Valve Adjust Question. .006 or zero???

Go to "loose" zero. You need to be able to spin the pushrod freely with the tip of your finger when that cylinder is at TDC, combustion cycle.

Depending on the cam grind, there may be noticeable valve lash ELSEWHERE during the cycle, some cams just aren't ground that even. I would personally make sure they stay loose the entire duration that the valve is supposed to stay close.

Valve clearance GROWS as the engine warms up, WITH STEEL RODS.

With aluminum rods it's the opposite, the clearance gets smaller as the engine warms up.

Jan

Wild Bill Tucker wrote:

Jan,

Do you have any idea of the valve clearance when the engine is hot with aluminum rods? Supposing that they were set correctly to 0.15mm with cooled engine.

Jan Anderss>

Joao

Not really. The factory recommandation was originally 0,10mm but people got lazy in the 70's and stopped maintaining their cars properly, and skipped valve adjustments. It was such a nasty task. If the valves were set to 0.10 and not cared for since, there presumably were cases where a neglected engine like this had clearances all over the place, some valves got tight and burned. So VW changed their instructions to 0.15mm to keep the lazy people's cars running without problems. Longer maintenance interval that way.

This leads me to think that 0.10 is normal when cold, and it shrinks down to almost zero when warm. It's a guess only. Maybe the better repair books would know.

Or Bob Hoover.

Jan

Joao Eliseu wrote:

Hey Jan , Bob Hoover did know better . Received a nice email from him. I also checked the archives via Google search and got a ton of info. Will play with the lash adj. (that doesn't sound right does it ? ) and see what works best for my little engine. BTW lots of priceless info in those Google searches ;-)

Be Cool.....AIRCOOLED !!

"Wild" Bill Tucker President Rare Air VW Club Pensacola, Florida '78 VW Bus ( "Old Rusty" ) '76 Bug "The Grape" '69 Squareback , Arizona car, Automatic

Rare Air VW Club Website:

Go Bob! You can pretty much trust what he says. Unless it's something about me ;)

Jan

Wild Bill Tucker wrote:

You can always set it cold and measure it hot - see the difference in your engine ! Rich

I thought that may be someone had already tested it. So, if someone checks the valves once a year and drives about 2000KM a year, it will be ok to set the clearance 0.10mm. I think it is a question of noise not a question of performance. Is this correct?

"tricky" wrote:

Joao

I've always used the 0.1mm (.004") on both my 1970 1500sp engine (that's it's original specs) and on the 1600 dual port engines, which had the 0.15mm (.006") specification, and have never had a problem of tight valves. The 0.1mm gives a slightly quieter engine, and so long as you adjust the valves every 3000miles (5k km), the smaller clearance works just fine.

I agree with Jan - the wider 0.15mm (.006") seems to be a setting to allow for less regular maintenance.

Rob Rob and Dave's aircooled VW pages