Α nice tip! Thanks.

Am I right in thinking that a condenser needs to as near as possible to the points. a friend has his up by the coil.

Frequently found adjacent to the points, but as experienced in some motorcycle engines this is often a very hot place, and removing the condenser to the top frame tube has enhanced reliability.

I don't know what this has to do with points condensers but back around 2008 when gasoline spiked to $4.30 a US gallon here in the US thinking high gas prices were here to stay, I tried an experiment in my lawn mower.

I wanted to see if I could mix used motor oil with gasoline as an extender.

I ran a 10/90 mix with no ill effects. No smoke, no plug fouling, etc.

I then stepped up to a 15/85 mix and it still ran fine for awhile but after about 1 liter, the engine just quit. I pulled the plug but it was not fouled. I drained the fuel tank and fuel bowel. Filled with fresh fuel and the engine started right up. The plug was not even fouled.

My guess was some of the oil fell out of suspension and snuffed the spark out.

As to why the engine never smoked, I have no idea. Maybe because the oil and gas were mixed then ignited provided a cleaner burn.

Where engines with issues like worn rings and valve guides, oil enters the combustion chamber after the ignition has taken place and that's where the smoke comes from.

I never attempted to repeat the test. One thought was if I could agitate the fuel/oil in the tank it might keep the oil suspended. Like add a fuel pump which would send some of the mix back to the top of the tank and keep it mixed up that way.

Any ideas?

My biggest concern is carbon buildup. I blew a head gasket on my current mower and was smoking and using oil. It was in October and was trying to get all my leaves mulched by the end of the season then fix my mower in the winter. So I kept adding oil to it. Eventually I fouled the spark plug and the oil would get black as tar in no time.

So I figured I might as well break down and fix it for fear I might do irreversible damage to the engine.

Take a look at the amount of carbon buildup on the head, piston and valves!

http://s222.photobucket.com/user/turbof ... t=2&page=1

My post was triggered by bobh's - the third in this thread.
Two stroke engines without separate lube pumps need a mix of two stroke oil in the fuel to maintain sufficient lubrication. Way back this could be as much as 20 parts fuel to 1 part oil. More recently, and with major chemical developments in oils over the years, many small two strokes run 50:1. Carbon build up was a regular problem when entire exhaust systems would need de-carbonising, a messy business that included de-coking the head and piston - and straight engine oil mixed with fuel (gasoline) was prone to separate, hence the need for a good shake up. Specialist two stroke oils were in part designed to mix better. Four strokes were not designed for oil in the fuel, though upper cylinder lubricants such as Redex, though again, chemical improvements in fuels and oils generally have negated this need - though there are still several products on the market that claim wondrous things.

A migration from condensors yes, but that's just the nature of threads!

Sorry for the thread hijack but there is some ignition content at the end of my post.

This may explain why my Trabant smokes particularly worse at start up after it's been sitting for a couple of weeks. I thought some of the oil may separate over time and sink to the bottom of the tank.

I've heard some people say that the higher the oil ratio, the leaner the fuel mixture because oil doesn't burn. I once set a pan of used motor oil on fire I drained out of my Subaru just to see what it looked like! It does in fact burn.

I did run a few tanks of this 30 weight 2 cycle oil called Opti-2. It's mixed at a 100:1 ratio. I've ran it in other 2 cycle engines with no ill effects. I do believe my Trabant ran better on it than my usual 40:1 mix of non synthetic.

I'd imagine adding used motor oil to petrol would reduce the octane rating.
That would be my other concern.

Just like Britain, items in the US were rationed for the war effort during WWi and WWII.

This may not be the most patriotic thing to do but allot of people traded their stamps. Or used what they were allowed to buy for some other purpose.

A good example was kerosene (or as you guy's call it paraffin) Around here, back then, most people burned coal or wood for heat since both are plentiful in this region. So there wasn't much need for kerosene for heating.

There were some people who would rig up a second tank so their car could run on either petrol or paraffin. But I think you couldn't start a cold engine on it. So once the engine was hot, you could switch from gasoline to kerosene. Allot of tractors were setup like this.

I think the threshold is 6:1 or lower. Before they started making OHV lawnmower engines which were known as "L-head" engines, these had 6:1 C/R and could run on kerosene.

Today there is no need for it. Kerosene around here costs more than petrol. Last time I bought it, it was $3.50 a gallon compared to $2.50 a gallon for petrol. Just like diesel is always more expensive than petrol.

I buy it to put in my parts washer which is cheaper than the naphtha based stuff and doesn't stink as bad.

While we are on the subject for condensers, my Citroen seems to be running a bit rough here lately, or not as smooth as it did when I first bought it. I think it's time to do a complete tuneup which I have put off.

I have one of those resin filled Harley Davidson ignition coils that was recommended to cure hot starts in 35C weather, 8 mm plug wires, new plugs, new points and condenser.

I've got a Petronix ignition system which was intended for a fork truck which found it's way onto a Fiat 124 Spider's distributor in place of the magnetic pickup which may find it's way on my Citroen. If I can find the plastic ring of magnets.

My guess is if the ring has four magnets, I need to remove 2 of them (180 degrees apart)? Otherwise the coil will try to fire when the cylinder is halfway on it's compression stroke?

I also have one of those points assisted systems I purchased as a kit I put together. I was going to use this on my Trabant but eventually got the aftermarket system working after all.

Any of you guys using a points assisted electronic ignition? Are they just as good as a 1-2-3, Petronix or any other type of electronic ignition system?

I thought once I got the car running properly, I'd install it and see how it works.