Bus missing

Ok, well, the bus isn't really missing. I know where the bus is, it's in the garage. But the engine is missing. No, wait...I know where that is too. No, I mean when I drive, the engine misses.

A little history. You all may recall I was building an engine for the bus this summer. Different bus, that one went to my son. Now I've just built and installed a new engine for the new '71 bus (It's white too, but without all the rust highlights). I decided to put the SVDA distributor on it, with compufire points. I'm using the 30/31 carb. So here's what happens. I tune it up as per the delivery directions from Aircooled.net, to about 40deg btdc at 3500 rpm (I've played back and forth with it all the way from 22deg to 41 deg at speed with no significant change). It sounds mostly ok, but there's a faint miss here and there. And watching the degree pulley I put on it, the mark dances around a little, but not much. But when it gets good and warmed up, it's much worse. In fact, after about 30 minutes of driving time it starts to miss real bad intermittently. I put the timing light back on it at the rest area, and not only does the timing mark jump all over the place, but the strobe is intermittent too. When I first put the whole thing together, I wired the input to the coil to the wrong terminal, and trashed my compufire points. I replaced them, but I'm wondering if I also damaged the coil. Anyone have an idea? Am I barking up the wrong tree? Should I even be barking up a tree? I'm going to recheck my valves now, and check over things a bit.

Glenn Roesener Air-cooled, as God intended

Ok, well, the bus isn't really missing. I know where the bus is, it's in the garage. But the engine is missing. No, wait...I know where that is too. No, I mean when I drive, the engine misses.

A little history. You all may recall I was building an engine for the bus this summer. Different bus, that one went to my son. Now I've just built and installed a new engine for the new '71 bus (It's white too, but without all the rust highlights). I decided to put the SVDA distributor on it, with compufire points. I'm using the 30/31 carb. So here's what happens. I tune it up as per the delivery directions from Aircooled.net, to about 40deg btdc at 3500 rpm (I've played back and forth with it all the way from 22deg to 41 deg at speed with no significant change). It sounds mostly ok, but there's a faint miss here and there. And watching the degree pulley I put on it, the mark dances around a little, but not much. But when it gets good and warmed up, it's much worse. In fact, after about 30 minutes of driving time it starts to miss real bad intermittently. I put the timing light back on it at the rest area, and not only does the timing mark jump all over the place, but the strobe is intermittent too. When I first put the whole thing together, I wired the input to the coil to the wrong terminal, and trashed my compufire points. I replaced them, but I'm wondering if I also damaged the coil. Anyone have an idea? Am I barking up the wrong tree? Should I even be barking up a tree? I'm going to recheck my valves now, and check over things a bit.

Glenn Roesener Air-cooled, as God intended

LOL

:D

Jan

Hi Glenn. You infer that the SVDA distributor is new. Is it? I suspect your problems are in the distributor - you DID put on all new wires, didn't you? How about the little spring that sits under the distributor shaft? What part of the world are you in nowadays? -BaH

yep it's new. And I did put on all new wires, thanks for asking. And the spring. remind me to tell you sometime about how I discovered how to remove a distributor drive shaft with a tap and die set. It makes the spring sit in the hole real tight afterwards, too, on the lip of the thread you create. But anyway, what I've found so far is, I took the compufire points out and put in stock, and changed coils to another one I had in the shop. I also adjusted the valves, but since most of the adjustments were to tighten, not loosen the gap, I don't think that was it. Tomorrow I'm going to put the compufire points back in, on the theory that the coil was the problem. I'll let you all know.

And by the way, I'm in Washington now, in Silver Creek. Not really close to too much, east of Centralia, if you know where that is. Working for another sawmill, actually, two. I do the programming and networking for the two mills. Loads of fun, in a workaholic gluttonous sort of way. We just built the second mill last year, and things are beginning to simmer down to a dull roar, enough that I can start to do things like live life, post messages to my favorite air-heads, and raise kids.

You guys must wear the teeth off them saws awfully fast! Still getting timber with ash? I grew up working in a sawmill. Dad was the sawyer... and everything else, I guess! Programming? Hmmmm. That would be whatever was going on in dad's brain at the moment. He had a Sherman Tank engine for power with a '29 LaSalle tranny but that kept getting ripped off, so he had to switch to chain drive reduction to the flat belt pulley - about a 12" flat belt about probably close to 30' long full loop. Had a length of twine - actually clothesline - for a throttle control and he ran the speed that "sounded right". It seems to me the saw was about 4' diameter. I remember seeing it buried quite a few times. Hmm how do I work VW content into this? Guess I'll just have to incur the wrath of those to whom it makes a significant difference. I might actually get to come meet you some day, being that close - just a warning! Hey - you're once again close to LaGrande - but in a different state! -BaH