3 problems on my 72 Beetle cropped up

[Marc]

viewtopic.php?f=18&t=127818

[rrb6699]

wow, thought maybe the forum went away. hey again. well, the problem still persists when I drive 20+minutes and stop say to run in the house maybe 5 minutes, then come back out and try to take off again. Last Sat it happened and I couldnt get started once I drove a block, pushed it home, drove other vehicle to a party, came back 3hrs later and it started. something is getting too hot. dont know what. maybe the whole engine.

next:
ive been running terrible lately at high speed (accellerating thru gears), so, I did take the carb off, cleaned all the parts, put it back with new intake gasket and wow, it idles perfect, doesnt stall. now its the acceleration problem. maybe it liked the extra air sucking in at higher rpms bit made idling impossible. now its the opposite. have adjusted the valves and noticed the TDC mark on the pulley wasnt lined up so I decided to line it up, set the rotor with it and adjust the valves.

well, when I started up I couldnt hold an idle so I moved the rotor and got a good idle again, but, sti cant get a smooth running enging at higher rpms, even moving the rotor and keeping it revved. I just set the rotor where I thought it sounds best, but, now do I have to redo my valves? it sounds like crap when im driving but great when it idles.

id rather have it the other way and am half tempted to remove the intake gasket and see if it runs better at driving speeds although im not sure why that would even affect it. its right below the butterflys.

right now im trying to lean it out from 1.5 turns out on the mixture screw to less and less, but, so far no difference.

the last thing I can think of is a compression issue somewhere but dont know how to find that yet.

any ideas appreciated.

[rrb6699]

rear view of my Weber two barrel 32 36DFAV 23 E6 carb. if this is a DFAV (says on the carb body) why is there an electrical spade plig? is this a modified electric instead of water choke?
in that case what hooks to this and how much voltage / current should there be and how does it work?

[rrb6699]

rear view of my Weber two barrel 32 36DFAV 23 E6 carb. if this is a DFAV (says on the carb body) why is there an electrical spade plig? is this a modified electric instead of water choke?
in that case what hooks to this and how much voltage / current should there be and how does it work?

the mixture screw is the bottom one and the idle screw is shown on the linkage. these are the only two adjustments on the carb. I have it running a little better now but still have some bucking if I accelerate too quickly thru the gears, if I accelerate slowly and gradually apply gas it seems to run better.

could it be too lean? I had the mixture screw 1.5 turns out but have been turning it back towards lean a little at a time. maybe around 1 turn out now. it hasnt made any difference that I can tell on the symptoms described here.

idle is nice and steady.

[Marc]

...noticed the TDC mark on the pulley wasnt lined up so I decided to line it up, set the rotor with it and adjust the valves.
well, when I started up I couldnt hold an idle so I moved the rotor and got a good idle again, but, still cant get a smooth running engine at higher rpms, even moving the rotor and keeping it revved. I just set the rotor where I thought it sounds best, but, now do I have to redo my valves?...

Hoo, boy, where to start?
Has nobody ever told you to NEVER set the timing on an engine "by ear"? The chances of you getting it right are almost nonexistent (even with years of experience it's still unlikely). 9 times out of 10 you'll end up with too much spark lead, which can knock the hell out of the ring lands in the pistons.
The 32/36 Weber, and its Holley & Motorcraft clones, are infamous for flat-spot problems. It's not so much a problem with the carb as with the physics involved with an oversized inlet tract when the carb's so far away from the heads - nearly all centermount 2-bbls suffer from this. When the manifold is kept warm it's not so bad, but with a cold manifold all bets are off, and pig-rich jetting may be needed to totally eliminate the hesitation. There are "deluxe" manifolds made for the progressive carb which provide much better heatriser action than the standard type, but with an aftermarket exhaust system even those don't guarantee relief - unlike a stock muffler, they don't provide a reliable flow of gases to the intake's preheat passages so the heat transfer pretty much comes from convection. You may be able to make it drive sweet on a warm sunny day and still find it horrid to live with when the weather's cool & humid.
Long story short, you're not the first person to have difficulty tuning out driveability problems with a proggy - that comes with the territory - but the ignition timing should never be used to try to mask the real issues.

Unlike most engines which drive the distributor off of the camshaft, the ACVW has separate gearsets on the crankshaft so they operate independently - camshaft timing has no effect on ignition timing and vice-versa. But regardless, valve LASH settings are not affected by timing changes.

The electric choke heating element is supposed to be receiving 12V power from the ignition switch (off the +/Term 15 post of the coil). This circuit has no fuse protection from the factory so a short could fry the wire all through the harness, and perhaps a few of its neighbors. Some folks like to add an inline fuseholder up front to protect against this. I mention it because when you make up a wire from Term 15 to the choke heater you want to route it so it won't get its insulation damaged and short the circuit - and use wire that's smaller-gauge than the supply wire so if a short does occur it'll burn out before the supply wire does.

It's been a while; did I ever ask you what distributor you have? The 10-digit Bosch number is the best way to identify them.

[rrb6699]

now this car ran like a bat before. it just had problems setting idle. too fast, too slow, etc. had to set it low to save fuel and it did. I found out the intake gasket was leaking in 2 spots so I replaced it and cleaned out the carb. wow. I started it and it just idled perfect. I couldnt have tried to set it that well. but, the test drive had really rough flat spots, bucking, etc. this before I messed with timing. so how do you set timing properly? what amp fuse should I use from positive coil to the carb?

It may be the way you say about setting timing by ear but I could hear where it ran best in idle and acceleration.

it can th be that far off. im wondering why my timing mark doesnt correspond to the rotor pointing to #1 TDC in the first place. I also marked where it was before moving it and it pretty much settled back to where it was originally. if I move the rotor to be lined up center in contact with #1 wire, the timing mark movess past the seam quite a bit. ( talking about counterclockwise turns on crank pulley not physically turning the rotor).

I only set the valves because you have to line all this up to each timing mark for it to fire at the right time for each cylinder correct?

is this way more complicated because I want to do it right.

I can drive it as long as I gradually give gas slowly and steady at each gear shift but even that doesn't guarantee it's not going to Buck especially in 3rd gear.

If it does I push the clutch in, give it a rev, and try again and eventually I can get it to smooth out.

I know this carburetor can run this car perfectly because it has before. At least until I sealed all the air leaks.

now how to get it back. I'm half tempted to take the intake gasket off again and try it as an experiment.

[Marc]

...what amp fuse should I use from positive coil to the carb?...

That's NOT what I said. If you want to protect the coil feed wire in the harness, put a fuse up front where it connects to the wire from the ignition switch. Normally an 8A won't blow, but I'd use at least a 15A...that'll still pop if there's a dead short without much chance of it doing so under normal operation (even when the backup lamps are on - their power source originates with this wire too).

A fuse in the wire from the coil to the carb would still leave a wire (from the coil to the fuseholder) which could cause trouble if it shorted. Just use a wire that's smaller than the one TO the coil and in the event of a short it should self-sacrifice before the feed wire is damaged.

[Marc]

...It may be the way you say about setting timing by ear but I could hear where it ran best in idle and acceleration...it can't be that far off...

How much would you like to wager? I'll cover that action ...where it "runs best" is nearly always too far advanced. To set the timing properly I need to know what distributor you have.

Except in the case of a radical camshaft with lo-o-ong clearance ramps, the lifters are "on the base circle" (where they need to be for adjusting valve lash) if the crankshaft is anywhere close to the appropriate 0° or 180° position - it's not really critical.

The notch on the rim of the distributor housing is not for use in timing - it's just a reference point so you know where to place #1 plug wire...timing should be set in reference to the crankshaft pulley markings.

As I said above, the cam and distributor are independently driven. If the distributor drive gear is installed incorrectly the rotor may point somewhere besides the "normal" (~4:00) spot when the crank is at TDC ready to fire #1...that can lead to physical interference with the vacuum canister and/or condenser that prevents rotating the distributor enough to set the timing correctly. On most later-model distributors you can get away with simply installing the wires 90° or 180° "off" to compensate, so the distributor ends up in a normal position, but the rotor points towards the notch for some cylinder other than #1. Until the `70s, VW distributors usually had 2-3° of retard built in for #3 cylinder so it's not permissible to pull this trick on those ones, making the installed position of the drive gear more critical with them. But in any case, the notch on the distributor is just a gross reference point, not a precise timing mark.

[SCOTTRODS]

Last Time I set my Timing "by ear" (Which was the first VW I owned)... It burned a hole in #3 Piston from being too far advanced... I've owned about 23 other VW's since then and NONE of them were set by ear after that one. Cost too much time to do that kind of stuff... Back then a set of P&C was 100 bucks everywhere, and my paychecks weren't much more... So even at 100 bucks, it sucked. I sure wish I could get Mahles for that now...

[rrb6699]

ok,
just had to get it running better, even if its not right it drives "ok". I just figure this to be a carb issue too. something changed when I cleaned the carb and put new intake gasket on it.

ok, so this is very interesting to me about the cam and distrubuter beibg independently driven.

please remember this car was running great for a year before all this. I know what you are saying about weber carb issues, but, had it never ran well I would have no choice but to agree that ill have to live with flat spots, etc. when the car had a Solex on it there was a huge hesitation on acceleration. thats why I opted for the Weber.

the unit I have on this Bug is electronic. the previous owner changed out the points. I can't see any name on it. perhaps its a Pertronix Ignitor with distributor. the plug wires are 8mm and look like the ones that come with the Compufire unit but I bought them separate.

ok, as for the notches on the pulley, I still use the notch and the seam? that sounds like my problem. I was using the rotor to point it to the #1 wire irregardless of the pulley mark.

so since I marked it, I'm assuming I got the rotor back to its position before I moved it.

I should ONLY go by the pulley marks and just close the rotor cap once I know which points to #1 TDC correct?
Then redo the valves based on that. it seems to me the valves should be off right now am I right?

as for the fuse-- wouldn't or shouldn't the wire from the coil to the fuseholder already be fused? seems to me everything should run thru the fuse panel.

[Piledriver]

as for the fuse-- wouldn't or shouldn't the wire from the coil to the fuseholder already be fused? seems to me everything should run thru the fuse panel.

See sticky "10 things that result in death and destruction"
http://www.shoptalkforums.com/viewtopic ... 1&t=126942

All were learned the hard way by someone.
Learn from their pain.

[Marc]

(1)...the unit I have on this Bug is electronic. the previous owner changed out the points. I can't see any name on it. perhaps its a Pertronix Ignitor with distributor....

(2)...I should ONLY go by the pulley marks and just close the rotor cap once I know which points to #1 TDC correct?
Then redo the valves based on that. it seems to me the valves should be off right now am I right?...

(3)...wouldn't or shouldn't the wire from the coil to the fuseholder already be fused? seems to me everything should run thru the fuse panel.

(1) All stock VW distributors have some identification markings, most are stamped into the side of the housing (may be on the "back" side and not visible in the installed position). If it's an aftermarket unit things can get even more complicated - for example, Pertronix makes three different distributors for ACVWs that I can think of, and they each have their own ideal initial timing. Look again for any stamped-in numbers; if there's nothing there, post a picture so we can try to figure it out.

(2) One more time....set the timing using the crank pulley markings. Changing the ignition timing will have ZERO effect on the valve lash, true of any engine - not just ACVWs.

(3) Perhaps the wire feeding the coil should be fused, but the factory chose not to (trust me, I'm not making this stuff up). The wire to the coil comes from the ignition switch side of the fusepanel, upstream of any fuses.

[rrb6699]

oh wow. now I see what you mean about that not being fused between those two points. usually, I find the mfr had a reason for the way they design certain things. I guess I got that from working on boats where everything is designed for a reason. I learned the hard way just changing seemingly minor things on my first boat restoration.

it is an aftermarket distributor. see pic. however, I have to say I set the pulley to TDC, set the valves properly from that point and its running like a charm. no flat spots just a little rough the first three tenths of a mile and it has power and is smooth thru all the gears. I still want to know about the distributor and why my "logic" on the valves seemed to work.

at first when I listened and it seemed like the valves had some tapping going on but it wasnt in any pattern. then upon closer listening I discovered these were occasional "gentle" backfires for lack of a better description.

maybe a tad leaner on the carb and ill have it set. that was also the other thing I did. I leaned out the carburetor from 1.5 turns out to about 1 although it could be plus or minus some since I couldnt count how much I turned it because I had to grab the mix screw with needlenose and give it as much a turn as it would allow which was probably 1/8 - 1/4 a turn at a time and a couple tries it wasnt turning it. thats why its hard to estimate.

now that its running maybe I can get on to completing the restoration.

see attached pic.

vwDistributorPic.jpeg

[rrb6699]

hey all,

I've still got a decent running machine with good power, no hesitation thru the gears. on idle theres an occasional "gentle backfire" that sounds like a valve tap, but, it doesn't occur in any noise pattern so I figure its either a tad rich or just slightly off time. the noise disappears when I apply throttle or drive.

Anyway, the heat issue still bothers me because I haven't been able to try a different coil. it hasnt died on me after a long run, stopping then starting but the weather's been cooler until today. I ran errands and did several short (like grocery) stops then come out and take off. only once did it seem like it was having an issue, but, it kept on going. so, I still think the problem remains. I think it may be the coil getting overheated. ??

is there.... or what is the best coil to go with. I can only speak from my original Bosch that was on the Bug when I got it and the Blue coil you see in my pics I bought from MaMotoworks. Dont have the name, its been awhile. I think its rated 45k volts or something along those lines. I'm using cool plugs not hot fire. I was thinking of getting a bigger sump to see if that helps with cooling.

Do the make hi-temp or harsh condition coils I could use?

also, I noticed a little smoke coming out of the oil blowby and filler cap after I drive (remove the cap). I would think that's not normal but, I don't know all the ins & outs of these things.

tia,

[SCOTTRODS]

Have you ever just taken the engine out and cleaned it? The amazing thing about these air cooled engines... they get dirty... It inhibits the cooling capabilities... Sometimes Animals build nests (Wasps, Dirt Dobbers etc...) and limit cooling air flow as well. Tearing it down for a good cleaning is a good way to understand and familiarize yourself with the engine and "it's ways". A Clean engine is a better cooling engine at any rate.

You may have already done this, but this suggestion isn't a "willie nillie" suggestion... I've lived the dirty engine heat problem before. The struggles you have are real and not uncommon. Sometimes things are very simple...

Also your minor "back fire" can be something simple like a little hot spot in the muffler that you will never see... A little "tag" of metal that gets hotter than normal due to it's shape, will ignite the un-burned fuel in your exhaust stream... This is most apparent at idle, or when decelerating under load (engine breaking)