TwinSpark wont start.

[Alan Hopla]

Dear Gurus looking for some help here.

The TwinSpark did a water pump the other week.
I have removed radiator assembly, crankshaft front pulley, and water pump.
Fitted new water pump.
Found the crankshaft pulley was damaged, (splitting at the key way), so have replaced the pulley.

Car all back together but will not start, (started just fine 1st time every time before I did this).
I have spark and pretty sure I have fuel, but the best I can get is one cough.

All I can think is some issue with the crank angle sensor.
First are all crank pulleys the same.
Is there any adjustment for the sensor. I removed the sensor today, and it looks like it just pins in place.

Any ideas greatly appreciated. What else might I have disturbed?
Alan.

[Alan Hopla]

Spent the best part of a day on the weekend checking all and sundry.
Found a specification for the air gap between the crankshaft pulley and the pick up of 1mm +/- 0.5mm.
Also found a spec of 1.5V output from the sensor when cranking.

My gap was 1.3mm with 1.2V output.

The sensor looks to be non-adjustable, so I machined the face of the mounting bracket to close the gap down to 1mm.
Then got ~1.5V when cranking and after a bit of a struggle the engine fired.
I think it may have been a bit flooded at first as it would sort of fire but fail to catch, but once it started I have had no more problems getting it started.

The next job was to fix the blowing exhaust.
Oops not a loose joint but a blown out centre muffler, so fitted the spare.

Now just one more job, (I hope).
Discovered the fuel tank is weeping through a very small crack in the bottom.
So this weekend its, pump it dry and fit the spare tank.

Should even have it running for the motokhana.

Maybe now I'll get some time to work on the track car.

[Paul Gulliver]

Patience  is a virtue

[Alan Hopla]

Paul,

I guess the upside was that James rolled his ankle the other week so couldn't drive it anyway as the clutch foot has been a bit sore.

Also I've done a couple of hundred k's in the car and it looks like it isn't using coolant, so at least he didn't do too much damage.

[Tristan Atkins]

Hey Paul and Alan,

On the way back to my job in QLD my car decided that it enjoyed itself too much in VIC and decided to break down just short of the border. It would crank but no spark. I got a tow truck to the local Alfa dealer who discovered two things: The two plugs from the ECU to the coils has some slight corrosion and the crank angle sensor was dirty.

I had previously re-tensioned the alternator belt and I had used some belt grip spray which also went over the crank angle sensor.

Long story short, I think this sensor is quite "sensitive" and its worth keeping it clean.

[Paul Gulliver]

I think this sensor is quite "sensitive

I think that is the Twin sparks underbelly