frankly, I'm not getting any progress on my bug's 'bad running' issue. So far;
I've changed the carb from 31PICT-4 in a 31PICT-3. Adjusted it by ear. It ran better but still died after the choke has disengaged
I've checked leakage from the manifold by spraying carb cleaner near the booths and gaskeds, no change. I even tightend the manifold on the heads..
When the car dies, it keeps on running pretty normal after restarting it. Could this be a clue?
Now I've noticed a golden/yellow residue on the left side of the carb (where the needles are) feeling greasy, and smelling like fuel. It is also sprayed all over the decklid by the fanbelt... Could this be related to the 'bad running' issue? Also when the engine is at running temp it still runs rough or/and wants to die. Before it only did that when cold.
PLEASE, can anyone point me to the right direction or even better tell me what's going on?? I've ran out of options :(
First off, you can't really adjust any carburetor until the engine is at normal operating temp, choke fully open, with the air cleaner in place. You can tweak all you want to keep it running when you first start it up after a repair but to do the procedure as it was intended the car must be warmed and choke open.
Having said that, have you checked the idle cutoff solenoid? Does it click when you touch the 12 volt connection to it? A failed solenoid will allow you to keep the engine running if you have the throttle open but at idle it will die.
How about your ignition timing, is it set correctly?
What about the endplay on your crankshaft, is it moving a quarter inch when you push the fan belt pulley back and forth? Besides tearing up your front main bearing and making the main oil seal leak, excessive endplay also causes your ignition timing to jump all over the place.
Are your valves set correctly?
What does a vacuum gauge read when the thing is running with the choke on, and what is the needle doing? If you can keep it running with the choke off, what does the vacuum gauge read then? Is it bouncing around?
How about the plug wires, are they even in the right order? Do you have a misfire on one or more cylinders?
Have you done a compression test to see what your engine is really doing?
If you have checked the boots and the end castings by spraying them without any noticeable change in the way the engine runs then you can rule out an air leak there, but what about the ends of the throttle shaft? Have you sprayed carb cleaner there? Loose throttle shaft bushings will create all kinds of trouble when you go to adjust the idle because of all the extra air getting into the engine through the ill-fitting throttle shaft. The carburetor is not metering against that air, thus the thing runs like crap and frequently stalls. You'll
-never- get it to idle right. The only way to fix it is to have the bushings replaced. Checking for this problem is pretty simple. Remove carburetor, remove the throttle return spring, open the carburetor to full-throttle, and grab the ends of the throttle shaft. Can you wiggle it around inside the base of the carburetor? If so, you have a problem that must be repaired before troubleshooting your issue any further. Contact rimco in california to have the bushings replaced.
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Now you've got me confused. First you say it dies when the choke opens. Now you say it dies, but if you restart it it runs 'pretty normal'??? But then just a few lines further down you say this
"> Also when the engine is at running temp it still runs rough or/and wants to die. Before it only did that when cold."
So can I assume it runs poorly and sometimes dies once the choke opens? See above, what you are describing could have many different causes outside of the scope of your carburetor.
Yes, this would seem to indicate your carburetor is leaking fuel, probably from either the fuel inlet or the top cover gasket. Remember, leaks usually only go down. Follow the trail of goop upwards until it stops and have a close look at that area.
The issue with residue on the decklid is probably partially coming from the carburetor cleaner you were using to test for leaks. If any of that hits the fan belt it will get slung up into the underside of the decklid.
In reviewing your past posts to RAMVA I failed to find a message saying you had performed any of the basic tests to verify the MECHANICAL condition of your engine, such as a leak-down test or compression check.
Your symptom -- rough running -- could be a bad valve, worn guides, worn or broken piston ring(s) or a combination of those things. Indeed, your engine could simply be worn out.
The more tinkering you do with your carburetor and ignition timing makes it painfully clear that whatever the root problem, it is something OTHER than the items you've addressed, which begs the question, why continue to beat a dead horse? Any effort to properly diagnose the problem will be fruitless unless you include the basic tests.
The only thing *I* can do is a compression test (have a hobby-kit) If that fails I'm bound to take it to a shop and have them have a look at it. It's a pitty if I'm not able to do(solve) it myself (with RAMVA of course:))
Thanks again Bob If anything comes out I'll post back, result or more Questions
I've done most of the things you mentioned prior to this Post. Except looking for leaks at my carb.
When the bug stalls the engine is not warm enough but the choke is off... Mostly , if I restart, the bug runs without stalling...mostly I wish i could explain why... But now it is getting worse, it wants to die/stall even after running on the highway.
Indeed, Bob Hoover mentioned that too, will have a look at the compression..
Now that Volkswagen has abandoned the owners of its air-cooled vehicles, taking your bug to a 'shop' may be the LAST thing you want to do. When it comes to antique vehicles YOU are your best mechanic. If you lack the skills, time & tools to do your own maintenance it may be best to buy a vehicle that is still supported by its manufacturer.
Track down the 'TULZ' series and give them a good read. (They are in the RAMVA archives.)
as a LAST resort - you could go for an engine swap - scoobie or somthing similar. You would have to hold on to your pants when you stomp on the gas ! but you could get mech support from your local subaru dealer ! Alfa engine fit pretty easy too.
Personaly 'I' would keep the aircooled engine - but I can work on mine. If you are seriously out of your depth with the air cooled stuff, it worth considering ? you get to keep the bug :-) and it will be faster that anyone elses ! (anyone elses anything for that matter ! )
I found the compression test explained by Rob and Dave
When i canged the sparkplugs they looked brown ish and dry, good to my opinion (based on Haynes).
By 'shop' I don't mean the VW dealer.. I'm with you on that! There are a fair amound of ACVW shops in my little country, I know how to find the right one(s). (thanks for the heads up) In the end I have a friend who is mechanic, (has several ACVW's) He is very busy though... Maybe if it comes to going to a shop I might ask him to help, so that we can do it together, and I might learn something.
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