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Tue Aug 08, 2017 12:11 pm

Hello, I have a 73 vw thing. I just got done rebuilding the top end of the engine. I replaced pistons, cylinders, heads on this engine purchased from jbugs. I put together the 1st and 2nd rocker arm assembly on first and then moved over to the 3rd and 4th. The assembly and the pushrods were good so i did not replace them. My problem is, once I installed the rocker arm assembly I noticed that my exhaust valves on 3 and 4 were compressed with the rocker arm adjustment all the way out. All the pushrods are exactly the same length and were the originals. I've tried everything including setting the backlash to .006 on #1. Counter clockwise 180, then setting #2 and the same for 3 and 4. The adjustment post is completely out and the springs
Are still compressed. Any ideas??

Tue Aug 08, 2017 12:39 pm

they do make shims that can go under the rockers.. usually when the case has been cut and heads cut.. this issues comes up.. but there are rectangle spacers available..

Tue Aug 08, 2017 6:02 pm

All I did, is swap old for new parts. No other work has been done to the heads or casing, etc. I'll look into the spacers too. Thanks

Tue Aug 08, 2017 6:06 pm

baker1428 wrote: All I did, is swap old for new parts. No other work has been done to the heads or casing, etc. I'll look into the spacers too. Thanks

something changed.. did they have them on there and you did not see them? got 4 square washers you cant account for were they went?

Tue Aug 08, 2017 7:55 pm

There are an awful lot of variables in these engines. Any chance that your old jugs were longer than your new ones? Did your old heads have a raised seating surface and your new one are instead cut flat?

Thu Aug 10, 2017 6:26 pm

@wildthing. That's it. The new heads were flat. Darn. I should of thought of that. I have spoken to a few people and they said at the last result use shims, spacers. Would you recommend using them and where can I purchase them?
Thanks guys for any and all of your help.

Thu Aug 10, 2017 6:48 pm

You can get barrel shims in different sizes and thicknesses

https://vwparts.aircooled.net/Barrel-Shims-90-5-92mm-Type-1-Set-of-4-p/90.5-92mm-barrel-shims.htm

Thu Aug 10, 2017 11:13 pm

Thank you so much.

Thu Aug 10, 2017 11:32 pm

You are going to want to set your deck height somewhere around 0.040" and once you get the heads buttoned down check your valve train geometry. You may still need to add something in the way of shims under the rocker supports.

Fri Aug 11, 2017 8:52 pm

Great!!! Going to tackle this on tuesday when im off.

Wed Aug 16, 2017 11:05 pm

Okay fellas, so I found out why my pushrods were too long. The intake lifter on #3 was stuck and #4 exhaust lifter was stuck as well. How they moved out a 1:4 inch is beyond me. I tapped on them with a brass punch while my buddy was turning the crank pulley. A little unorthodox but after I put the rocker arms back on and setting to .006, this engine is running perfectly. Of course I had to tune carb and timing but I figured it out. Thanks for all your help