sbc valve adj question.

[buZy]

Would like to check my valve adjustment and I have two questions actually.

 

Is there an easy way to tell if my engine has hyd or mechcanical lifters?

 

With either one being the case, where can I find out the process to adjust them the proper way?

 

Thanks!

[dr_hunt]

If they are mechanical, when the engine is running, you can hear clicking noise in the valve cover area. There are other ways to tell if they are hydraulic, one is when you adjust the nut down with the engine off you will see the pushrod move down instead of the valve opening.

 

Adjustment of either is fairly simple, two methods for hydraulic, one is with pointer on TDC #1 compression adjust #1 valves to zero lash, rotate engine 90 degrees and follow firing order repeating procedure for each cylinder. When you are done you can adjust all the nuts anywhere between 1/8 and one turn. Circle track racers typically run 0 lash to rpm higher so they don't get lifter pump up, but with today's hi-tech lifters that isn't so much of a problem. One turn will ensure that unless the cam is flat, it'll never need adjusting, IMHO I go 1/2 turn down from zero. The other only works with stock cams and that is TDC#1 compression adjust half the valves, I don't have the sequence and rotate one turn and adjust the other half. Chevy tech manual has the sequence.

 

Mechanical cams is the same as the first procedure mentioned except that you adjust to a lash specification which can be as little as .012 or as much as .030. Solid lifter cams typically produce 3 to 8 percent more torque than similar grind hydraulic cams through the rpm range, but for the street they are not as desireable unless you like to spend alot of time wrenching on the car. When using stock valve train, durability of the rockers becomes an issue and you have to check the rockers for wear pretty often.

[grumpyvette]

ok how do i adjust them now?

 

http://www.thedirtforum.com/chevyvalves.htm

 

http://www.2quicknovas.com/happyvalves.html

 

http://www.jimcookperformance.com/TechNotes/TN7ValvLash.html

 

http://www.centuryperformance.com/valveadjustment.asp

 

http://www.babcox.com/editorial/us/uhs89720.htm

 

http://www.boostandfuel.com/support/setting_valves.htm

 

http://www.carcraft.com/techarticles/87998/index2.html

 

http://www.angelfire.com/fl4/pontiacdude428/valveadj.html

 

btw if your totally new at this the tappet feeler gauge measures the lash clearance between the valve and rocker on solid lifter cams

 

I just don,t think adjusting the valves without the oil pressure and the block up to operating temp. is the best way to adjust valves , but yes you can do it just fine with several methods discribed above

 

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

 

 

 

Valve Adjustment: ENGINE OFF!

 

with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve

with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve

with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve

with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve

with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve

with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve

with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve

with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve

 

Exhaust Valve Adjustment: ENGINE OFF!

 

If you have noticed, this is the same procedure as the intake valves listed above, just that you are now adjusting the exhaust valves the same way.

 

with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve

with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve

with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve

with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve

with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve

with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve

with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve

with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve

 

or if your really lazy (you can use this method on hydrolic lifters)install the tall cut valve covers and just turn the engine about 20 degrees (start anywhere )and take the slack out of any loose rockers, repeat for 720 degrees,(twice around) then go back and give each rocker nut one turn OUT(LOOSER) and start the engine,(yeah it will be messy and noisy) and then go back and turn each rocker IN (TIGHTER) untill it just quits clicking plus 1/3rd of a turn past that point

 

 

 

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[buZy]

Thanks for the info everyone!