Hi fellas, I did a running valve adjustment on my hydraulic flat tappet equipped Pontiac 326 today. I had installed Chevy 3/8-24 self-locking nuts on each rocker stud and adjusted each about 1/4 to 1/2 turn of the nut after ticking stopped and it sounds great. Here's my question. I have one single valve (#2 intake) which after I shut down the engine and right after startup will tick for about 2 seconds then go quiet like the rest. I started and stopped the motor several times today with the same result. Ever have this happen?
New hydraulic lifters are a crapshoot, it sounds like you have one that bleeds off pressure, very common.
Hydraulic lifters on a Pontiac V-8 with stock cam and rocker arms don't adjust like a small block Chevy. I believe the rockers are just fully bolted down to a specific torque reading with the engine not running. Check your shop manual for more details and specs.
These lifters only have about 150 miles on them. Maybe some assembly lube got in it. I like the idea of cleaning and possibly repairing the lifter without replacing it. Not crazy about having to pull the manifold and valley pan again though...
Or you could just live with the tick. An old heap trick that we used to do was dump some ATF in the oil when the lifters were ticking. You may try that it won't hurt your mill at all and if that don't cure it then take it apart at your next oil change. Half a quart ought to do it. Avoid using type F.
The Ford Transmission Fluid works but you need to get the old stuff. Look for people who collect old bottles.. Rislone also works well. It's one of those magic additives that really works..
Is this along the lines of the Marvel Mystety oil? And what does it do? Clean out sludge or assembly lube?
Rislone makes the moving parts extremely slippery. Its truly amazing, right after pouring a quart bottle in the engine, its like you added 20 horses or should I say whales since this is cooked down whale
Add a quart of Type F transmission fluid. Run it for around 100 miles, (2 hours) dump the oil and filter. Or add a quart of Marvel Mystery Oil. Run it until the next oil and filter change. I worked at a shop in the eightys that would do that process for dirty or unmaintained engines in gasoline work trucks. I was always amazed at the positive results. I still enjoy the smell of MMO.
Thank you fellas, I appreciate the advice. I think I'll try that in about 350 miles after my 500 mile break-in is done if the tick hasn't gone away by then.
All those tricks were for used sludged up engines. Sounds like you have a new clean engine so I bet the tricks will not work.
Sorry I apologize ahead of time. I would never put trans fluid in an engine for any reason. Or Marvel MYSTERY oil. Lippy
When adjusting, try 3/4 turn past zero lash, 1/2 turn or less if racing. If it's going away pretty quickly, likely a bad or loose lifter ( bleeding down to quickly ). Poor machining on the inside.
I believe this was part of the old Wildcat tuning procedure back in '64, if I'm not mistaken. My mentor back in the '70s was a Pontiac mechanic from Indy and he turned me on to this long ago. What was called zero lash adjustment back then. Joe
I've heard of pulling the valve cover, dripping solvent, penetrating oil, MMO or whatever your pleasure down the pushrod to get to the lifter. Never tried it myself.
At - 1/2 turn, why not just run the nut down all the way till it hits the bottleneck? You really haven't gained anything using Chevy crimp nuts. Except maybe a few new new clicks ;-) ..... 1/2 , 3/4, bottomed out.. Hydraulics aren't fussy. Modern ones don't pump up with RPM like the early Pontiacs did.
Not likely your problem but I'll mention it.. I bought a new Chevy truck in '96. Right out of warranty it developed a lifter tick on startup that went away. Until one day it didn't. Not being familiar with newer maze engine compartments, and hoping for warranty, I took it in to the dealer. According to them, the new orange coolant they came out with ate the intake gasket, which leaked coolant onto the lifter below the leak, causing the problem for some reason. Cost me $1,300. Sounds like yours might be below a coolant passage, might want to at least tighten the bolts. BTW this coolant issue became widely known, there was a petition for GM to cover it but I don't think it ever came to fruition.
Valley pan seals that area on a Pontiac V8..Intake leaks run down the back or collect on the pan , below the bypass..
Ah yes, my mistake. I agree with what you said earlier though, I wouldn't hesitate to tighten it down further.
Rocker studs, ARP 290-7201, 1/2"-13 on bottom, 7/16"-24 top. There used to be some sold that were 1/2"-13 bottom, 3/8"-24, top drilled for oiling, but I'am not sure you can find them anymore. Pinning the studs works but requires a steady hand when drilling. If, after you adjust the rocker it comes loose again, this is a sign the stud is pulling out, a straight edge can confirm this also. Your problem seems to be in the lifter itself, as the adjustment doesn't change once the engine gets up and running. Adjustable nuts or pol-locks is a good way to even out valve length and seat variances when the heads have been worked on a few times. After all these years, its getting hard to find parts that still work with stock nuts and studs on Pontiac's.
HRJ I fought a "tick" in my HEMI for a long time, going with different weight oil, etc. I never have believed in the snake oils on the market but finally thought oh what the hell and bought some "Marvel Mystery Oil". That really did the trick. It runs so quiet now it is really nice.
Lippy, not picking on you, but why wouldn't you run transmission fluid or MMO in your engines? To my understanding transmission fluid is thinner and has more detergents which assist in freeing up stuck or dirty parts when used in a gasoline engine.