First installation attempt on a VW Type 1

[Luca Lagonigro]

Mr. Overbudjet says:

I've tried the new sensor (SMP PC18 equivalent) over the weekend, the signal is the same as the ABS sensor, this leads me to think that there is something wrong with the thoothed wheel.

Amplitude is always around 1Vpp Max. that's way far from what I've seen around as spec.

mmmm....

Nex I'll buy a new 36-1 wheel.

Part n°?

[bsimon]

Just throwing out some ideas here...

I've looked at your installation photo. Are the teeth of the wheel standing well above any nearby rotating parts? It looks as though you have a flange on either side of the toothed wheel that are the same outside diameter as the toothed wheel. I don't think the VR sensor will generate good pulses if the adjoining flanges are made of a ferric substance. It would result in an effect similar to having the teeth cut with too small of gap between them. ie; low output voltage. The sensor needs to see a clean break between teeth.

[Luca Lagonigro]

I thought about that, I've built the test bench by simply using the triggerwheel alone (whithout the pulley) attached to a drill press.

My idea is that the teeths are etither too close, not leaving enough air gap between them or maybe not deep enough. Even if I've compared my wheel with other pics on the web and there is, apparently no significant differences.

Keep the ideas coming!

[Luca Lagonigro]

Here are some shoots at the "test bench" and the sensor bracket:

http://community.webshots.com/album/344012358LqTcEq

[tedzbug]

So how did the test go?

What are the specs of your engine, intake, etc.? If you dont mind.

I am getting ready to run this setup on my '75 super beetle and doing some learning myself.

[Luca Lagonigro]

This are my plans:

- 1300(F)Single Port stock rebuilt. This engine is in my vert and will receive the MJLJ as I intend to retain the carb.

1300 SA:



- 1600 Dual Port stock rebuilt. This engine is still one the table but it will be installed in my '62 along with a turbocharger and Megasquirt'n'extra for fuel and spark (EDIS).

Courrent engine in the '62 sedan:


Next '62's engine:


Next week I'll test again on a real (working) 1600 DA engine at a friend's place. I'll post the result.

Friend's engine:

[bsimon]

Luca,

In your recent test bench photos, the trigger wheel looks as though it should work fine.

I can't figure out why you're not getting a reliable trigger signal.

One thought I had was the trigger wheel material. Is the wheel made out of something weird like a high nickel content steel? The wheel needs to be magnetic. Stainless won't work unless it's austinetic, chromium based. Nickel based stainless isn't magnetic.

Another thought; Have you shielded (screened) the conductors leading to the VR sensor. I understand they are quite sensitive to external electrical noise. With the business end of the spark plugs exposed on your test bench, this might be the problem.

[bsimon]

Luca,

While I was seaching this site i found some reference to VR sensor polarity. It seems that the sensor needs to be hooked up properly in order to provide the right signal to the EDIS. Might be worth checking out as well...

[Luca Lagonigro]

Well I don't know what to think,

the wheel is made of mild steel and it's mgagnetic for sure as he sensor stick to wheel itself.

I did the measurements at the pick up connector with a shielded probe cable, connected and not connected to the edis module, I've also reversed the polarity a couple of times.

Now I think it's impossible to have two different sensors acting exactly the same, It must be the wheel (but really looks it should work) or the Oscope itself with a bad input circuit.

I'll have to stay away for a week or so due to work... but the engine is ready for the next attemp.

I'll keep you informed...

Thank you guys!!

[Luca Lagonigro]

Brent, this forum is terrible!

[Ivan]

How did you get your pics on here like that?
Ivan

[brentp]

Whatever
do
you
mean?

[bsimon]

Brent,

I'm not speaking for Luca, but I do have one comment.

Is there some way you could turn off the subject line for users when replying to posts? Everyone seems to be replying with a new subject line so the message thread becomes incongruent. If replies automatically had the current subject line included, it would force users with new topics to start new threads instead of turning them OT. The search engine would also be easier to use if threads remained intact.

Just a suggestion...

-Bob

[dermot]

Hi,

Don't know if it helps or is even relevant but I noticed the following in your pictures Luca;

Your trigger wheel does not look as if it is exactly 50:50 mark:space, i.e. the "teeth" are not the same size as the "gaps"... is that so??? -if it is, that would mess it up, I believe it needs to be 50:50...you won't get a 'nice' waveform otherwise!

Also, the height of the teeth needs to be enough, otherwise there won't be enough variation in the reluctance, again, that looks slightly "shallow" - is it similar depth to a Ford wheel??

br

Dermot.
====================

[tedzbug]

This is an old thread, but i am looking for an igntion map for an aircooled vw engine.........