I’ve spent £300 and ruined my bus….Please Help

Hello all,

I hope you are all loving life in your bus in the sun at the moment. However, for those that are not…I need help.

Since I got my late bay, I have had everyone that I spoke to about it telling me to upgrade to electronic points. I was very happy with everything generally when running traditional points. I was comfortable with tinkering with them, setting the timing and keeping it running.

THEN….being honest, peer pressure got to me. The hype was too great; the promise of more power, less maintenance and better economy sucked me right in. Now it is the summer and I am in the bus most weekends, I thought that I would like a bit of that so I bought a Petronix 3 system with compatible flame thrower coil and uprated flame thrower HT leads.

My bus now drives like crap.

Economy is better. Top speed is remarkably better but, at low speeds, it chugs, it backfires and hasn’t got the power to pull the wings off a daddy long-legs. What have I done wrong?

The system has been in for about a month and I have fettled around with timing etc relentlessly and nothing is improving.

Any advice would be greatly greatly appreciated. Please help.

 

Put the old stuff back in. You won't be the first!

Enjoy the summer, revisit it in the Autumn when you've a bit more time

 

Check you have at least 12v at the coil. The blurb says this is a MINIMUM.

 

Is points and condenser better than electronic ignition, if its not a 009 and maybe a 034 ? with vac advance?

 

Shouldn't be any different, the main advantage of the electronic is that it doesn't wear like points so you don't need to ever check and reset the timing. Theoretically that should lead to better overall performance. SVDA is always better unless you're on the drag strip revving the nuts.

 

Ok I'm smiling again, thanks

 

^this. Apart from less maintenance, basic electronic ignition shouldn't really make any difference to performance or economy unless your existing system was pretty crap.

Timing set correctly (start with 7.5* static)? Don't fiddle with it. Don't "adjust" stuff using the ignition timing. Check the firing order's correct and the leads are properly seated as a starting point.

Personally, I wouldn't have chosen the Pertronix kit. Is doesn't seem to have a good reputation. Can you send it back?

I don't disbelieve @Zed with the 12V min supply thing, but that is fairly ridiculous. The coil voltage can easily dip below 12V when cranking the engine.

 

Could it be tracking at the coil terminals , take a look in the dark and see if you can see sparks tracking across from the coil terminals and indeed anywhere else under the bonnet , the symptoms you describe seem to fit the bill for this to me especially as youve fitted a new coil .

 

It's a bit of a weird thing.
"Requires 12-14 volts . Must use suppression core ignition wires . Not for use with cD or multiple spark systems . lobe sensor design triggers off the point cam or reluctor and does not require a magnet sleeve"

 

Odd.

For the same money, you can have a basic 123.

 

But the 123 is made in Europe, so good ol boys cant use it because it isnt made in the USA.


No you havent ruined your bus, just one M8 nut and pull two wires off and a vacuum hose, then swap back the old distributor ..


Did you also buy the Chinese distributor that goes with the (Chinese ? ) Pertronix electronic module fitted in it. It could just be mechanical crap plus electronic crap anyway.

The Pertronix Ignitor 3 is more sensitive to wobbles on the supply voltage to the coil, it affects the dwell angle and therefore the ignition timing...

On a Type 4 engine with skinny wires from the ignition switch to the coil, you see about twice the voltage drop as the coil charges with energy compared with a Type 1 which came with thicker wiring. There is also often an electric Facet fuel pump blipping away bouncing the supply voltage at the coil.



Backfires however with electronic ignition are quite often misfires - a coil with flashover, or a distributor cap flashing over, ignition leads flashing over, electronic module suddenly decides your engine has stopped, then decides it hasnt stopped so it fires again..



If it chugs however - timing at idle may be off. Because if the idle speed is set to over 1000 rpm (think choke on at first) , when you think you set the timing to 7.5 degrees, you actually have a bit of centrifugal advance added on. Then as the engine speed slows, the timing advance reduces to more like 0 degrees. Then the engine chugs at low speed, but if you nurse it up to speed its only a little bit slower than when properly timed. .


Basically a simple electronic ignition like the Pertronix system only works as well as a "good" contact breaker and condenser in an "as new" distributor, on the day that the timing was set up.
A few thousand miles down the road and the electronic unit should still be working better, as the contact breaker wears , and the condenser suffers from quality control.

Now that stupid prices are being asked for Pertronix setups, the 123 becomes a better deal, you eliminate the problems of points, then you eliminate the problems of having the newer "adaptive dwell" heat-sensitive electronic modules in old style distributors.

 

A 123 would have been a better choice, however if you are stuck with the Pertronix set up I would first swap the coil for the original if it has the same primary resistance. Like the Accrapuspark stuff @snotty also has a pile of Flamethrower coils at the base of his fence. They can be temperamental.

 

Have you read up about this particular pertronix ignitor? It's a weird one with double sparks "5x as much spark power", no magnetic collar etc etc. You can't use normal HT leads with it, I doubt you can use a stock coil. Unfortunately I think the OP didn't really comprehend what he was getting into here and that basically none of that was necessary or would provide any improvement over a cheaper ignitor or... points. Oops.

 

oh dear sounds like an expensive unreliable pile of junk. I recon I would get it packed up & sent back if it was me.

 

Put the old stuff back on, and buy spares of it for the future.

 

Which one are you looking at?

 

I see.. theres the Ignitor II that they sell that are inside the distributor which is what I was talking about ( sorry) which I am beginning to suspect are just the stars and stripes glued to a module that also came from the same factory as all the others..

There is also a Pertronix III electronic box which uses the very low resistance coils 0.32 ohms from more modern electronic ignitions and so will drag big current >30 amps in spikes from the power supply.

That would need direct battery connection through a relay and fuse given the state of our ignition switch wiring in general.

Because it uses that low resistance and lower inductance coil it can "charge" and fire the ignition system much faster. So its advantage is either for multi spark ( which they dont do ) or very high speed engines or more cylinders than 4.

It takes its timing from the lobes on the distributor cam so must be using a reluctor sensor (metal detector) to get the signal. Because those lobes are fairly "gentle", a small change in the distance between the shaft and the sensor will alter the timing.. a rattly distributor will be just as bad or may be worse with replacing the spring pressure and drag of points with a "free flying" sensor.


It also can use components that are intelligent in themselves so are much harder to blow up , just like the 123.

The 123 can do multispark too but I think its more of a compromise using a 3 to 4 ohm coil, there isnt enough time to rebuild the magnetic field at 4 amps ..

 

ignitor III

 

did you buy the right pertronix version for your distributor? ie you havent put an 009 dizzy pertronix in a vac advance dizzy have you?

 

Thanks. Doubt I can send it back. The HT leads were the self assembly sort. What system does get a good write-up?