procedure for adjusting valves

[zliminator]

what is the procedure for adjusting valves on a 350? The lifters are hydraulic. I will post pictures of it on my website within a few days.

 

zliminator

[zliminator]

I just did a search and found this:

 

"now if the lifters are hydraulic of course you just back the adjustment nuts off the rocker studs with a wrench, slowly until the rocker starts clicking , then slowly tighten the nut just up to the point that the clicking stops then add 1/4 to 1/2 turn to preload the lifter and move to the next rocker and repeat, the only differance with solid lifters is you use a feeler gauge inserted between the valve tip and rocker after they click slightly,to measure the lash distance recomended on the cam spec. card (normally .016-.028 thousands) and you tighten them just to the point at idle that the clicking stops... then you remove the feeler gauge and move to the next rocker

if your useing jam nuts dont forget to lock the allen key..."

 

I have some valve covers with the tops cut out. I'm going to tape some cardboard or plastic around the tops to keep splattering oil all over.

[grumpyvette]

I just don,t think adjusting the valves without oil pressure and the block up to operating temp. is the best way either so....

 

how do you adjust valves at idle without the mess of oil getting all over the engine and headers

 

HIT A FEW YARD SALES, SWAP MEETS UNTILL YOU FIND A DIRT CHEAP SET OF TALL CAST VALVE COVERS LIKE THESE, the CONDITION THEY ARE IN ,WITHIN REASONABLE LIMITS OF COURSE IS NOT THAT IMPORTANT

you simply cut the ribbed center section out of the valve cover, and glue the synthetic valve cover gaskets on them in the normal location,

when you go to adjust the valves you first remove the standard valve covers and install your VALVE ADJUSTMENT COVERS, they retain about 80%-90% of the oil that would normally be lost over the edge of the cylinder head while adjusting a running engine, they also catch much of the splashed oil, just leave a 1/4"-3/8" of the rolled top for strenth around the perimiter of the top surface. I bought my set for $10, they were old and slightly discolored but I could not care less! I took them home and used a drill and saber saw to remove the center ribbed area, theres several brands that are very similar in appearance, all will work! and Ive used them for over 25 years, if I remember correctly they are mickey thompson brand

 

now if the lifters are hydrolic of course you just back the adjustment nuts off the rocker studs with a wrench, slowly until the rocker JUST starts clicking , then slowly tighten the nut just up to the point that the clicking stops then add 1/4 to 3/8 turn to preload the lifter and move to the next rocker and repeat, the only differance with solid lifters is you use a feeler gauge inserted between the valve tip and rocker after they click slightly,to measure the lash distance recomended on the cam spec. card (normally .016-.028 thousands) and you tighten them just to the point at idle that the clicking stops... then you remove the feeler gauge and move to the next rocker

if your useing jam nuts dont forget to lock the allen key

 

 

[strotter]

There are a couple of schools of thought on valve adjustment - "static" and "dynamic". The static school says that valves are best adjusted with the engine off, incrementing the crank by 360 degrees between adjustments. Most manuals will describe this method in detail. I, on the other hand, believe that the "dynamic" or running adjustment is best - but then again, I'm the kind of guy that *feels more manly* when I'm covered in hot oil.

 

My procedure is as follows: prepare ahead of time by getting a factory-type pressed steel valve cover. Using a jig-saw, cut a square slot in the top of it approximately 1 inch wide the entire top length of the cover to within about an inch of the ends. If you have a center-bolt valve cover, be sure to not cut the flanges for the bolts. This slot will give you access to the adjustment nuts, while restricting the oil being slung around during the adjustment. Be sure it has a decent gasket on it - used is OK, but torn up is not. I glued a gasket on mine - make sure it's O2 sensor safe, if your motor is so equipped.

 

Next, prepare the motor. Move wires and hoses to positions out of the way of the valve covers. Restrain them with tape or wire ties or anything else that's convenient. The idea here is that you won't have to be fighting with them once the motor's all hot and toasty.

 

Have a couple of rags ready, as well as all your tools. Also, note that you *will* be doing this out-of-doors. Don't even try it in your garage.

 

Start the motor, and warm it completely. It'll warm faster if you drive it around for a bit - 10 minutes at least. The idea is that the motor is fully warmed up - not just hot under the hood, but fully warm. As soon as you get back and shut it down, you're on the clock.

 

Pop a valve cover off, and install the mutant one. Start the motor, but for goodness sakes, don't rev it - revving will sling oil right out of that cool slot you cut earlier.

 

Time to adjust. I use a 5/8" socket on a six-inch extension, to keep my fingers back from the moving parts and hot oil. Go to the first valve nut, and gradually back it off: four or five seconds for half a turn is about right. The motor will idle OK during this phase. At some point, a half a turn or so back, among all the noise and the heat and the wind from the fan, you'll hear the valve clicking. Watch it carefully to make sure *that's* the sound you're hearing - other noises can easily be mistaken for the click you're looking for. (If the valve is already making noise, you'll hear it get more pronounced as soon as you start loosening. Don't go too far, it's possible for the rocker arm to come off the valve stem. You'll also feel the click through youir socket). Once you hear it clicking, toggle your socket and start tightening. *Now* you're looking for the point at which it *stops* clicking. Go very slowly, you want to be accurate with this point.

 

So you've turned it in and it has stopped clicking. Think of this as an index point. Note the angle of your ratchet handle - that's "0" degrees. You can rotate it back to a more convenient angle, if you like. Now, very slowly tighten the nut clockwise half a turn (180 degrees). You may notice the motor stumbling here - as the lifter preloads, the valve isn't closing properly, causing the rough idle. The effect will go away in a few seconds, so you can keep on tightening until you reach the 1/2 turn. Or, you can pause for a couple of moments, until the motor smoothes out, then continue. The important thing is that you won't be rotating the nut any farther than 1/2 turn -if you go too far, you could (theoretically) pop the piston with the valve. I've never heard of anyone actually *doing* it, but I enjoy worrying about unlikely things.

 

Once you've got the nut turned in, you're done with that one. Move on to the next. The nice thing about a running adjustment is that it takes less time to do a bank than it has to read these instructions.

 

Once you're all done, you may notice a fine layer of oil on everything. That's what the rags are for.

 

As a side note, I try to do my valves when it's fairly cool outside. I don't like the heat, which can be extreme above a fully warmed up engine, but that's not really the reason. When I'm uncomfortable like that, I tend to hurry, and hurrying through any job like this is a BAD THING. A good way to screw up something, or get hurt. Take your time, do it right.

[zliminator]

Thanks GrumpyVette and strotter for the really helpful suggestions. Now, here's another question: I read the temp on each header and the one at the back on the passenger side is very hot - 500 degrees plus when it warms up. The others are within reason but I do see noticeable differences. I was thinking the valves were out of adjustment and it was causing this problem by not letting enough fuel into the piston. I was also thinking (someone told me) that it could also be a result of the piston before the no. 8 that had valves out of adjust and would cause a an airflow problem in the manifold. Guess there's one way to find out...

 

zliminator