VW Rocker arms: Loss of power due to broken adjuster. Install 'em right!

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N8053H

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Tony those are not stock valve adjustment screws, those are aftermarket swivel feet adjustment screws. Because they are longer between the rocker arm and the valve stem they require a spacer under the rocker arm. If I remember correctly the thickness of the spacer is .062 . As you can see in the ad the spacers come with the swivel feet screws.
I have use those but took them off and used the stock VW screws. The stock screws hit the valve stem face slightly off center to slowly rotate the valves when the engine is running. The swivel screw that I had seem to hit the valve stem face more in the center so I didn't know if the valves were rotating correctly so I went back with the stock replacement screw. Never had any problem with the stock screws.
http://www.cbperformance.com/product-p/1523.htm
Pops those square spacers must be the spacers you mention that are .062. I believe I saw those when I took this apart but not real sure. I should have taken pics when I had this apart. If those spacer are in place, what do I need to do to correct this? Where can I get stock feet or screws for this and not the ball style. I did notice my 1/2 vw uses these same feet or screws or the swivel type.
What is your position on the springs. They all have the yellow to the top, this one the yellow paint in on the opposite side and not seen in the pic. But it is at the top.
Thanks again for the advice.
Tony
 

N8053H

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Some very good info here. I am ordering blocks today. As to making these. If I had access to the different size of stock in terms of thickness, I would make these. But not real sure how I could take a chunk of aluminum and make matching sets. Not without some machine tools. I have basic hand tools.

As to valve rotation, I have no idea what style of valve is being used in this engine. Some valves rely on the end of the valve that when hitting the rocker it will rotate. Some valves use a ball and spring built inside the valve itself. Some use other methods. But one thing, they use something to make the valve rotate. If the valve does not rotate it will burn or get carbon build up. Intakes get carbon, exhaust burn. The rotating of the valve keep it clean and also helps in cooling of the valve seat face. This is why one should use a bore scope to look at the valves. You will see if the valve stopped rotating or is not rotating. Saying this. I don't own a Borescope. But they are getting cheaper. The one you would want is one that you can adjust where the end is pointing. But this is another subject for another thread.

Thanks again every one for the help. When I install the new blocks I will take pics and update this thread.

Tony
 

N8053H

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I was working on a 1/2 Mosler engine a few weeks ago. Adjusting the valves for a friend. I noticed his rocker arms were offset from the valve stems. Not a lot but a little. I believe Pops is right and this offset rotates these valves. As you see from the pics and as Pops mentioned. The ones I am using hit right in the middle. When this engine goes to Scott Casler I will question this.

Tony
 

Pops

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Some very good info here. I am ordering blocks today. As to making these. If I had access to the different size of stock in terms of thickness, I would make these. But not real sure how I could take a chunk of aluminum and make matching sets. Not without some machine tools. I have basic hand tools.

As to valve rotation, I have no idea what style of valve is being used in this engine. Some valves rely on the end of the valve that when hitting the rocker it will rotate. Some valves use a ball and spring built inside the valve itself. Some use other methods. But one thing, they use something to make the valve rotate. If the valve does not rotate it will burn or get carbon build up. Intakes get carbon, exhaust burn. The rotating of the valve keep it clean and also helps in cooling of the valve seat face. This is why one should use a bore scope to look at the valves. You will see if the valve stopped rotating or is not rotating. Saying this. I don't own a Borescope. But they are getting cheaper. The one you would want is one that you can adjust where the end is pointing. But this is another subject for another thread.

Thanks again every one for the help. When I install the new blocks I will take pics and update this thread.

Tony
My grandson just bought a borescope that works with your phone, cheap and works good.
 

Pops

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Building a VW engine is sort of like building an airplane. If you go away from everything stock, you are on your own. Its where a lot of people have trouble, they just throw the after market non stock parts together and then end up with a poor running and unreliable engine and don't know why. It saves a lot of headaches if you buy the parts from someone like Great Plains or Humble Engines because they have to go through the trouble of weeding out the poor quality junk parts. Example -- To make a VW full flow oil to the oil cooler and filter you need a oil pump cover with a outlet for a oil line. Bought one from GP's . It was warped .008 on each corner, and with a .004 thick gasket it make a .004 oil leak. Complete junk, I called Steve and let him know and check his stock. I have a local friend that is retired and has a very well equipped machine shop at home and he fixed it for me. That is a problem that Steve and Scott has to deal with. The quality of some of the parts can be all over the place. They try to weed out the bad parts but one batch of parts can be very good and the next shipment can be something different.
At least buying from them gives you a head start and there prices are good. Hope the new owner of GP's is as good in running the business as Steve was.
 

N8053H

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Pops again great info. My Full vw uses both a remote filter and oil cooler. When the oil is cool it runs around 50 lbs. Once warm she is lucky to see 30 lbs at WOT of 3000 rpm's. I was taught as long as you have 10 lbs pressure for every thousand RPM's you are good. But I believe a little higher oil pressure would be nice.

But everything you mentioned Pops, this is why I send my engines to Scott of Hummel Engine. He knows what to look for and what will work and won't work.

Tony
 

Dana

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Some very good info here. I am ordering blocks today. As to making these. If I had access to the different size of stock in terms of thickness, I would make these. But not real sure how I could take a chunk of aluminum and make matching sets. Not without some machine tools. I have basic hand tools.
If you're talking about rocker arm shims, you don't need machine tools, just tin snips and a drill to cut them out of sheet metal. That's what I did when I was still in high school to fix the valve clearance in my sister's car after the valves were ground. I had no idea it was a standard thing to do, it just seemed like it would work, as it did.

I don't recall how the arms lined up with the valves in the Mosler in my Fisher. I do recall that the rocker shaft support was part of the head casting, no way to shim the rockers in that engine. Fortunately I never needed to.

Everything I learned about half VWs when I had the Fisher I now have to learn all over again about the O-290 in my new plane. It too has solid lifters that require adjusting.

Dana
 

Pops

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Some very good info here:

[video=youtube;GRGFHKYF7Cw]https://www.youtube.com/watch?v=GRGFHKYF7Cw[/video]
This is where a lot of VW engine builders get it wrong for a poor running engine.
 
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