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Hey, thanks for responding to my long long email. Unfortunately, it gets longer and I can use all the help I can get.. First the story: 72, dual carbs. So last night I get into my car and start it up. Now, I had timed it statically at 0¡, which according to Muir was the notch furthest to the left, ok? Started it up, it was shaking like mad. Gave it a steady stream of light warm-up throttle, still shook when I let the gas off. Dammmit! So I turned off the ignition, and decided to advance the timing to the second notch. Still shook. Third notch. Still shook. Last notch, not bad but not great. Then just a *hair* over. Perfect. Smooth, beautiful idle. Good power but not racing, very nice. Suspiciously nice. I just don't get it. It HAS to be advanced too far. Still I'm living with it for the next few days until I get this solved. Went home and looked at Bentley again, and thought well, maybe that 2nd chart is right, which would make the 4th mark 7.5 BTDC, which is what Keith recommended. Still I dont know if Keith was talking about using a strobe. Also, re-reading Bentley I noticed it says something Muir doesn't: pull off the hose to the vacuum adv. diaphargm unit. When I did my timing the hose was connected. Does it matter that much for statictiming? Does it matter at all? <<Yes, it's a strange arrangement, but once you realize what the right way to do it must be, it can be done rather easily with a 10mm wrench stuck down between that shaft and the fan housing.. Don't feel too bad, on my first encounter with this dilemma in around 1970 I spent days trying to figure out what VW intended me to do.>> OK BUT, my nut goes UNDER that shaft where I cant get it completely tight. A bit frustrating. If you have a good used clamp cheap, I want it. Tell me how much. Give me your address. Maybe I'll pull out my speedometer while I'm at it (but dont hold your breath) >> Pulled out distrib. loked at shaft. Engine was at TDC 0¡. Drive shaft >>was at an angle, but not quite as extreme as that shown in Bentley. >The angle shown in all the books is not quite right, but it is close. Was >your drive shaft groove offset in the correct direction? If the angle was close and the offset was correct, then your drive gear is installed correctly. This is good news.< This IS good news. Offset is correct. Whew. Now I dont have to do that coat hanger thing. >It's not clear to me what you mean here. By "vacuum plate" are you >referring to the vacuum advance diaphram unit? If so, distributors up to 71 have the cap mounted just CW from where the green points wire exits the dist body, 72 and on mount the cap slightly furthur CW, from the CCW-most of the two mounting bolts for the vacuum unit. There is no real difference, except that the later version gives more room for your 10mm wrench to adjust the timing.< Yes. Vacuum advance diaphragm unit.Sorry about the poor use of the technical terms.. On my distributor, the points wire exits straight out the rear of the distributor (using rear as rear of car, front is front) The cap of the distributor has clamps on the dead left and dead right. No offset whatsoever. Just CCW from the left clamp is the condenser. At dead front is the vac advance diaphragm unit. On this unit goes a hose that runs to the carburetors, which I'm afraid of for the time being (I'm afraid of the carbs, not the hose). >Your dist sounds like it is 180 off. Is it a FI dist (does it have the >extra trigger points in the bottom?) Regardless, it could be rebuilt and turned around. Without disassembling it I can't tell you exactly what has been done wrong, if anything.< A friend told me I cold remove the spring at the bottom of the distributor and remove the shim pin that runs through the driving dog, then flip the driving dog around. I tried that, but the shim wouldn't come out. I even tapped at it a bit using a punch. No luck. Yes I put the spring back on. Re: trigger point in the bottom. Bottom inside the distributor? What do they look like? >>I also looked through all the VW listings and the Porsche listings just >>to make sure it wasn't a 914 dist, but I've come up empty. What's the complete number? What's the OE number (stamped just under the Bosch number?)< Uh oh. Maybe I was wrong. I said it was an "040" because thats the number thats been stamped inside an oval on the top of my distributor cap. Also on the top of the cap, stamped between wire 4 and 3 is the number 1235522056, but this isn't the OE number is it? What does OE stand for? Stamped in the dist. itself, close to the bottom under the dist. wire is a number "022 905 205 S" There's also some numbers stamped on the distrib over on the left under the condenser and cap clip, but I can't see them and it's too late at night to pull my distrib. out again. Let me know if I should. >On the 72-3 version, I THINK the next to left notch is TDC. On this >version I THINK the notches are -5, 0, 5, 7.5. There is plenty of confusion on this question.< Gotcha. I think I'm going with the -5, 0, 5, 7.5 assumption. It looks closer to the ridiculously small and badly drawn diagram in Bentley. And how do you guys time your engines if there's confusion about where TDC is? How do you check valves? >Your dwell should be ~45-50 deg. Changing the dwell changes the timing so >you have to do the dwell first, then set the timing. This is true no matter how you go about setting the timing (timing light or static.)< Woops, sorry. I should have mentioned that I used an 8 cylinder tach/dwell meter. Muir says 25 + or - 1 is ok using an 8 cylinder tach/dwell meter. But I'll open the points to bring it down to 50. I hope I dont get a lot of email about this one. (oh yeah, I'll check the timing again too once I get the dwell between 45 - 50) The gap is dead-on .016", I can guarantee you that. I'm REALLY meticulous about this kind of thing. Following Bentley, I cleaned off my feeler guage really well using alcohol before I did it. >What do you mean "crankcase says 73"? Or is this just what you have >determined from the engine number stamped in the case.< Theres a big "VW 73" stamped on the crankcase. I saw it when I was visiting Keith Park, but I can't find it now. Strange. However, stamped to the cranckcase , under the car is the number 113 301 109 L Could this be right? The number is just to the front of the big roundy thing in the middle underneath the car sort of towards the center (front-to-back), stamped on the right side. >Is it possible that the thermostat has been removed from this engine? This >would make all of these things even worse.< Yes, how'd you know? That's on my list before summer ends Keith told me to get one. I was just doing one thing at a time. Maybe I ws doing them in the wrong order. Who should I get a thermostat from? I have to look at the manual more about this. I dont even remember where it's suposed to go or what it does. >>Carbs require a different vacuum unit, and you probably don't have the >>right one. There may not BE a right one, depending on which dual carbs you have. Is there even a place to connect the vac adv on these carbs?<< I have Weber Carbs, on the advice of the guy who rebuilt my engine. I've since learned that Webers are bad. But he's a good mechanic with a good reputation in NYC. He ran a Beetle Shop for years! And he's a great guy. So way back when, before I found the link, how was I to know? (Oops, sorry, I'm getting a little defensive - I just feel so stupid.) Anyway, the Vac Advance IS hooked up to a hose which connects to T-connected hoses that run to the carbs.... > if your plugs are black, it is possible that your dual carb setup is just >running over rich and dumping a lot of extra gas in your cylinders. This >will result in gas diluting the oil in the case and increasing the >apparent oil level that you read. It also washes down the cylinder walls, >removing the oil film that lubricates the rings and causes rapid cylinder >wear.< Yes I suspect that's true, and I dont want it that way. I need to learn how to fix this. >You should probably forget about the fact that your car is a 72. The >stock tune-up specs for a 72 are useless to you since your engine is no >longer stock. What you need to do is find out what the best way to tune >an engine like yours should be. This is not an easy task and depends on a >lot of factors. < You're right about this. I just dont know what the factors are, and I dont know alot about my car, or cars in general. My girlfriend keeps saying "Why did you mess with it in the first place, it was running fine?" I suppose she's right, but what worried me was that there was no way I could KNOW that it was running fine but that somewhere down the road I'd blow a cylinder or something. I had no way of knowing if the mechanic really did a good job. And I had no way of explaining why the car acted like it did on occasion, somedays with no power, or pinging, etc. By the way, I haven't heard a ping in a while. I think the gas station I was going to was selling lower octane gas than it said. Who knows.As you can see, there's alot to do. Please be patient with me. I'm a fast learner. Thus continues the series of questions caused by just trying to do a tune-up. Newcomer take note. If you have just purchased a T3 you have just added another member to your family. If lots of work doesnt appeal to you, I recommend a nice looking plant or a cat. I myself like the work. Everytime I get in the car it feels good. -mike ------------------------------------------------------------------- List info at http://www.vwtype3.org/list or mailto:help@vwtype3.org