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Thu Dec 27, 2007 6:52 pm

Ive adjusted the valves 4 times. (used the pencil trick to find TDC)
Ive spent hours, and hours, and hours adjusting the carb.
I went out and bought that distributor you told me to get.

I set the points on the dwell and they are at about 44 to 45 degrees

I HAVE NO IDEA what else to do. Ive spent so much money, and time working with the timing, the carb, and valves. and it still bucks like a bronco the way it did 5 minutes after I first got the thing running.

timing is set to 7.5 degrees BTDC right?

im just so worn out and SICK of this engine. Ive timed and tuned plenty of 1600DP's and never have I had this much trouble with ANY of them. the worst fucking flat spots i have ever dealt.

Thu Dec 27, 2007 7:40 pm

Just out of curiosity, and for no other reason, what type carb and distributor do you have? I have a dual vacuum dizzy that is a bitch to set.

Now, just a little comment here. Some 1600s have to be set to 5 ATDC,depending on the model year ect. Try this link, Http://www.aircooled.net and check out their technical pages, they have one on distributors and carbs that might help. The chilton manual , which I don't generally consider very good, has an excellent table that lists all the timing for most type 1s.

I hate to give advice because you have probably done everything humanly possible

Thu Dec 27, 2007 7:51 pm

Calex59 wrote: probably done everything humanly possible

That might be an understatement..
:lol:

the carb is a 34pict 3
dizzy is a BRAND new as in 4 hours ago single advance dizzy.

Thu Dec 27, 2007 7:54 pm

What plugs are you using?

Thu Dec 27, 2007 7:56 pm

The 34PICT-3 can be difficult to tune. Do you have a experienced VW mechanic locally you can bring it to?

It might be worth paying an hour of his time.

Thu Dec 27, 2007 8:01 pm

Incorrect timing or carb tuning shouldn't cause "bucking". Sounds like the firing order may not be correct or yuo may have a dead spark plug or plug wire.

Thu Dec 27, 2007 8:01 pm

heres the way it is right now. the small screw is out about 2 and 3/4 of a turn. and the big screw is out about 1/2 of a turn.

let me just double check that with the new dizzy i just threw in the timing is now set to 7.5 BTDC right?

Thu Dec 27, 2007 8:03 pm

56ovalbug wrote: Incorrect timing or carb tuning shouldn't cause "bucking". Sounds like the firing order may not be correct or a dead spark plug or plug wire.

its not neccesarly bucking. If i advance or retard the timing that changes is. its just a series of annoying flat spots. the only way to avoid them is to drive VERY light on the throttle all the time, going up hills becomes a nightmare.

Thu Dec 27, 2007 8:03 pm

Quote: Timing Set At:: 7.5deg BTDC @ 800-950rpm w/strobe and w/single vacuum hose disconnected and plugged

Thu Dec 27, 2007 8:06 pm

looking at the distributor this is how the firing order is set right now

front of the car
2 1
0
3 4

Thu Dec 27, 2007 8:07 pm

Glenn wrote: Quote: Timing Set At:: 7.5deg BTDC @ 800-950rpm w/strobe and w/single vacuum hose disconnected and plugged

oh wow so do I need to plug it on the carb and the dizzy?

Thu Dec 27, 2007 8:09 pm

Don't assume... the distributor has a mark on the top edge that is the location of #1. It's not always as the same location on different distributors.

Here's the location of the cylinders.

Make sure the spark plug wire from #1 goes to the #1 on the distributor. Then going COUNTER CLOCKWISE put on #2, then #3 and finally #4.

--------------------------------------------------------------------------

Personally if you have the wires on wrong, the engine won't run.

Thu Dec 27, 2007 8:23 pm

92slc wrote: heres the way it is right now. the small screw is out about 2 and 3/4 of a turn. and the big screw is out about 1/2 of a turn.

I'm thinking with the bypass screw in this far the engine shouldn't even run - sounds like a vacuum leak.

http://www.vw-resource.com/34pict3.html#carb

Thu Dec 27, 2007 8:24 pm

92slc,

As a Newby, I've felt the same frustration. Let me suggest that you just lay down the wrenches, back away from the car for a bit, rethink what you have done and the sequence of the tune. Valves, dwell, timing, carb. Review http://www.vw-resource.com/carb.html#pierburg

I have to remind myself of the KISS, Keep it Simple. It's often a simple thing I've overlooked.

A few questions:

You said the engine was "bucking". Is it not idling smooth? Is it missing? Plug wire on distributor reversed? How are your plug wires, rotor, distributor cap? Is it "bucking" at startup or after warm up?

Just a few ideas from a Newby.

Thu Dec 27, 2007 8:46 pm

The most basic definition of crazy is doing the same thing over and over and expecting different results.

You need to start suspecting other things, like wires, cap, rotor and/or plugs. If you have timed it, adjusted the valves, adjusted the carb and you are still getting the same "bucking". Guess what, I really doubt it's any of those items that is causing it, or you have done it incorrectly each time.

Maybe you carb has junk in it, maybe your fuel filter is getting clogged, maybe one of your plugs is fouled. Plugs are cheap. Wires are more. Cap and rotor are reasonable. Something else is causing it...

"Bucking" is often confused with a "miss"... just a thought. Especially in a 4cyl engine.

Thu Dec 27, 2007 11:06 pm

okay I forgot that the single advance is timed plugged up. Ive been doing it with my old dual connected previously.

Now the bypass screw isnt supposed to be out as far as I have it out? (half a turn) how far does it usually come out?

does the small screw usually come out about 2 1/2-3/4 like i have it set right now?

Fri Dec 28, 2007 5:53 am

I had a similar problem with my H30/31 carb some time ago. The problem turned out to be a piece of debris in the main jet. Have you tried removing the carb jets and blowing them out w/ compressed air (along with all of the passages in the carb)?

You mentioned that going up hills was a nightmare. This makes me think that as you give it more gas you are getting more into the main circuit. Hence, your trouble.

Fri Dec 28, 2007 7:35 am

92slc wrote: Now the bypass screw isnt supposed to be out as far as I have it out? (half a turn) how far does it usually come out?

does the small screw usually come out about 2 1/2-3/4 like i have it set right now?

2 or 2 1/2 turn out for each screw is where you start off - this should get you close to where you want to be, you need to read this: http://www.vw-resource.com/34pict3.html#carb

Fri Dec 28, 2007 7:37 am

92slc wrote: okay I forgot that the single advance is timed plugged up. Ive been doing it with my old dual connected previously.

Now the bypass screw isnt supposed to be out as far as I have it out? (half a turn) how far does it usually come out?

does the small screw usually come out about 2 1/2-3/4 like i have it set right now?
You have to disconnect and plug all vacuum lines. Disconnect and plug the can on the distributer. Plug the vacuum intake where it enters the carb. Plug the line in the intake manifold below the carb (if you have one). Plug the EGR intake at the rear of the carb (if you have one). Plug any other vacuum lines on your carb. Only then can you set the timing.

Also (as I've been reminded to do myself), 2-1/2 turns for the small screw is just a starting point to get the thing running. After warmup you should turn it in (or out) until you reach the highest idle. I recently did this on my sedan, and the rpm went from ~850 to ~1100 by turning it in about 1 turn. You then reset the idle to 850-900 using the large (bypass) screw.

Fri Dec 28, 2007 7:41 am

mnussbau wrote: Disconnect and plug the can on the distributer.

you don't need to do this.

mnussbau wrote: Plug the vacuum intake where it enters the carb. Plug the line in the intake manifold below the carb (if you have one). Plug the EGR intake at the rear of the carb (if you have one). Plug any other vacuum lines on your carb. Only then can you set the timing.

you need to do this.