns.

Colin apparently brought all this stinkin warm weather with him to Eureka, so it's too early and too humid for me to think more about this right now... :p the reality is that we get this fairly often in the summer, but just never when he's here. the schedule must be 'off' this year.

[vwlover77]

Welllllllll...... Colin says in his Hyrraulic valve adjustment procedure that cold or warm makes no difference and pumped up lifter or not makes no difference. All the adjustment does is set the position of the plunger in the lifter. That said, the engine was cold, but I ran it for 30 seconds or so to be sure the lifters were pumped up.

[Amskeptic]

Welllllllll...... Colin says in his Hyrraulic valve adjustment procedure that cold or warm makes no difference and pumped up lifter or not makes no difference. All the adjustment does is set the position of the plunger in the lifter. That said, the engine was cold, but I ran it for 30 seconds or so to be sure the lifters were pumped up.

If you had only 1/4 turn to "0" and it was only a few thousand miles ago that you set the preload to 1 3/4 turns, then you have either a lash cap that wasn't seated (likely), or a WEAR problem. Reset to whatever your favorite preload is, recheck in 500 miles and report back.
Colin

[Amskeptic]

Colin apparently brought all this stinkin warm weather with him to Eureka, so it's too early and too humid for me to think more about this right now... :p

100* today. Some One's messing with me.
Colin

[vwlover77]

Pre-load set to 1 3/4 turns. I will report back in 500 miles.

[vwlover77]

Whoops, I didn't realize I was driving the Bus this much.... 1000 miles later, the pre-load remained at exactly 1 3/4 turns as originally set. Whew!

[Amskeptic]

Whoops, I didn't realize I was driving the Bus this much.... 1000 miles later, the pre-load remained at exactly 1 3/4 turns as originally set. Whew!

Good.
Colin
(October pizza pass-through?)

[airkooledchris]

ive been re-reading all of the hydraulic lifter adjusting procedures again today - just to recap before I do it on my other bus now that ive ran it a bit.

I don't know why, but there is one lifter in my primary engine where it seems to like the warm adjustment. Every time I did them cold, that one would end up clattering really loudly afterward and for a while. But if I re-did that one warm, it would quiet down. At least I think it's the same one, it's hard to say. Every time I do an adjustment on that motor (engine) it seems to stay exactly the same as the last time I touched it, so it's hard to document 'no change again.'

there's one lifter on this other motor (engine), on the 3/4 side this time, that seems louder than the rest. im interested in seeing where they are all at currently, and weather or not it'll quiet down once adjusted or if it's waiting for that one really long run on the highway. (not quite road legal yet)

(thanking you in advance-despotic ENGINE editor)