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So, a question for you guys with steel push rods: how do you determine “zero clearance?” I don’t believe I have a .001 or .002 feeler to use as a “no-go.”

The first time I did my valves after Blackline did them, they were very tight. Next time I had my air cooled expert do them and they’re even noisier cold. I suspect I have steel pushrods and neither I nor my guy realized it.

^^That^^

You should be able, with dry fingers, to reach in and rotate the pushrod easily but with just the slightest rotational resistance.  That's zero cold clearance (ZCC).  But maybe you're not comfortable with things that tight.

When I do a check, I grab the end of the rocker arm and push it vigorously in and out.  If it "clicks" then I consider that OK, even though it's slightly more (maybe .001" - .002") than ZCC.  And, yes, my valves are a little noisy until things warm up - That's how I let my track-bike-neighbor know I'm going for a ride.

If it "clunks", then that usually means that the clearance is too wide and needs to be adjusted in.  If it doesn't click or clunk, then it's too tight (for me, maybe not Blackline) and needs to be run out to ZCC.

You will probably need to reinstall your distributor first to be sure you are starting at cylinder 1.  Do you have a degree crank pulley?  Instructions will tell you to start with the distributor rotor pointing at the notch on the rim and the pulley at 0.  Then adjust valves for cylinder 1.

Then, as the instructions say, rotate the crank pulley 180 degrees clockwise and adjust #4.  The sequence is 1, 4, 3, 2.

I usually go contrary to the instructions and rotate the pulley counter-clockwise and do 1, 2, 3, 4.  There is some risk of loosening the bolt holding the crank pulley.

Some people rotate things with a wrench on the alternator pulley.  I use a ratchet wrench with a very long handle on the crank pulley bolt.  My crank pulley bolt has a square hole I plug the ratchet wrench into.

@Gordon Nichols I don’t know exactly how tight Justin adjusted them, I just know the standard “Go” feeler wouldn’t go in any of them. I’m assuming they were perfect knowing Justin’s reputation.

@Michael McKelvey  Good news on the 3/8” slot in the pulley nut. That’s cool.

FWIW, I like to pull my plugs when I do my valve adjustment. Makes rotating the engine easier without fighting the compression and gives me a chance to check them out and re-gap if necessary.

And if I’m not mistaken. even the stock pulleys have notches at 0° and 5-8° (whatever the static timing is. Can’t remember)


@MarylandGuy Remember the crank rotates twice for every full compression cycle, so at the TDC mark, the #1 piston will be either at the top of the compression stroke with both valves closed and ready to adjust, or at the top of the exhaust stroke with the exhaust valve open, so if there’s any tension on the exhaust valve, you’re 180° off.* (This is why it helps to watch your dissy, if it’s in place. It only rotates once per cycle)

Once you get #1 done, it’s easy to do the rest in order. (Unless you do like I do and mess up and have to start over.)



*I say this because someone who prefers to remain anonymous has actually tried to back his open exhaust valve adjuster out.

Last edited by dlearl476

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Here's a YouTube video that shows how to do the valves, and a number of other basic maintenance chores. The first 15 minutes cover the valves.

You may or may not like the presenter (opinions vary quite a bit), but she explains things slowly and very clearly, for the beginner, and her photography is good, too, so you can see what she's talking about.

She has aluminum push rods, so uses a feeler gauge to set clearance (which you won't have to do with steel pushrods), but at least you'll see how the adjusters work. She also has a stock VW crankshaft pulley. Yours may look different, and may have slightly different marks, or may be marked all the way around in degrees.

There are lots of other YouTube vids, but you could do worse than this one.

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Don't poo-poo the stretched rocker stud. Make sure they're both screwed all the in.

But before that, remove them. Measure the length of the studs, make sure they are exactly the same length.

There is a reason it came loose, and I seriously doubt the engine builder forgot to torque the studs.

@MarylandGuy Glad you found the washer, and nut.

When I set loose zero clearance, the pushrod can be EASILY spun, no resistance. If there's resistance, that isn't "loose zero". Lots of valvetrain clatter is side-play of the rockers themselves. If the rockers are properly set up, the motor should be quiet.

The motor I just built has chromoly pushrods and properly set Berg rockers. It doesn't make any noise cold, and I really don't hear it warm either. The exhaust is loud, but I could still hear clicking and clacking if it was there.

Last edited by DannyP

I tighten things until I can rotate them with my fingers with just a little resistance.  I have to be careful to be sure it is actually rotating and my fingers are not just slipping in the oil.

Same here with my chromolies. The pushrods usually have a light coating of oil so to double check, I use Gordon's technique of trying to rattle the rocker arm against the valve stem.

If I get just a little bit of rattle when shaking them, that's where I like it. As Danny says, they are very quiet when they're right.

My AC guy says big performance engines are always louder than stock 1500-1600’s. It seems plausible, but I have my doubts.

btw, while we’re on the subject: Are pushrod tubes aluminum, steel, or tin?

While I was under my car today I thought I’d throw a magnet in the pushrod tubes and see if I could ascertain whether I had steel push rods.

The magnet stuck to the tubes, but less than the exhaust header. I figured if I had aluminum tubes and steel rods, the magnetism would be barely detectable. Am I chasing rainbows or is the tube just so thin it has less pull that the exhaust, and I need to pull one out to be sure?

Last edited by dlearl476

I tried to follow all of the great advice and tips here and got everything installed this evening.  Installed the distributor and aligned with the notch at valve #1, tapping it in to make sure it was seated really good.   Got all of the valves set to what I'm hoping is ZCC...  I went with pushrods able to spin with slight resistance and no clicking on a cold engine that hasn't started since yesterday afternoon.  Even with my new exhaust the engine crank sounded really loud before this whole situation so it will be interesting to see how it sounds with everything ZCC, assuming I got it right.

Everything is torqued in to spec now too. 

Only thing that was odd was on the passenger side the pushrods seemed really close to the tubes.  Perfect center on the driver's side.   See pictures below.   Alan checked his buggy (he still isn't retired like he keeps saying) and it was the same so hopefully ok.

Only thing I was missing was enough oil to fill it and start it up.   Will do that tomorrow and report back.  Huge thanks to all of you and hopefully this being documented helps others out in the process.

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@MarylandGuy 12mm head? Interesting, they should all be the same. I'd not have an odd man out.

I like to use the nuts that hold the heads on, they are a 15mm wrench size, spreads the load out across the rocker better. I install those without washers. I guess blue Loctite is OK there, as someone suggested above.

Looks like you may have to shim the rockers. Try first loosening all the adjusters. Then loosen the rocker nuts/studs. Try to slide the rocker over so the pushrods are more centered. If that doesn't work, you'll have to shim the rockers to center the pushrods better.

@MarylandGuy posted:

@DannyP just reread your point on the rocker studs.   I'll take it apart again tomorrow and check those.  Then I can do a second pass on the valve settings.

One thing that was odd was that the nut that came off was 12mm while the other 3 were all 13mm.  It went on smooth and tight so I don't think the pitch was wrong or anything but it was a different nut.   

Sounds like the builder used one if the special nuts for Carb manifolds on your rocker. Standard for that thread/pitch is 13mm flats, but they make 12mm bolts with extra clearance for a thin wall socket for the manifolds. Someone even posted that they’ve had 10 and 11 mm bolts on their manifolds and carbs.

I would make them all the same, like Danny said, just for consistency. For that matter, I’m just OCD enough that I’d make a trip to a good hardware store and buy 8 new Gr8 nuts and spring washers.

Here’s a thought: was the 12mm one the one that loosened up and came off????

Last edited by dlearl476
@DannyP posted:

I have seen 12mm on carbs often.

Yes, the 12mm was the one that came off. I'd go to the hardware store and buy 4 Grade 10.9 metric nuts.

The thread should be 8mm x 1.25mm pitch.

I bought a whole box from Wurth after fighting with the 13mm bolts on my manifold the first time I took it off.

Its such a PITA that if I can’t tighten the bolts all the way to finger tight with my fingers, I throw the nut away and chase the threads in the stud with a die.

I serious wonder it the lower surface area of the 12mm nut helped it loosen up and come off???

From David’s OCD Machinist’s Guide, pp 412:

When spring washers are made, they’re stamped out of a sheet of metal. The stamping process leaves one radiused edge on the top and a sharp edge on the bottom where the washer finally tore away from the sheet. That sharp edge should always go to the hard surface that doesn’t turn, not the nut. It helps the washer dig in,  like a star washer in miniature.

So looks like my adventure for the day is to pick up 10.9 grade nuts for the rockers and oil after I confirm the rocker studs are all the same length and in good order.

Not to get political here, but I was planning to pick up Valvoline VR1 20w50 oil.  I'm in Maryland and unlikely to do much winter driving.  let the games begin on other suggestions.  I'm really not that picky about it.

Last edited by MarylandGuy

Naaah......   The Valvoline should be fine.

Personally, I run 10W-40 but down where you have hotter summers the 20W-50 should be OK.

Most ACE Hardware stores have metric hardware (nuts/bolts) so you should be able to find the nut you need there - wavy washers, too.  Take along the odd nut to check the thread pitch on the new nut.  (But it sounds like you probably already knew all this, anyway.)

Last edited by Gordon Nichols
@MarylandGuy posted:

So looks like my adventure for the day is to pick up 10.9 grade nuts for the rockers and oil after I confirm the rocker studs are all the same length and in good order.

Not to get political here, but I was planning to pick up Valvoline VR1 20w50 oil.  I'm in Maryland and unlikely to do much winter driving.  let the games begin on other suggestions.  I'm really not that picky about it.

Yes(nuts), yes(confirm studs), and yes(good oil choice). Carry on, Paul.

@dlearl476 posted:


From David’s OCD Machinist’s Guide, pp 412:

When spring washers are made, they’re stamped out of a sheet of metal. The stamping process leaves one radiused edge on the top and a sharp edge on the bottom where the washer finally tore away from the sheet. That sharp edge should always go to the hard surface that doesn’t turn, not the nut. It helps the washer dig in,  like a star washer in miniature.

I always install even regular flat washers with the sharp/cut edge down, and the rounded edge toward the nut. Good practice.

Checked stud lengths and all the same, no bad threads.

Installed a new set of 13mm 10.9 grade nuts all around with washers flat side down, although a little hard to tell with the wave washers since they are thin.

Filled with oil and started it up.

Idles terrible and sounds poppy.  Video below.  Do I need to rebalance the carbs after this?   Maybe I have the valves set a little off or too tight (mine are steel)?   Poor first attempt at installing and aligning the distributor?

https://youtu.be/G_xVHHcO90g

Thanks guys, hopefully almost there because weather is absolutely beautiful today for a few test runs.

Last edited by MarylandGuy
@DannyP posted:

I always install even regular flat washers with the sharp/cut edge down, and the rounded edge toward the nut. Good practice.

Glad to hear I’m not the only OCD guy out there.

@Gordon Nichols My Ace had a great assortment of hardware. But it’s all the typical sizes. And their hardened stuff is pretty sparse. IIRC, those studs might be one step finer thread pitch than the common 8mm size. A good hardware store is hard to find. (You can tell when you first walk-in the door. They don’t sell barbecues and leaf blowers!)

It drives me nuts on my old Ducati, almost everything is a special fine size.

@MarylandGuy posted:

although a little hard to tell with the wave washers since they are thin.



The easiest way to tell on those thin ones is to hold them better thumb and forefinger and scrape them on your opposite thumb. Radiused side will be smooth, sharp side will drag like a razor. Especially useful when you’re installing them under your car where you can’t look down.

And as Allan suggested, most guys feel that total advance is more important than static 7.5° Have someone hold the throttle at 2500rpm (or, if you’re like me with no friends or family, adjust your idle screws up to 2500) and check your timing there. If you have a degree wheel-style pulley, great. If not, use a protractor and set a mark at 32°-35°.

A while back I visited a hardware store in Chagrin Falls, Ohio that opened in 1857.

The hardware where I grew up is closing after 90 years.  It's sad to see the non-bigbox stores closing.

When I lived in Las Vegas there was a pretty big hardware store that was an industrial supplier called Nut and Bolt. Their metric hardware section was almost as big as most Ace Hardware stores. I miss that place.

Nowadays, if Ace doesn’t have it, it’s  https://www.belmetric.com

Last edited by dlearl476

@MarylandGuy

Last video sounds fine.  They all click when cold and quiet down somewhat when hot.

Better to be clicky and loose than quiet and too tight and burn a valve.  I had an adjuster back off abruptly one day, and it sounded like someone was back there with a little hammer.

Like Alan, I am very impressed with your patience and tenacity.  We could be flip and say “look at how much you’ve learned”, but you’ve overcome a lot in a short time.  Hopefully, your pretty little car is done throwing mechanic’s lessons at you and you can enjoy driving it.  

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