Can a peogeot 106 run on vegetable oil?

Answer 1

yes, BUT...

If the car has a Lucas injection pump (most built up to 1999) it is highly likely that the pump will self-destruct after a few hundred miles or less. This is due to the internal use of diesel for lubrication. Vege oil is too viscous for the job. Stick to a 30% mix of oil and DERV at most.

Cars fitted with Bosch pumps (most assembled after 1999) can run 100% SVO or WVO happily (in summer, see notes below)

Caveats:

1: Cold oil is very viscous and may block the filter. In extreme cold it may wax up (WVO is very prone to this at freezing or below). Fit a heat exchanger on your fuel line and/or electric filter/fuel heaters before the filter (the 106 fuel filter mount is NOT water-heated, it just looks that way)

2: Oil has a slower flame front than diesel. This will exacerbate any smoking due to leaky injectors or retarded injection (blue smoke) especially when cold. If this happens, get your injectors serviced. My car was _VERY_ smoky when cold and mostly cured when this was done. Injection timing is not adjustable on a Bosch fuel pump.

3: Vege oil or biodiesel are very likely to loosen any crud in the fuel tank and cause it to be sucked into the tank filter or onwards into the main fuel filter. The tank filter is fairly easily cleaned if you're mechanically minded (GET A HAYNES MANUAL). Add a coarse mesh filter in the engine bay in front of any heaters and check it for large-scale contamination regularly.

Replacement fuel filters are 12 pounds each. Get one and keep it in the car.

4: Mineral lubricating oil has a tendency to gel after some time on Vege oil. If this happens your engine will be destroyed. Increase oil change frequency to ~5000 miles or change to a plant-based oil such as "Plantomot" (Plantomot & 8000 mile changes is cheaper than using standard oil and shorter changes anyway

5: Optional: I've added a cheap electric diaphragm pump to the fuel line to keep supply pressure up for cold weather starting. Am considering other options. Put this _after_ any inline mesh filters.

6: Important: Make sure your exhaust system is hanging neutrally on the rubbers when the engine's stopped. Also check the engine-downpipe attachment as this point is prone to breaking if the exhaust is incorrectly fitted (It's a well-known problem on 106 diesels, but most outfits don't realise the criticality of hanging the exhaust "just right" as a preventative measure)

Whys: Running on vege oil has a much rougher idle than normal diesel and the added movement/flex will eventually *snap* the downpipe just below the downpipe-manifold attachment if the downpipe engine attachment is broken and/or the rest of the exhaust is in sub-standard condition. This happened to me while analysing the reasons for repeated downpipe attachment breakage. The car is LOUD in this condition and hot exhaust gasses in the engine bay may be damaging or gas the driver/passengers.

Other things to consider:

Magnetic Sump plug, Flexmag or similar on the oil filter to catch any engine swarf (these are old engines, you want to minimise any further wear).

Insulated fuel/injector lines (keep oil going back to the tank as hot as possible), cold oil return bypass to minimise fuel pump load until things are up to temperature.

Insulated exhaust (bandage, etc) back to the catalyst unit - this will reduce noise, engine bay heat and aloow the cayalst to "light up" more quickly, reducing smoke when cold.

Insulating the fuel tank is an interesting proposition for cold weather running/starting, but a lot of work. I am exploring the possibilities of this and/or a wabach-style water heater

Change the feed fuel line from the filter to the pump. It's semi-rigid and has a tendency to crack/leak - this means air in the fuel and very rough idling/difficult starting when cold.

Most importantly, if you're doing any of this, have another means of transport available, especially in freezing weather. My car was unusable for 6 days last winter due to a cold snap that caught me offguard (in cold weather it's best to run 30% diesel. I wasn't doing that and the lines waxed up.).

Treat it as a project car. While it may be a daily driver and the lowered costs are worthwhile, you WILL have times when it is offroad or you're driven crazy trying to make things go.