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BrettBrokaw Fri Apr 27, 2012 5:17 pm

Quick summary i have a 73 super beetle that runs great, that is until about 3 days ago. Ive looked up possible solutions but with no success. My car will start (rough a little bit for the first 2 minutes. also need to tap the pedal a few times to keep the car alive), once the car is pretty warm it can idle on its own without needing the gas. Its a bit rough but runs. When i start to leave the car will accelerate but then it randomly stops accelerating and if i try to give it gas it will get worse and then pop really loud. if i back off and give it a second i can accelerate a bit more until it acts up again. ive tried letting the car warm up longer, timing to factory specs, checked spark plugs/wires, checked distributor, etc.
Im at a loss at the moment and will most likely take it to my specialist in a few days.
any advise would be greatly appreciated. I can provide pictures and more info to help give possible solutions. Thank you.

Relyt Fri Apr 27, 2012 5:23 pm

Have you adjusted the valves?

http://www.vw-resource.com/valveadj.html

Valves out of adjustment will cause you all sorts of problems like this.

BrettBrokaw Fri Apr 27, 2012 5:29 pm

I've attempted to see what the gap is on them but i cant even get the cover off lol
I removed the two side bolts and for whatever reason the cover doesnt want to budge.
I was planning on checking them to time the car

Relyt Fri Apr 27, 2012 5:35 pm

There shouldn't be bolts holding them on, unless you got some sort of after market thing going on.

There should be a large bail wire clip that you pop off with a screw driver.

BrettBrokaw Fri Apr 27, 2012 5:38 pm

Yeah I wish I had that right about now lol
Im not sure when it was replaced but thats all there is, is 2 bolts and it just sits on there. I can get pictures if it would help out. and thank you for the quick response, i've been scratching my head on this for a bit

Relyt Fri Apr 27, 2012 5:47 pm

I have no experience with the after market bolt-ons, so I don't want to give you advice that may damage something, especially if this is a daily driver. So with that disclaimer:

Who knows, maybe the PO put RTV on both sides of the gasket, you can try to pull or pry it off, just try not to damage the cover or the mating surface.

If you do successfully get them off remember to do everything according to the directions and make sure the car has been sitting overnight first, so it's completely cold.

It may seem complicated at first but it's super easy after a couple times.

BrettBrokaw Fri Apr 27, 2012 5:52 pm

yeah, Im not affriad to mess with something like that, just wish it was a bit easier to pop that off.
Its my daily driver but tomorrow ill have another car to drive till this is fixed.
Ill try again here in a second.
is there any other reason i would be losing acceleration and popping?
it will occasionally even die unless i leave the car alone and dont touch the gas. I figured air/fuel mixture but I just had the carb put on and tuned about the end of 2011

Relyt Fri Apr 27, 2012 6:58 pm

It could be fuel air mixture.
It could be something clogged in the carburetor.
It could be a vacuum leak.
It could be a distributor/timing issue.
It could be a fuel pressure/blockage issue.

But if you want more specific answers you'll need to provide more specific information.

What make and type is the carb?
What make and type is the distributor?
Did these problems just start, or have they been getting worse?
Did it run "perfect" after the carb swap?
What's your dwell?
What's your idle rpm?
Do you have your stock air cleaner?

But my gut reaction would be valves, popping is caused by gas combustion in the exhaust system, tight valves would cause this, or way off timing. And valve adjustment is the basis off every other tune up procedure.

You can check for vacuum leaks by spraying carb cleaner (at full warm up) around trouble spots (manifold boots, throttleshaft bushings, where the carb meets the manifold, where the manifold meets the head) and see if the idle changes. You can also remove the air cleaner and slowly block the air flow into the carb, if it idles better then either you're running lean or you have a vacuum leak.

Make sure your vacuum and fuel lines are in good order.

And don't forget to change out the fuel filter, a dirty clogged filter can cause problems.

BrettBrokaw Fri Apr 27, 2012 7:25 pm

ok, so i just got back from fixing the gap on the valves. I had to use a hammer and a folded towel to loosen the covers. Cylinders 2, 3, and 4 were too tight for a .006" blade to run through. I adjusted them all and the car seems to run smooth, but i dont want to get my hopes up just yet.
I know the carb is a Weber. but not sure what model and same for the distributor.
The problem just started 3 days ago and since then have gotten a little worse.
Im not sure what the dwell is and i couldnt say what the rpm is at because i dont have a guage. I set the timing to 5 after TDC but it made it a bit worse so its back at 10 after TDC which is where it was set after the shop fixed the bug.
Ill try to post an image to give you an idea of the engine.

BrettBrokaw Fri Apr 27, 2012 7:27 pm

Heres the engine right after the shop.

[/img]

Relyt Fri Apr 27, 2012 8:07 pm

That looks to be a pretty sweet setup.

The distributor looks like it has a number stamped on the bottom there, see if it has the make and number, with that number we can find out the proper timing and advancement for you (although you probably have it right on as it shouldn't have changed since the shop did it). And I'm assuming you mean before top dead center, as it wouldn't run otherwise :P .

Time for me to be honest, Webbers are out of my league, I deal with stock. I hear their a pain to deal with (but awesome when they are tuned right, and it sounds like it was).

So the only advise I can give is:

1) Trace the fuel line to find the filter (usually under the gas tank up front or by the transmission in back, or both) and change it out just to eliminate that possible problem.

2) Take it out for a spin and see how she handles, go up a couple hills.

3) If it still has problems wait for someone more knowledgeable then me, especially with your setup, to chime in.

Your engine bay is is immaculate and everything is in order, good job!

BrettBrokaw Fri Apr 27, 2012 8:26 pm

hahaha thanks. well im not sure what company made the distributor but its a 009.

I looked at the manual that came with the car and it says to time it 5 after TDC. any lower than that and the car struggles to stay running. Right now its at 10 after while idling.

I know Webers are a pain and ive experienced that from the last one that was on it. Thats why this one was put on to replace the old weber. I havent had any issues with it at all (assuming that it isnt causing the car to act up like that).

I would just swap fuel filters but i dont have the clear one with the filter in it anymore. The guys at the shop took that off completely and now the copper pipe leads to a short rubber hose and to the Fuel pressure regulator (I assume). If you look in the picture the pipe leads just behind the distributor, then rubber hose, and the regulator right in the middle.
Is that something that should be fixed? i thought it would be fine since an actual old VW shop set it up that way.

Thanks for all the help. if anything, at least the valves are set now lol

Relyt Fri Apr 27, 2012 8:50 pm

Glenn may chime in with the proper distributor for your carb.

Your car must have originaly came with a dual vacuum advanced (as mine did too). Those distributors are timed 5 degrees after TDC (to the left on the pulley).

The 009 needs to be timed at full advance (around 3000 rpms) at about 28-30 before TDC (to the right).

http://www.vw-resource.com/tune-up.html#svda

I just got one of those degree pulleys, makes life so much easier

And when you say regulator I assume you're talking about the fuel pump. You should have a filter, most people move theirs out of the engine bay to prevent fires (a hose can slip off and dump fuel all over a sparking distributer). Hopefully your shop did just that, so check the two places I suggested. If you can't find one I would suspect crap got into the carb due to unfiltered fuel.

ashman40 Fri Apr 27, 2012 8:52 pm

BrettBrokaw wrote: ok, so i just got back from fixing the gap on the valves. I had to use a hammer and a folded towel to loosen the covers. Cylinders 2, 3, and 4 were too tight for a .006" blade to run through. I adjusted them all and the car seems to run smooth, but i dont want to get my hopes up just yet.
Did you adjust the engine "stone cold"? If you fired the engine and got it running at all... you should let your engine cool down for a few hours before attempting to adjust valves. The warmed up engine will change the valve gaps. Ideally, once the engine is fully warmed up, the valve gap would close to almost zero. So setting the stock .006" gap on a warm engine means it will be a larger gap when it is "stone cold".
Valves should be adjusted 1st thing in the day BEFORE the engine is started.

BrettBrokaw wrote: Im not sure what the dwell is and i couldnt say what the rpm is at because i dont have a guage. I set the timing to 5 after TDC but it made it a bit worse so its back at 10 after TDC which is where it was set after the shop fixed the bug.
Ill try to post an image to give you an idea of the engine.
<...>
I looked at the manual that came with the car and it says to time it 5 after TDC. any lower than that and the car struggles to stay running. Right now its at 10 after while idling.
Your original VW manual has the settings for the original engine as it came from the factory. Obviously, you have a different carb and distributor. You cannot assume the ignition timing values will be the same... they aren't.

When you say you set it to 5ATDC or 10ATDC are you aligning the case split with the marks to the left (counter clockwise) from the TDC mark on the degreed pulley?? ATDC marks are left of the TDC mark. BTDC marks are to the right.
The crank is rotating clockwise. If the spark fires and the TDC mark has not yet made it to the top of the rotation... the spark fire BEFORE TDC. If the TDC mark has already rotated PAST the case split, then the spark is firing AFTER TDC.
So with this understanding, is you timing now set at 10BTDC (markings to the right/cw of the TDC mark)? This is probably okay for a 009. Ideally you want to follow these steps to set timing for the 009 to make sure it is not OVER advancing at max advance:
http://www.vw-resource.com/009_dizzy.html


EDIT: Relyt was a bit faster responding than I :(

BrettBrokaw Fri Apr 27, 2012 9:33 pm

ok, i got confused with the before and after as the numbers are all positive. Its 10 Before TDC.

Yeah it was sitting for most the day before i touched it. ill head out early to make sure its still set for .006".

I just took it for a quick test drive around the block and up/down this hill nearby. Its still acting up, but doesnt pop as much. hardly made it to the hill (heading down the hill).

Would it be blockage somewhere since it happened out of nowhere? its gotta be something similar since it was perfectly fine one day and nearly undrivable the following morning.

BrettBrokaw Fri Apr 27, 2012 9:54 pm

So reading into the 009 distributor and it mentioned the "flat spot" and linked to another page talking about hesitation. It had some relative problems and i was thinking that maybe the list of possible solutions at the bottom of the page might help.

http://www.vw-resource.com/hestate4.html#009

I had the bug running for a long time since the new carb so i dont think its a mismatch and also i havent messed with it so i dont think its incorrectly adjusted. maybe just an air leak in the intake manifold or clogged fuel filter?

Ill look for that filter in the morning, it has to be somewhere

dan macmillan Sat Apr 28, 2012 4:38 am

Does it run better if you slowly open the throttle and get worse the faster you open it such as when passing someone? If so, have a look at your accelertor pump. Make sure you are getting a steady spray from the accel pump nozzles as you open the throttle, {engine off, looking inside the carb throats}.

BrettBrokaw Sat Apr 28, 2012 7:12 am

At first it would run slightly better when i baby it, but the past day or so it hasnt mattered what i do. usually when it hesitates to accelerate i take my foot off the gas immediately, then roll along for a second till it sounds like its better, then ill very slowly push on the gas. This helped avoid the loud pop but not the hesitation.

Ill give it a go again today, but ill probably end up leaving it at my wife's uncle's as he is a mechanic and has a few possible ideas.

bajagunny Sat Apr 28, 2012 8:12 am

that carb will perform great but all it takes is a speck of dirt and it will cause trouble
check you idle jets they are just below the fuel inlet
there are two of them
make sure when you take the holder out tha you dont loose the oring

clear out the jet with a thin piece of wire and use some carb cleaner or brake cleaner
reinstall them and see if that helps

almost all of your driving is done on these jets
you might want to look into getting some jet doctors
they are tubes that are installed into the air feed orifice for these jets and help keep dirt form getting in there

BrettBrokaw Sat Apr 28, 2012 10:04 am

Well, ill have to look into it a bit as i am unaware of what to mess with lol
I have the weber tuning kit with the various jets and stuff. I read that I should have a larger main jet because of my Bosch 009 distributor.
if thats so, how would i go about changing that? The VW resource site said to use a 130< and the smallest i have is 145.

Update: This morning i went out to recheck everything i've done so far. This time with the help of my tester light.
I had the light set up the whole time i checked the valve gaps (they were all .006" where i set them last night except 1-2 valves were a little loose, so i tightened them.)
I looked at the distributor and cleaned the rotor arm and the contacts in the cap. Tested the gap of the points and its now set to .016".
I cant check the dwell cause i dont have the Tachometer.
Lastly i have found the fuel filter just behind the engine bay by the transmission.
Its the small tiny filter but I have a bigger, new one i can exchange it with.
There was a little debris inside (small paper thing like substance that sits at the bottom of the filter. otherwise it looks very clean.
Would it be ok to switch to the bigger fuel filter?



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