what is the stock valve adjustment on type 1 some say 4 and 6 others say 4 on both bill.
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what is the stock valve adjustment on type 1 some say 4 and 6 others say 4 on both bill.
004..however on a fresh motor it is better to have them set a bit loose than have them tighten up on you.
I've got mine at .004, on the advice of the builder. Stock VW Bus heads with the usual port and polish treatment; nothing special.
I thought that our on site "experts" recommended .004 for intake and .006 for exhaust. Both my Bentley Manual and the John Muir book say .006 for both. My understanding is that looser means more clatter and a SLIGHT reduction in power, but also is a hedge against burned valves. These specs are for a stock engine.
ps. look for writeups
by Larry Jowdy and George Brown on this subject in the Knowledge section
ps. look for writeups
by Larry Jowdy and George Brown on this subject in the Knowledge section
It definitely depends on the individual engine specifications. Pat Downs at CB Performance recommends .002 for his engines, but I've been told to set them to .000 by several people IF you have chromoly pushrods. Interestingly, the method for setting the clearance at .002 that Pat describes sounds exactly like the method for setting it at .000 that I've been told. Go to the CB Performance website to download the engine maintenance tips from Pat Downs for that procedure.
As Lane Anderson said .000-.002 in. is specified by C.B. Perf....
The "trick" is the chromoly push rods...They don't expand as much as the Mag. case and aluminum heads...When everything is hot you have tons of clearance....Just listen........It's not a hay baler....
The "trick" is the chromoly push rods...They don't expand as much as the Mag. case and aluminum heads...When everything is hot you have tons of clearance....Just listen........It's not a hay baler....
Quick question---does it matter if you put the rear of a Speedster up on ramps to make it easier to adjust valves? Must it be level on the garage floor? Does it matter? I read something on this before that seemed to say don't raise the real when adjusting valves but can't find it now. Thanks for info----Jack
Jack: It doesn't matter....ramps or jackstands are fine.
~WB
~WB
As friend and uber-guru G.N. has explained, start w/ #1 and turn the motor BACKWARDS (using wrench on fan pulley) to get #2, #3, #4, in that order. Looking down on the motor, that will be starting at upper (forward) right, and moving in an orderly way around clockwise. Be sure engine is at either TDC (#1, #3) or BDC (#2, #4) each time. If you jack the back up too much and you might get some oil in your face, but the valves will not know or care. Did we mention to put the trans in neutral? The CB method is to just tighten the set screw 'til the push rod can't be turned by thumb and finger, then back it off just a skoosh (?) until the push rod can be turned easily. Tighten lock nut (don't move anything else) and check again. This for the chromoloy (?) PRs only. "Ordinary" PRs (whatever that means) are 0.004" IN, and 0.006" EX, as described.
A Formula One driver once told me to adjust valves on the slightly loose side. As quoted: "Better to hear them than smell them".
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Bill:
A lot of good (and sometimes confusing) info here, so let me sum up for you:
A STOCK, 1600cc VW Type 1 engine with stock, aluminum push rods is best set at .004" Intake and .006" exhaust. Going to .004" on BOTH intake and exhaust is often OK, but you have to re-check the valve clearance every 3000 miles to make sure the valves don't get too tight, otherwise you'll be paying for a valve job, especially if the exhaust valves burn - not a good thing. Paraphrasing what Nolan said, "Better to hear valve noise than replace burnt valves"
High-performance and racing engines often have different (chromoly steel) push rods. These push rods act a little differently in high performance engines, and they can tolerate a tighter setting of the valve clearance. Chromoly rods are usually set at .002" (I think Lane alluded to that up above), but they still should be checked every 3000 miles (or whenever you change your oil).
If you don't know what you have for push rods, then no big deal...use a small magnet to just touch the side of the push rods. If it sticks, they are chromoly steel. If it doesn't stick, they are stock aluminum. It's OK to set valves with chromoly rods at .004 (I) and .006 (E). Nothing bad happens, other than a slight increase in valve noise.
Hope this helps....gn
One of the "South Carolina Speedstah Guys",
freezing his valves off in New England
A lot of good (and sometimes confusing) info here, so let me sum up for you:
A STOCK, 1600cc VW Type 1 engine with stock, aluminum push rods is best set at .004" Intake and .006" exhaust. Going to .004" on BOTH intake and exhaust is often OK, but you have to re-check the valve clearance every 3000 miles to make sure the valves don't get too tight, otherwise you'll be paying for a valve job, especially if the exhaust valves burn - not a good thing. Paraphrasing what Nolan said, "Better to hear valve noise than replace burnt valves"
High-performance and racing engines often have different (chromoly steel) push rods. These push rods act a little differently in high performance engines, and they can tolerate a tighter setting of the valve clearance. Chromoly rods are usually set at .002" (I think Lane alluded to that up above), but they still should be checked every 3000 miles (or whenever you change your oil).
If you don't know what you have for push rods, then no big deal...use a small magnet to just touch the side of the push rods. If it sticks, they are chromoly steel. If it doesn't stick, they are stock aluminum. It's OK to set valves with chromoly rods at .004 (I) and .006 (E). Nothing bad happens, other than a slight increase in valve noise.
Hope this helps....gn
One of the "South Carolina Speedstah Guys",
freezing his valves off in New England
Enjoy the snow headed your way Gordon !
You guys said it all! Since I have chromoly pushrods I go for zero lash and check adjustment every 3K miles when I change the oil. Works out good.
Proper technique for ZERO lash.... adjust the rocker screw until there is no back and forth movement of the push rod, and it still spins freely between thumb and finger.(key word is "FREELY".)