How to substitute leaded gasoline

I have a gas powered scarifying rake or vertical mower(Vertikutierer in German) that apparently needs leaded gas. Anyone know where I can get a substitute or does it really matter if I just use unleaded gas?

How old is this vertikutierer? I had to bring my lawnmower to the shop a few weeks ago and he said only use unleaded gas with it and to use the highest grade possible.

I know it has something to do about boosting the octane level. I think I will just try it with reg.gas and see what happens.

@kitkat atleast 20+

You could try using this stuff. Liqui-Moly Blei-Ersatz. I have no idea if it works but you can get it off Amazon.

You need a lead substitute petrol additive. All car accessory/motor factors will sell it. Stops the valve seats burning out on certain pre-unleaded era engines. That stuff linked above from Allershausen is ideal.

Hi ho hi ho off to the gas station I go...

A few drops of diesel will also work. My grandfather kept his leaded gas guzzling truck long after they stopped selling leaded gas by putting a few drops of diesel in with every fillerup.

Yeah it's pretty common, it a clear red liquid you should be able to get it at a petrol station.

Could a sworn your German (ah so close).

Allready got the stuff anyways and thank u everyone.

My grandparents used the highest octane gas available (93 US, so probably 98 over here) to run her 1970 Ford T-bird all the way to 1990. I don't know how well it ran compared to back before "ethyl" was banned in the US, and sadly they're not around to ask, but it might be worth a try.