leaded petrol and LPG, 504 estate (X reg)

[geoffgeoff]

I'm having problems sourcing leaded petrol. If I use unleaded, is there a recommended additive I could use? Could one solution be to convert to LPG and does anyone have experience of this?

[Admin]

Hi Geoff and welcome to the forum. I know that smb here runs his 504 Ti on unleaded with no problems at all. It's normally only while the valves are bedding in that unleaded causes a problem so you should be fine. I was concerned about my ZS as the cylinderhead and valves were brand new so potentially vulnerable but I don't think this applies to you.

[Piston Broke]

You should be fine mate. Most engines are either iron head or alloy head with steel inserts, so valve seat recession is actually pretty rare these days. If you've got no ignition timing issues with pinking then don't sweat it.

[504V6Ti]

You'll be Ok running with unleaded, full stop. Do not bother with any additives. You have the 2.0l carb haven't you? You could replace the hose connections and adjust the ignition timing but that's about it. I have never bothered to do these myself and have no problems to report after many thousands miles.

[504gld]

Hi well I'm the one (driving 504 diesel of course) who says otherwise! We seem to have this conversation about VSR quite a bit and I'm in the other courner on this one.

The 504 carby engines would run on the old 2* without problems, but of course this was a leaded fuel.

OK whilst Peugeot in the UK really wont be concerned about a 504 anymore, in other parts of the world, e.g. Nigeria where they are still everyday vehicles, Peugeot is concerned.

this link is to a Peugeot document regarding VSR and switches to unleaded fuels in Nigeria. Peugeot say all 404, 504 and J5 before 1986 are effected. Peugeot say a Potassium additive is necessary.

Now VSR occurs especially if the engine is used hard, gets very hot or working extra hard e.g. towing.

For the sake of a couple of quid my vote goes to a bottle of additive like Valvemaster. I used this for 12000 miles in one year in my Morris 1000, and I drove that to the max in my slightly younger years. The A series is well recorded as being VSR prone.

Another Austrialian site says "The withdrawal of lead replacement fuel will also affect most European and Australian high performance models from the 1960s and early 70s, and every US V8 prior to the mid-70s. European models affected include all Mercedes-Benz models prior to mid-1976 and most models prior to the early 1980s; virtually every Peugeot prior to the 505 and every Renault prior to the Fuego" This is backed up by the Austrialian Fuel authority who say 604 is ok as their models were V6, all 504 need help! and 505 ok.




that doc is www.cleanairnet.org/ssa/1414/articles-36224_effects_pdf.pdf

[504V6Ti]

The link points to a document about Peugeot vehicles built in Nigeria where the engines have a different configuration. They do not match the specifications of European cars. I, for one, would not base my judgment about leaded/unleaded fuel use in an older car on a document talking about cars for the African market.

Luckily, the document is well enough written to specify that:
1) tests run in Europe showed showed only 1% of cars got affected by VSR.
2) nothing to worry about for cars used under "normal" conditions

Now, as far as adding potassium to the fuel is concerned, I'd advise everybody to do their studies before trying it. Personally, I've heard horror stories...

[504gld]

There are a lot of cars in Europe....1% could just be the wrong car to own. After all, I think we'll all make our own choices. If the 104 comes my way its on the Valvemaster....

[Admin]

504gld said:

If the 104 comes my way its on the Valvemaster....

What 104?

[edit] oh THAT 104. Purple eh!

[geoffgeoff]

Thank you for all your very helpful advice. I have followed the majority view and am now running on unleaded without any additives. So far - 100 miles - so good!