Itinerant Air-Cooled

To the notch.

khargis wrote:Hello folks. Valve adjustment day. From what I have read and seen, the notch mark on the distributor where no. 1 fires should be in front. On mine, the notch is kinda pointing towards no. 4. When adjusting to TDC, to adjust no.1 exhaust, where will my distributor point to? Still to the notch or where the notch should be? Does this makes sense? Thanks kris

Just a bit of clarification here...

If memory serves, the notch is supposed to represent TDC (top dead center) of the number 1 cylinder, as we typically have the timing set ~ 7 degrees before TDC the spark plug is actually firing a tad before it reaches the top to allow the combustion process to occur. So if you had a clear dist. cap and could see the relation of the rotor, and the contact point in the dist. cap for the #1 cylinder and both of their relation to the notch, the rotor and contact point would be slightly before the notch. Make sense?

I think you mean rear of the engine. Rear faces the hatch, front of engine faces the transmission.

When valves are adjusted we are adjusting to TDC of the compression stroke when both valves are fully closed. If it was the exhaust stroke the exhaust valve would be open (wouldn't be able to get a feeler gauge in there if you tried) and the intake would be closed.

TrollFromDownBelow wrote:

khargis wrote:Hello folks. Valve adjustment day. From what I have read and seen, the notch mark on the distributor where no. 1 fires should be in front. On mine, the notch is kinda pointing towards no. 4. When adjusting to TDC, to adjust no.1 exhaust, where will my distributor point to? Still to the notch or where the notch should be? Does this makes sense? Thanks kris

Just a bit of clarification here...

If memory serves, the notch is supposed to represent TDC (top dead center) of the number 1 cylinder, as we typically have the timing set ~ 7 degrees before TDC the spark plug is actually firing a tad before it reaches the top to allow the combustion process to occur. So if you had a clear dist. cap and could see the relation of the rotor, and the contact point in the dist. cap for the #1 cylinder and both of their relation to the notch, the rotor and contact point would be slightly before the notch. Make sense?

I think you mean rear of the engine. Rear faces the hatch, front of engine faces the transmission.

When valves are adjusted we are adjusting to TDC of the compression stroke when both valves are fully closed. If it was the exhaust stroke the exhaust valve would be open (wouldn't be able to get a feeler gauge in there if you tried) and the intake would be closed.

Thank you and yes I did mean rear of the engine. The notch on my distributor is pointing toward no.4, more towards the front left. How does this affect my TDC?

Successful valve adjustment. No. 1 exhaust, very tight, will half to look up what that means. The rest of the valves required little or no adjustment, but did it anyway, just to get the feel. Thanks everyone! Step by step... Kris

It means you need to keep an eye on it. Define 'tight' ... what size feeler gauge did fit before you adjusted? I would check every 500 miles to see if it is holding adjustment. Report back your findings after 500 miles as to whether there was any change.

EDIT:
Also, in regards to your other post; that notch in the distributor is just to get you in the ballpark and that you are not 180 degrees off; you should be using the mark on your cooling fan pulley to find TDC on number 1.

TrollFromDownBelow wrote:It means you need to keep an eye on it. Define 'tight' ... what size feeler gauge did fit before you adjusted? I would check every 500 miles to see if it is holding adjustment. Report back your findings after 500 miles as to whether there was any change.

EDIT:
Also, in regards to your other post; that notch in the distributor is just to get you in the ballpark and that you are not 180 degrees off; you should be using the mark on your cooling fan pulley to find TDC on number 1.

Thanks for the response troll. Tight as in, my .006 gauge would not fit, next time I will try smaller gauges just to see how tight. Will keep posted at 500 mile mark. As far as the TDC post, I was using the groove on the pulley fan, just wasn't sure, because things I read and watched showed the distributor groove facing the rear. Good to know. On to finding vacuum leaks! Kris

Sounds like you are on your way! I found out last time I had adjusted my valves, that I had been adjusting them just a bit loose. I found this out, b/c I got the 'feel' I was looking for, but yet a .007 gauge would still fit underneath, so then tightened until .006 would fit, and the .007 did not fit. Believe it or not, that .001 made a noticeable difference in the low end responsiveness of the car. Just a thought/tip for next. time.

Wait a sec. Have you read the thread about adjusting hydraulic lifters? You and I have the same year bus and engine. I believe that you are adjusting them as though they are solid lifters. If I 'm wrong, please let me know. I can't find Colin's write up, so here is Ratwell's...

http://www.ratwell.com/technical/Hydrau ... adjustment

Jivermo wrote:Wait a sec. Have you read the thread about adjusting hydraulic lifters? You and I have the same year bus and engine. I believe that you are adjusting them as though they are solid lifters. If I 'm wrong, please let me know. I can't find Colin's write up, so here is Ratwell's...

http://www.ratwell.com/technical/Hydrau ... adjustment

Sure, ask me if I remember whether or not it is a hydraulic vs solid lifter engine . . .

Ratwell's write up has some issues with forcing people to pump up or bleed lifters when it is not necessary.

Try this . .
Front Page > Engine Forum > hydraulic valve adjustment procedure STICKY

viewtopic.php?f=46&t=11408#p199857


(p.s. khargis, don't worry about the notch on the distributor, we only need crankshaft pulley notch to be at "0" on the scale to adjust the #1 #3 valves, then use the double mark 180* away on the pulley to adjust #2 #4.)

As you have already figured out, the notch in the distributor means nothing.

Note where the rotor of the distrbutor is pointing to (as in the spark plug wire headed to the cylinder number).

Keep in mind the cylinder order....

FRONT
3 1
4 2
REAR

Thanks folks. They are solid lifters. Last visit with Colin, we adjusted them to .006. So, I retained that crucial info. Bus is running much better, still trying to find vaccum leak and look forward to August 5 visit with Colin in Boise! Cheers