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Thu Sep 29, 2016 2:06 pm

Howdy all,

I recently replaced the distributor cap, wires, plugs, coil and hall sensor on my 84 1.9 vanagon. I followed the widely available diagram for wire replacement and firing order and am getting both spark and fuel to all cylinders, however the timing seems to be exactly 180 degrees off. While replacing the hall effect sensor I had to pull the distributor, but realized on reassembly that it only goes back in one orientation.

I have searched extensively on this site and the general interwebs for a clue towards what I may be doing wrong, but no luck yet. Many posts on this site have been helpful in figuring out my van and I hope someone else has previously solved a similar issue.

Thanks for your help

Thu Sep 29, 2016 2:19 pm

On VW's that have been worked on by others who had less than perfect knowledge, the distributor drive gear can be installed differently than how the factory did it.

That means that #1 cylinder could be almost anywhere on the 360* circle of the distributor!

You need to find out WHERE it is and then rearrange your wires in the proper order.

In the future NEVER pull them all o the wires off at one time but rather replace each wire by itself, pulling off one old and install one new in its place until all four are complete.

But, find the TDC mark on the crank pulley (a large "dent" on inner belt guide but one removed from the engine case. The mark closest to the engine case Is a fine filed slot and is used for timing the ignition and is NOT too dead center.)

Rotate the engine until the dent is up and centered. This is top dead center for cylinder #1 & #3.

You've got a 50/50 change of it being #1.
Pull the distributor cap, where is the rotor pointing in relation to #1 plug wire terminal?

You can verify #1 TDC by popping the valve cover and looking to see if the exhaust valve rocker is compressed or not. If it is, you have #3 TDC. Rotate one full revolution to put #1 at TDC.

Dave

Thu Sep 29, 2016 2:28 pm

Provided you the distributor is orientated properly and the dog ears are in correctly, it is possible that a past mechanic accidentally put the distributor drive shaft in 180deg off. It is a common mistake. The easy way to deal with that is to shift the position of the sparkplug wires 180deg. The important thing is to verify that #1 is at TDC, observe where the rotor is pointing and make sure that that spark plug wire on the cap is going to #1. Then install the rest of the wires accordingly.

Hans

Thu Sep 29, 2016 2:45 pm

Thanks, fellas. I'll investigate further and post back.

Thu Sep 29, 2016 3:11 pm

Rotating the wires fixed the problem. They are especially tight, but it worked. Thanks for the help.

Thu Sep 29, 2016 3:17 pm

Glad it was that easy!

Hans

Thu Sep 29, 2016 3:46 pm

Where did you get a Hall Sensor for a 1.9? Was it new? Glad it worked out.

Thu Sep 29, 2016 4:08 pm

I thought it had been from Van Cafe, but they don't seem to have any currently listed. It was early this year.

Thu Sep 29, 2016 4:56 pm

Always just put the wires back on just as they came off and you will not have this problem. The easiest thing to do is just take the cap off with the wires still attached and set it aside. If you do want to change out the cap then install the new cap onto the distributor and move the wires one at a time from the old to the new cap.

Thu Sep 29, 2016 4:59 pm

I could have sworn I got the wires in the same spots during the switch. Is there another way that I might have screwed it up? The old wires were the same length but weren't stretched nearly as tight.

Thu Sep 29, 2016 5:45 pm

Are you absolutely certain you got the distributor fully locked into place? The dog gear will kind of grab when it is 180° out and can actually run for a long time that way. My 83 1/2 POS was that way when I acquired it and from the wear it looked looked like it had been that way from many tens of thousands of miles.

Loosen the hold down clamp (13mm nut) and then try and spin the rotor using a fair amount of force, if it is correctly aligned you will not be able to move it. Could also be like in the case of my 83 1/2 that it was in wrong to start with and you put it in correctly. People are amazingly inventive in coming up with ways to gets these parts in wrong.

You can always go back to square one and reset the distributor drive according to the manual, but there is still the off chance that the gear on the bottom of the distributor is on backwards thus throwing everything off.

Fri Sep 30, 2016 1:25 pm

My guess is that he drove the pin out that holds the keyed gear on the end of the distributor shaft without making careful note of the position. Then he put the pin back with the gear rotated 180 degrees from where it was.

Mark

Fri Sep 30, 2016 1:41 pm

Hi Mark,

I did not drive out the pin earlier but rotating the keyed gear now would be an excellent way to relieve tension on the tight plug wires.

Thanks for the suggestion!

Cheers,

Joe

Fri Sep 30, 2016 1:50 pm

OK, I've got it. Pardon my short-term memory problems, but what I had forgotten about was the orientation of the shaft when the distributor came apart while I was prying on the shutter wheel!

I had thought I was going to have to purchase a new distributor, but I found both springs after setting the parts aside for two days and reassembled the unit. Obviously, I reassembled it 180 degrees off.

Thanks for everyone's suggestions. I'll take the distributor apart again and reassemble it in the correct manner.

Sat Oct 01, 2016 10:21 am

I've been wrenching for over 40 years as a serious hobbyist. Messing with timing is a part of any project where I always go the extra mile to document and/or mark things to ensure it goes together well. The boards are full of people trying to figure out why after months of work they can't get their engines started and it often comes down to a distributor mistake.

So, a Sharpie is your friend. I always, ALWAYS mark where the cap was in relation to the distributor, put the cylinder number on the wires, and mark where the dist body was in relation to the block. That way, putting things together is a breeze. Look under the hood of any of my cars and you will find these marks so that if I'm in a campground and something needs to come apart, it will go together right. After all these years, its somewhat of a mark of pride.

Doug

Sat Oct 01, 2016 12:25 pm

Solid advice, Doug, thanks. Having never before taken apart a distributor I probably should have been photo documenting the process at the same time. It usually takes me two or three screw-ups to permanently learn a lesson such as this, but mild public humiliation is a strong teacher.