roland g caldwell

Help my 1973 vette 350 eng 190 horse. lifters our very load when I first start the car, after 15 or 20 min the noise gos away. this nosie is only on one side. I have read the vette manual it talks about rotate each push rod untill the rod becomes some what tight then thigt one more full turn. Is this wright for my car. thank you Roland 7-6-12

prestige6

Make sure your valve is closed,then rotate pushrod until you start to feal a little tension. I would only go a half turn after that...You can adjust all your valves with just two revalutions of the motor # 1 Cyl & # 6 . I don't have the sequence handy right now.

Mike Ward

Sounds more like an exhaust manifold leak than lifter problems.

7T1vette

Roland...

The description you gave for setting the lifter/valve adjustment is approximately correct. But, the pushrods should not ever get "tight". What you are trying to find is the "zero lash" point where all of the excess slack in the system has been removed. Folks who are very experienced use the "spin" method of finding that zero-lash point; folks less experienced seem to find that point better with the "shake" method. Once the lifter is off the cam lobe [closed-valve condition], shake the pushrod up and down as you slowly tighten the adjustment nut. When the 'slack' in that movement is removed, you have found the zero-lash point. Now tighten the nut another 1/2 to 3/4 of a turn CW. This is when the valves are set with the engine NOT RUNNING. GM specifies one full turn, but that is on a running engine.

74modified

I always like to adjust them with the engine running. Just call me old school, but I think it is easier to get them accurately done with the lifter pumped up at idle oil pressure. It is a little messy, but I have an old cut down valve cover and little clips that fit over the lifter oil ports. At idle back off the nut until it "clacks", tighten until noise stops, then 180 deg turn.

oldalaskaman

this is the best easiest to understand tech for this I've seen , respectfully, bob

resdoggie

I have had exhaust leaks and it does sound like lifters ticking. Check your exhaust before going any further.

billla

First thing to check, for sure; lifter noise typically doesn't go away after warm-up

Indiancreek

Just get each cyl. on the cam flat and see if any push rods will spin or rattle. If not start looking elseware. All good advice so far.

L88Plus

Forget the "spinning the pushrod method". I've had more than one that fit the cup in the rocker arm so perfectly that I could spin it easily at 3 turns past zero lash.
Rattle it up and down and tighten the rocker nut until there's no rattle, then your choice of 1/2 or 3/4 more turn.
Do you have conventional rockers or are they aftermarket/rollers with oddball looking nuts on top? That's a different animal when it comes to securing it in place.

diehrd

Heat riser .. A lifter noise is usually a constant noise , and not usually solved by an adjustment unless it is a fresh build or fresh cam and your setting things up.

Roco71

The spin method has contributed to so many over tighten lifters.

oldalaskaman

yes , but for someone with no experience , I like it.

billla

The spin vs. shake debate goes on - both good ways; I've shown dozens of folks how to adjust valves and no one has ever had a problem with spinning the pushrod to accurately find zero lash just by letting them try it themselves. The "trick" as such is to stop at the first hint of drag...and not when the pushrod stops spinning or gets hard to turn - which as noted is well past zero lash.

If you can feel the difference between dragging your finger through the air, and dragging it across a tabletop...you can use the spin method successfully if you so choose.

Many folks have no problems using Lars' excellent whitepaper...which talks through this approach...so it's not that hard to learn from typed instructions

The best way for someone to learn is just to get the engine positioned correctly and experiment a bit on one valve - back off and turn down a few times until they get the hang of it

Indiancreek

The "trick" as such is to stop at the first hint of drag...and not when the pushrod stops spinning or gets hard to turn - which as noted is well past zero lash.



Exactly

Big difference between drag and tight.

7T1vette

Anyone can use either method, IF that person is actually watching someone else do it. But, for those asking for instructions over the internet, the "spinning" method is very difficult to describe CORRECTLY using a keyboard.

[That's my story and I'm stickin' to it....]

oldalaskaman

amen brother, amen

diehrd

Has anyone read posts or are they just gonna tell someone to adjust lifters because they have discovered a way they can debate . Spin , push pull ,, bla bla bla SHUT UP ..

He has an issue which is most likely NOT A LIFTER ISSUE.. So how does he get rid of his issue lifter debaters

oldalaskaman

op could go to harbor freight, buy a $4 mechanics stethoscope , and pinpoint his issue location for better help, or he could use the long screwdriver trick, or my favorite , the broom handle to the ear trick to also pinpoint the location of his issue. I would only point out that his title for the thread was ..lifter adjustment....possibly why they're arguing...lifter adjustment. hope this helps.

dmruschell

I'm not an expert, but I thought that hydraulic lifters didn't need adjusting, and I'm pretty sure a corvette engine with less than 200 horsepower made in 1973 would have hydraulic lifters.