[T3] Dist trigger points?

[Jim Adney]

On 10 Sep 2022 at 21:58, William Jahn wrote:

> I noticed the three sets I have. On all of them if you look at the curved
> plate that is secured to the dist body and then look at the plate the
> trigger points are secured to the two are not at a 90 degree angle. Is
> there a reason for this? One set I got new in 2002 and it's the same way.

I just looked at 3 sets that I have, and they all look perpendicular to me. I 
don't think there's any reason for them to be otherwise.

You don't say which way they are bent. The U-shaped inner plate actually 
rests on a sort of shelf in the distributor body when it's installed. If your 
plates are bent very slightly downward, this would assure that they were 
pressed against that shelf, and tightening the mounting screws might 
actually bend the plate back to perpendicular. That might be a good thing.  

If your inner plates are bent upwards, toward the rotor & cap, that would not 
be good.

> I did notice the point rubbing blocks are not worn at an angle and looking
> at the cam it's not tapered that I can tell.

I agree, no taper on the cam or rubbing blocks.

For the record, I have never bought a new set of trigger points and never 
needed one. I HAVE experienced points where the rubbing block had worn 
enough to cause problems. This can be fixed by bending the fixed contact, 
but you need a proper jig to know exactly how far to bend it. I reset these as 
a part of every FI distributor rebuild ($65.) I can also reset them for $5 if you 
just send me the FI points. Plus shipping, of course.

I was caught by this on our trip to the Alabama Invasion. Halfway down, the 
engine started to miss, eventually getting so bad that we had trouble getting 
to a motel and park. It took me several hours to track down the problem, but 
once found, it was a quick & easy fix. I had rebuilt that distributor long ago, 
but it turned out that this was before I had figured out, and made, the jig I 
needed to do this.

BTW, when I finally got around to making this jig, someone on this list sent 
me several FI trigger points, some NOS, to use as references. One of the 
NOS sets came in a plain white box, no brand ID of any kind. That one was 
clearly not Bosch, with a rather clunky looking electrical connector. In the 
end, I discovered that it was completely non-adjusted and would have been 
completely worthless in a car. I reset it and it should be fine.

For those who like details, there are 3 generations of FI trigger points, but 
they all interchange.

1st gen: points pivot on plain shafts and can be lifted off those shafts

2nd gen: added staked washers on top of pivot shafts, so the points can no 
longer be slid off. Distributor bodies for these, '70 and later, have extra 
notches to clear the taller shafts.

3rd gen: small steel shields added to the moving points in an attempt to keep 
dirt out. I don't think they are helpful, because the dirt seems to come from a 
different direction.  

-- 
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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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