Worn out distributor

[anthony]

After chasing down some minor running issues that I thought were fuel injection related I've come to the conclusion that my distributor is worn out.

I say this because the dwell tends to jump around. I had it set to 48. The car was running superbly. A few weeks later the car is running like crap and sucking down lots of fuel (low mpg). I found the dwell had risen to 55. I reset it to 46. Car is running great again. Recheck again a couple days later and the dwell is 44.

The dwell will move about 1.5 degrees when I rev the engine from idle. Points, cap, and rotor are new.

I also have the other classic indicator: jumpy timing mark syndrome.


What are my options? I mean besides buying a "new" distributor for $600.

[Rouser]

Properly and carefully install a Pertronix Ignitor breakerless module into your worn distributor.

The unit is way more forgiving and tolerate of wobbley shafts, and you can ditch the points and condenser (OK; you can toss them into the glove box, in case you want/need to swap back to original config).

Short of purchasing a rebuilt unit from A-1 Cardone (at any participating FLAPS) for around $100, it solved the same problem on a friend's FI 914 2.0L. I've been running an Ignitor goin' on 3 years now, no problems noted.

[anthony]

Where's the best place to buy an Ignitor? I see that Pelican sells a Crane unit. I like that the Ignitor doesn't have a black box that I would have to mount in my engine compartment.

The other thing I noticed about my distributor is that when I pulled off the rotor the shaft went "pop", like a joint poping out of the socket.

Every once in a while, the car looses power, for less than half a sec. I think I read here that a new distributor fixed a similar problem for someone else. The theory being that the FI trigger points were affected by the worn distributor.

[Rouser]

Best place to buy it? Let's see ... how 'bout right here: Ignitor (Pelican Parts).

They also sell the FI Trigger Points, but I would attack one item at a time, if only because it might be an ignition problem before a FI triggering problem.

[Ron Meier]

Pull the cap, pull the rotor and push the point cam/distributor shaft side to side. It shouldn't move. If the shaft bushings are worn out to where you have a lot of side movement, the dwell and timing will vary considerably as it rotates. The point gap (dwell) will change as the point spring places more pressure against the shaft as the points are opened. Same goes for the timing as the desired point opening in degrees will vary as to the "pressure" placed on the point lobe by the point spring.

This condition can also be duplicated with a good distributor and old points as the rubbing block wears. At a certain point, rubbing block wear will accelerate rapidly.

Be aware, the the point cam on the distributor shaft can wear too. This causes much the same condition.

If the points are to close, the dwell is not sufficient to allow for saturation of the coil windings and you will experience weak spark ~ read as poor running, fouled plugs. If they are constantly to close, the car will not run at all.

If they stay closed for extended periods with power to the circuit, the coil will overheat and explode (sitting with the ignition on and engine not running, points closed).

The "black box" CD ignition systems won't do this.

One other problem I ran into with LED triggered systems was to hot of a spark from the "high performance coil" to the distributor. The spark jumping from the rotor tip to the distributor cap post created light inside the dizzy and triggered the LED randomly ~ read misfiring and timing jumping all over the place. Voltage to the primary winding of the coil is 9 VDC and if you don't put a resistor in line, full voltage (12-13 VDC) to the coil will cause this.

Just my $1.00 worth

[yoh!!!]

Important: Stop reading in case your car is equiped with an original FI System!!! Keep going when your 914 is convereted to carb (s)...

For a while I was thinking about using a original Bosch ignition with a hall sender. Most of the VW in the 80's used this system. I found that the Vanagons build from 83 to 85 used dizzy's that would fit the old type IV cases at the same time the advance curve looked appropriate. TZS units and wiring harness fit with minor modifications and are easily available from all kinds of VW, BMW, Audi, ... products of the 80's)
I'm very pleased with my current setup. I can't compare it with an Ignitor (I or II) because I never owned one. I'm more confident that this setup might be more reliable than the Ignitor. Check the archives for issues with the Ignitor system....
... the cost for my (used) system (incl. black box) $15.00.


Patrick Koch

[Bleyseng]

Sounds like a worn distributor and that is a easy fix. Just get a rebuilt unit from a FLAPS mostly they sell a unit for 1.7l but they are very close to the same (the advance curve is slightly different so don't toss you 2.0l one).
Install a Pertronix first, then install the dist into the car, time it to 27 degrees btdc.
Gone should be the wobbly timming mark and overall better preformance. A worn dist. will affect the FI too as it controls the injector timming.
This is one of the basics for smooth FI operation- a good distributor! (I just got though helping a friend fight FI problems, he kept saying the distributor is good I checked. Finally I checked it and he bought a rebuilt unit and I was able to finally get the car running right! He will remain nameless to protect the innocent)
Geoff

[Dave at Pelican Parts]

Patrick, the Vanagon distributor will also work fine on an L-jet (e.g., 1.8 914) car. It's just the D-jet (1.7, 2.0) that needs the distributor with the FI trigger points in the base.

Bleys, the FLAPS rebuilds (A-1 Cardone does them, I believe) are fairly hit-or-miss. You should check them as well as you can in the store! For the price, it's hard to believe they do much more than replace the points/condensor/trigger points/etc. You can't hardly buy those parts for what they charge for the whole distributor--at least, in some cases...

--DD

[Bleyseng]

Dave,
I guess I have been lucky so far, all have been rebushed to fix the slop in the center shaft.
One unit came with defective trigger points but other than that ok units for the price.
By all means if you can afford new go for it!
Geoff

[azkiwi]

My points just failed (the plastic part that rides on the cam of the distributor shaft broke). I had purchased an Ignitor about a month ago and now had the excuse to install it.

I guess my distributor was worn out because since I installed the Ignitor I no longer have the jumpy timing mark when setting the ignition timing. It is much smoother at idle and I have been able to eliminate the resistor I placed in line with the cylinder head temp sensor. All this time I thought I had a lean running condition when in fact it was the distributor.

While doing the swap I found a short in one of the wires coming off the "-" terminal of the coil. When I put a new terminal connector on...that fixed my bouncing tach.

I took it on a 100 mile shakedown run this morning and so far so good.


Alex

[green71]

I just installed a rebuilt ($90) distributor and an Ignitor. Gotta say, I'm tickled with the setup. Smoother idle, smoother in general, no more dwell to set, 29mpg . . .

There is a ball bearing held inside the distributor by a bent metal spring . . . this assembly is right next to where the points are. Don't know what it is or what it does, but I've heard that if the bearing is not held firmly in place, dwell will wander. I loosened the spring & clamped it down tightly when I installed the Ignitor. Can anyone corroborate this? What the h*ll is it?

[anthony]

I just ordered one of the A-1 Cardone units from Kragen's web site (partsamerica.com). Cost was $60. I'll think about getting the Pertronix next time I make an order from Pelican.

[Dave at Pelican Parts]

I believe that the ball bearing is what the breaker plate rides on--or at least the top part of it. The points (or Hall effect pickup, whatever) have to move around inside the distributor to advance and retard the timing. This is done by having the plate that the points bolt up to (AKA the "contact breaker plate") free to rotate to a certain extent. The ball bearing, I believe, supports the moving part of the breaker plate.

Too tight might shorten the life of the plate.

--DD

[anthony]

So I received this Cardone distributor yesterday. They sent me a distributor with a 1.7L part number. My car is a '74 2.0L. Have people had this same experience with Cardone or is the problem with the vendor (partsamerica.com in this case).

[Bleyseng]

They only rebuild them to the 1.7 engines spec (so it fits a 411 too?) but the difference is a minor change in advance curves. Keep your 2.0l dizzy if you want you can switch out the advance weights.
Check the FI points to make sure they are new and not defective.
Geoff

[anthony]

Success today! I repaired my old unit. The circlip that holds the
top part of the shaft in place had actually come undone which allowed the top part of the shaft to move up and down an extra 1/4 inch. I took my dizzy apart, cleaned and lubed it, and put it back together with the circlip and now it seems much better. It still has about 1/8" of up and down play in the bottom of the shaft but no side to side play. The dwell no longer seems to be wandering, the idle is better, the timing doesn't jump around so much and the car drives 100% better.

I just returned the rebuilt unit. Kragen was pretty good about the return and they refunded shipping. They also confirmed that they only have one part number for 1.7 and 2.0L engines. The vacuum advance unit on this distributor was also incorrect for my '74 2.0L. Another problem was that the rubber o-ring was too big and I couldn't even get this thing in my engine.

[Ron Meier]

The up / down slop in the dizzy is to compensate for the up/down movement of the dizzy drive gear (driven by the crank). Two beveled gears running together, the driven gear will try to "climb" the driving gear (screw itself out of position).

If you ever take it out again, inspect the circlip groove. See if it has been widened.