Had to change how I was adjusting valves . . .

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RobM
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Joined: Wed Oct 24, 2007 1:18 pm
Location: So Oregon

Had to change how I was adjusting valves . . .

Post by RobM »

First off let me say that I am a novice 'valve adjuster'. I've been having it done at the local bug shop. However, the economy has hit my job--along with everyone else's so I decided to start doing it myself.

I did my 74 1600 by following the instructions in J.Muir's book and didn't have any problems to speak of. So this morning I began on my '66.

Well, after about 5 times and the engine--obviously-- still running wrong, I got on-line and found a different method of adjusting them. It worked the first time.

But I'm left still scratching my head as to why my gaps kept coming out wrong?

Now I was a technician not a mechanic, but matching the pully's TDC nick with the line on the block-- adjusting #1 valves to .006 // turning the engine counterclockwise 180 degrees and adjusting #2's to .006 - - counterclockwise to the timing nick again to adjust #3 valves// then another 180 degrees to adjust #4 just doesn't seem like it could get fouled up.

Yet I'd fire the engine up and you could tell that it was out of adjustment.


I Found a different technique on 'VW Trends' magazine website:
Turn engine to line up TDC mark- pull both valve covers and adjust the valves that have movement (3 on one side and one on opposite side) // rotate engine one full turn- back to TDC mark and adjust the valves that have movement (one on the first side now and the other three on the second side) --end of adjustment.

Fired it up and it's running fine. But when I was adjusting it the new way, I was adjusting those valves a full millimeter. Now I was very careful to adjust them to .006 and used the .008 gauge as a 'no-go' gauge. It only took 15 seconds of running the car to tell me the adjustment was wrong. So how did they end up off in outerspace like that? :?

Any ideas would be appreciated.
volksbugusa
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Post by volksbugusa »

robm
hi...the valve adjustment a nice project to do... when you adjust the rockers you must remember to put slight pressure on the push rod ends...the only other factors that come into play if the adjustment is not holding after the motor runs and cools off is
bad bearings on the crank or cam shaft
worn lobes on the cam
bad timing which is creating to much heat the motor is expanding out of spec...what is the timing?
if you need more help pm me we can talk on the phone...

matt
Blue Baron
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Location: Tampa, Florida

Post by Blue Baron »

I've always used the Muir method, which is the Volkswagen factory method. I'm still trying to wrap my head around the VW Trends method you described. I guess I'd need a demo.

At any rate, the question that comes to mind is, what mark on the pulley were you lining up? It sounds to me like you may have been off. Try doing this, remove both valve covers, and when you go to set the valves on one cylinder using the normal method of setting the mark on the pulley to the seam in the case, watch the rockers on the opposite cylinder. Example: You're adjusting No. 1 so look at No. 3. The intake and exhast rockers will be opening and closing opposite one another. Move the pulley back and forth, and when the rockers on No. 3 are exactly even, you're ready to set the No. 1 valves.
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