Hello,
I am new to the site and have a question regarding poor acceleration from my 73 super beetle auto stick. In a nutshell the problem is this. The car seems to run fine and accelerate fine when you are traveling, but when the car comes to a stop at an intersection it bogs down and has poor acceleration, it sounds almost like it is flooding with too much gas. If I ease up on the throttle and feather the pedal slightly it improves and then once up to speed again runs fine. What could be causing this?
here are the particlulars on engine carb and dist combo:
1. Engine is new Puebla VW plant Stock 1600 dual port (no id number printed on case below the alt stand)purchased on business trip in Mexico back in 2001 at the VW Puebla plant
2. Carb is new Bocar pict 34 carb also purchased new in Mexico in 2001
3. Dist is the original equipment vacuum advance distributer from 1973
here is what I have fiddled with so far to try to solve the problem:
1. engine timing. set engine timing (v mark on original crank pulley) to line up with case seam. Was set by previous mechanic slightly to the left of the case seam probably 7.5 deg BTDC. Now set at TDC. the result was that engine idles very smoothly now no shaking or stumbling what so ever
2. Fuel system. car was in storage since 2003. prior to putting it back on the road I removed the carb and cleaned every nook and crany out with card cleaner. Carb now looks like new. Car had bearly no gas in the tank at the time of storge. I have now run about 4 tanks of superunleaded through the car
3. Airfilter replaced and stock air filter housing completely dis assembled and cleaned (lots of soot inside)
4. Distributer cap and rotor changed and inside of distributer was cleaned out (had some greasey stuff inside) inside distrubuter was then sprayed thouroughly with electrical contact cleaner till clean.
Hopefully someone here will be able to help me. Right now I think that the problem is with the distributer. Most probably the vacuum advance but not sure.
Also if anyone can provide me with the tuning specifications for this car I would be very greatfull as I would love to see her run again exactly the same way as when I bought her from Jerome Avenue VW in the Bronx back in the spring of 1973.
Thanks,
Steve
Steve,
G'day and welcome to the slowly expanding membership (you missed out on the old board)!
I have some questions and you can dig up some info along the way for posting back.
1. With the new Mexi motor, did you re-use your old pulley?
2. That Bocar, does it have the correct CV feed port?
3. Read all the numbers off the distributor and post them back here and also check for yourself at www.oldvolkshome.com in the Bosch distributor page.
My question about the pulley has to do with timing marks. They changed over the years and I've found it better to physically measure where TDC actually is, and mark the pulley. A quality degree pulley eliminates guesstimates.
With that Bocar, I'd pull it apart and spray all passages with carb cleaner and blow compressed air through everything. Also check the condition of the o-rings around the volume and bypass screws. As far as the CV feed goes, if it hasn't got one then make one. Have you still got the old carb?
I'll have a look later at my Bentley, but you should also check that your rotor is free to advance. When it's in the car, remove the cap and try and turn the rotor either way. It should move in one direction only and smoothly at that. If there is a felt wick under the rotor, put some droplets of engine oil on this. Your points block/distributor cam should have a small amount of grease (Bosch lube) on it too.
Adjusting the 34 Pict 3 is finicky, so go to http://www.vw-resource.com/34pict3.html for adjustment procedure.
When it's all said and done, you should check timing and advance with a timing light.
Bet you wished you never asked ;D
Volkenstein
Volkenstien,
In response to your questions:
1) The pulley is o.g. to the car, it has only 1 v mark in the pulley. I have seen pulleys with more than one mark before, they have a v mark and a semicircular mark about 1/2 inch to the left of the v mark. I was told the v was TDC and the semicircular mark was the timing mark. Is that correct?
2) CV port? I am not sure please explain? Right now the dist I have has a circular disc on the side with a metal tube that connects to the carb on the left side next to the idle adjustment screws in the main throttle body. there is also one other port on the back of the carb on the bottom left(closest to the fan shroud) which has no connection to it.
3) Dist # 0231170036 The web site you referred me to says it is a 1974 model.
For the record I am very glad I asked and very glad you responded, I really want to learn how to fix everything on this car myself. Its the first car I ever bought and I want it to run forever!
Thanks,
Steve
Steve,
It's the other way around. The semicircular notch is TDC, the "v" is for timing. Does your pulley look like this:
(http://i40.photobucket.com/albums/e210/ctefeh/MISC/Pulley.jpg)
I've greyed where the semicircular notch is. The 'v' is at 7.5 BTDC.
According to my Bentley, Spring 1973 and newer cars having your distributor have a single 'v' notch, means it's @ 7.5 BTDC. So your all set!
OK. On Autostick carbs (for 1600 TP engines) there are three or four pipe connections on the carb. Like so :
(http://i40.photobucket.com/albums/e210/ctefeh/MISC/CarbVac.jpg)
You have just opened the deck lid and are looking at the carb. The yellow highlighted spigot is for vacuum advance, The blue highlighted one is for vacuum retard for a DVDA distributor and the Red one is for the CV (Control Valve) feed.
You may or may not have a fourth connection which is facing up at you on on the right of the carb about a 45 degree angle very close to the throttle shaft.
Manual carbs do not have a vacuum spigot for the CV, Autostick's need one. Have a look at your CV and you should count 3 large bore cloth braided hoses. Close to the firewall there should be one small diameter hose coming of the large casting, between the last large bore hose connection and the air filter which is closest to the firewall.
That hose connects to the Red spigot in my picture. If to your horror you find the Bocar doesn't have the CV spigot :o, just look at the 34 Pict 3 topic (first one by Eddie) and "how to" is explained in there
The distributor you have is coined as an SVDA. Single Vacuum Dual Advance. This means that the Vacuum retard port on your carb (Blue in the pic) should be capped off. So you've been to Oldvolkshome and found your dissy so you know it should be 7.5 BTDC at 950 +/- 50 Revs, vac hose off and plugged.
Grab a timing light and go for it ;D Once it's set and you've tightened the clamp, rev the car while still holding the timing light. The 'v' notch should move around 1 3/4 inches to your left. That'll tell whther the mechanical advance is working. Connecting up the vacuum hose should give you up to an extra 1/2 inch of movement.
Enjoy
Volkenstein