Another small block mess!

Ok, got a typical small block Chevy, had the "puff" at startup, compression shows good and even, so I'm thinkin' valve seals, since it had set around for awhile. Got to the part where you adjust the lifters, pushrod rolls finger tight ect. Book says to crank it down a full turn after that. Trouble is, after about a 1/4 turn the valve starts to open????!!!!>>>""?? I'm using the compressor method to hold the valve up while working, and you can hear the air start to seep out......Whats up with that?????????

 

if you have the springs and keepers on you don't need the air anymore. is your cam in the right spot? i only turn mine between 1/2 and 3/4. it may open a little until the lifter compresses.

 

another thing people get confused on is the push rod deal. you tighten the rocker nut to take the slop out between the push rod, rocker arm and lifter. then turn the nut 1/2 to 3/4 turn. realy dosn't have anything to do with rolling the pushrod in your fingers.

 

give it a moment to bleed out the oil in the lifter you just displaced.

 

For hydraulic lifters, with the cam lobe on the base circle, I tap the rocker arm up and down on the valve tip while tightening the lock nut. When the tapping noise stops I go 1/4 turn. If you are not on the base of the cam lobe you need to get there before adjusting the valves. Easy way to do it if you can get to the front of the engine is to turn it over until the pushrod is all the way up, mark the balancer and timing tab, then turn the engine over 360 degrees. Repeat for each valve. Valve spring will hold the valve closed, no need for compressed air.

 

Set them at 1/4 turn and then rest with it running.

 

You are right about the valve seals and the puff of smoke, but dont worry it will run fine and not give you any trouble. Im not sure I follow you on your valve adjustment? Are you putting air into the combustion chamber to adjust the valves? That is not nessesary, all you need to do is rotate the engine so the lifter is the closed postion. then do your zero valve lash and then add the lifter pre load. Do you know what type of lifter is in the engine? Is it possible that it is a solid lifter cam?

 

there is a tool that screws into your sparkplug hole that you hook your air hose to. that will keep your valve from falling into the cylinder while you take the spring off and change the valve seal. so you don't have to take the heads off.

 

This is what I do also. I gently lift the push rod up and down, until all play is gone, then another 1/2 turn. This is with the lifters pumped up, and lifter on low part of cam.

Same basic as quoted, it is the only proceedure that works every time. and no mess

 

In a pinch you can use a length of 3/16"-1/4" nylon rope to pack the cylinder then bring it up on the cycle , it will hold the valves from dropping.

 

I'll bet the lifter is not bleeding down, cause some stopped leaking after a few seconds. I'll adjust as you guys have suggested and let er' rip!!! I haven't done a seal job in years, i guess my brain moved all that memory to trash!! Thanks guys!!!

 

Also , I'm tryin' to keep the flame alive. This car is built for my grandson!!!!

 

back in the day fixing air planes, to replace a valve seal or clean a sticky vlave guide i used a piece of rope into the cylinder thru the plug hole rotate the crank up tight to hold the valve and remove the spring and keepers,very easy and much better than air no matter what, it stays put.as far as valve lash they covered that