Jaycar Kit KC5442 with Reluctor

[Celica_73]

Just wondering If anyone else has built this kit the Programmable Ignition Mk2. I'm am currently having problems and looking to compare with a working system.

As I'm installing both the Reluctor from a 21R into a 2T Dizzy and the Kit at the same time I'm unsure where the problem is. After installing both into the car I used the oscillator feature to set the dwell time (Spark spacing was varying, not normally from my understanding).
At cranking speed there was no spark from the coil. Pulled the system out of the car and did some bench testing. At low speed (roughly cranking speed) the signal from the reluctor is only 1Vp-p but from my understanding the Circuit requires 5V to work. So disconnect the dizzy and placed a signal generator in it's place. Nice clean spark and regular interval with a 5Vp-p signal and also accurate tacho feature built in. So I'm pointing the finger at the reluctor at this point but as I have not play with one before not sure what result I should be getting.

Cheers
Jason

[petergoudie]

Jaycar kits are usually made by Silicon Chip electronics at Mona Vale. They answer emails and have an errata section. I don't think they are too happy with telphine calls as they like to publish the answers. Look at their web site first.

[Celica_73]

Yes it is a Silcon Chip project but if you look on the web site there are thousonds of unanswered questions so don't think the answer to often plus already contacted Silcon Chip and John Clarke (the designer of the circuit) and think it the Dizzy I'm more after what should be the output of one of these dizzies.

Cheers

[thechuckster]

what is the air-gap between the VR sensor and toothed wheel?

from memory it's quite small - but someone with a manual for 21R powered car should be able to provide the number

[VA61DETT]

Hi,

I would definitely be looking at the reluctor being the problem,
The gap from toothed wheel to pickup should be about 1mm.
Check the resistance of the magnetic pickup, it should be fairly low, say less then 100 Ohms (from memory).
They should give out over 5v peak when running (sharp AC pulse).
If need be remove the dizzy, turn by hand and feel for the magnetic 'cogging' from the thoothed wheel.
You can also attach an led direct to the pickup wires, there should be enough grunt to make it flash if you spin it by hand (or use a leccy drill).

I have an old 21R floating round up at a mates place, can check it out on the weekend if you still have trouble.

[Celica_73]

Air Gap is 0.009' 21R spec say 0.008 - 0.016', so thats in spec and the coil measure to be in spec too at 145 ohms. Engine has to be spinning at 2000 rpm (dizzy 1000) for the Voltage to exceed 5 Volts which is way below the 300rpm cranking speed. dizzy is currently remove for bench testing want get it working correctly before reinstalling. Would be nice if you could see what your dizzy is putting out.

Cheer

[VA61DETT]

Hmm,
Sounds like its prolly ok.

Ill try checkout my old one on the w/end.
I also have a 5m one in the shed,
will have a squiz at that tomorrow arvo.
I think they are just about the same IGN system.

[w810sc]

One problem I had with the points to elec dizzy mod using the 21r internals was the igniter. My one didn't like high revs +6krpm on my 2T-G, it developed a missfire. I took it out and fitted a MSD 6AL-2 and Blaster SS coil to go with the 21r magnetic pick up. Fixed the problem straight away.

[thechuckster]

are you sure the jaycar/SC kit is setup for a reluctor not a hall effect sensor?

also - check your earths - the VR sensor should not be earthing in the dizzi - bring both leads from it back to the igniter and if you can, use shielded cable with the shielding earthing at the case of the igniter.

[Celica_73]

Ok did a little more investigation this afternoon found the gap wasn't 0.009' it was actually 0.014' the magnetism fooled me. Even though in tolerance i adjusted it down too 0.008' that fixed the Voltage problem.

Next problem spark false pulse both with the Dizzy triggering and the Oscillator . Spark plug was firing when every it fault like it. But when the CRO's ground lead was attached it worked fine. Disconnect the Dizzy and Oscillator worked fine without the CRO attached. In short I twisted the two wires together from the Box to the plug and fixed the problem. Later discover this is what Toyota do!

NOTE: All other wishing to use a Reluctor on the Jaycar Kit take note twisted pair is required and smaller air gap then the stock ignitor required.

Cheers thanks all for the info
Jason

[petergoudie]

I have been looking at some welder circuits and the electronics manufacturer mentioned a similar issue with false pulsing and it recommended 4 twists per inch or shielded cable. This might translate over into your kit.

[Celica_73]

For those that are not aware twisting cable helps to limit the affect of noise. Shielded twisted pair is better again. That is why I tried it.

Also a warning for those looking to bench test the kit before fitting connect the dizzy body to the battery neg terminal too as this also gives false triggers. In the car the engine and earth which earth the dizzy.

Jason

[Mos]

I don't think I've seen any toyota electonic ignition setups that don't use shielded cables for the pickups. On some it looks like it's just twisted, but in reality it's also sheilded.
Are you saying the 21R pickup cable wasn't sheilded?

[Celica_73]

I don't see the 21R cable at all I just had a look at my dad's hilux which is a 22R could see twisted pair but didn't notice a shield at all. There is defiantly no shield from the plug back to the dizzy.

I only got a dizzy and that was a task in itself to find around here only a couple of place had one and some were asking $120 for a dizzy.

Install the system in the car over the weekend and still having a few teething problems. Biggest thing is getting a trigger signal from the dizzy that the Kit will pick up at cranking speed which turned out to be slower then I expected at only 100rpm. Maybe I should try a shielded cable next.

Cheers