Question for people still running ignition points in a 009 dizzy

[helowrench]

As far as how long a set of points last, I will input a bit of my findings.

Background: I am running a DIY transistorized add on system that uses the points only for a switching/timing input. Therefore the points electrical path is only passing 5v (IIRC) and milliamps.

Therefore I will weigh in on the mechanical side of their construction.

I see roughly 50K miles per set, as long as I keep the cam follower block well lubricated. Initial settings never change until that block does......... or the pivot point.

Around 50K miles I start to see a spurious tach needle "bounce" that does not correspond with the ear. Once that begins, I usually have about 500 miles before the points ground out, and stop working completely. I suspect this is pivot point wear, losing its insulator.

As for the points contact face, since I am running such low voltage/amperage through them, at 50K miles, they are just as perfect as when new.
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Current VWs:
70 bug vert for wifey
73Thing bucket o rust
73 914 1.7
12 Passat 2.5 Highway cruiser

[raygreenwood]

[EVfun]

[raygreenwood]

[EVfun]

[modok]

[Dale M.]

FYI.... Comp-u-fire is now owned by Pertronix...

Dale
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“Fear The Government That Wants To Take Your Guns"
"Kellison Sand Piper Roadster" For Street & Show.
"Joe Pody Sandrover" Buggy with 2180 for Autocross (Sold)
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All suggestions and advice are purely my own opinion. You are free to ignore them if you wish ...

[raygreenwood]

EVfun....I was simplifying a bit....I know why the points transfer metal (where the current comes from)....and when it transfers.....but the end issue is the same. They transfer metal when it gets hot....and the issue...its effect on dwell...... is still the same....not that its a huge issue on most cars that use them but it does make for a less distinct dwell curve.
I work in the electronics industry as well....and so undertand ths issues. I dont need to look it up

Your comment about the dwell being a slope instead of a square wave....is spot on and is a better explaination of exactly what I was pointing to.

I am also totally aware that transistors change with temperature..... however for the functionality of this particular part.....the temp change curve of the single transistor being used as a switch in these modules has virtually no measurable effect within the system using it.....which is the collapsing field of the coil.

This is not the same problem encountered with temp change when you have numerous transistors all having various levels of temperature related switching time/frequency....on an epectronic board......that may be singularly or cumulatively affecting signal quality.

Yes.....totally agree...that if you want to say the cracked magnet ring was part of a failed "package"....therefore the package or unit sucks and should be discarded/replaced.....no argument there.

However....having done troubleshooting on many of these systems......both frozen and heated because this same scenario has been suggested before.....and one one point in time almost 20 years ago...even suggested by me when troubleshooting odd ignition issues with a pertonix.....I found that in our engines the variation that happens due to temperature extremes in the single transistor switch....has no noticeable or measureable effect.

Does this mean that when stacked up with other issues it wont have an effect?....heck no.

But it begs the question..........if you are allowing your distributor to have other variables and inconsistencies stacked up that react and can be leverage by the otherwise negligable variance the switching module may have at temp extremes.....why is that the modules fault when those other items are correctable.....and not normal or within spec?

Your temperature related symptom....fits a change in magnet position either due to as noted...a crack starting....AND....not just OR....because there is no way to avoid this......the same temperature expansion that affects the 30 or so parts in the distributor.....that wear over time, contract when cold and expand when hot. Its usually parts attafhed to the magnet rotor or breaker plate moving, expanding and contracting.....that are the issue.

This is all I was getting at.
You say its an electronic problem.
It sounds like you assumed it was due to transistor temp variance (a problem that would be exceedingly rare or non exustent on THIS type of system).....when in reality....it was most probably a mechanical issue with the magnet rotor. We have no way of knowing for sure if you tested for nothing else. The fact that the magnet ring fell apart....implies it was crafked. If it was cracked.....it runs out of spec and changes with temp.

Yes....the magnet ring is part of the package so its the packages fault.....but not the same thing as a failure of the electronic part.

I make the argument....because far, far, far too many people simply state that these parts are electronically unreliable....because they had one that left them in the side of the road.......but most never bother to find out exactly what failed.....or if it even failed at all.....or due to slop all over the distributor system.....is simply running so far out of spec that it cannot reliaboy trigger.

I just think ....due to experience....that other than build quality issues over some years and brands....just like we get with points......which have left just as many on the side of the road (and that sounds like what happened to yours....but it just as easily could have been machining variances not fitting a molded part properly)......these these type of units get a bad rap for no reason.

I have actually worked on far more of these for other people..... than I have ever owned....simply because when well sorted out in a distributor that is in good shape on an electrical system in good shape.....they rarely fail.

I cannot tell you how many times I have driven out to help a stranded friend...and not just in a VW....more Saab, BMW and Volvo than VW........and the pertronix just wont start the car. The owners swears violently.....that its that electronic piece of sh*t! Put points in and get it home. They seem to be right....right?

Spend an hour or so the next day with the dizzy out and stripped.....and find a crap load of axial slack in the shaft......a shaft bushing that is more excentric than Andy Warhol.....sticky advance weights, advance plates that are warped due to ham handed tightening with the wrong screw....advance weights stuck together with 20 year old grease....many of these utems change a good deal from hot to cold weather ...not to mention crappy connections and connectors, ......a whole slew of little items that make for an odd stack up of tolerances, shaft run out and axial play being the largest.

Clean it up....add some new parts.....and install the same module that everyone swore was a dead POS yeaterday.....and it fires right up. I cannot tell you how many times this has happened.

Modules are sensitive to slop.....that points are not.
While one could argue that this is bad..... in actuallity its simply the price of admission with this part if you want to use it for its benefits.
Trying to use a pertronix module just like a set of points while not doing one thing different upon installation....can potentialy be what causes them to fail. Ray

[Dale M.]

[EVfun]

[modok]

I am glad you are interested in these things.
Handy hint....how do you know your condenser is the right size?
If the value is too large, generally you will see material transfer on the contacts the opposite way as usual.

[raygreenwood]

[EVfun]

[raygreenwood]

[raygreenwood]

[quote="raygreenwood"]