5 replies to this topic

[campfreddy2]

Hi all
A quick & very stupid question.
If I put an unleaded head on my 998, APART from resetting the timing, is there anything I either MUST or SHOULD do?
Cheers m,dears
Col

[Dan]

If your carb is really old then it might not be compatible with unleaded either, and the same goes for all your bits of rubber fuel hose. The carb can be rebuilt with a rebuild kit which will fix it as its only the seals and rubber parts which might not like the fuel, and if the carb is really old then it makes sense to rebuild it anyway. And if your fuel hoses are really old and aren't nitrile rubber then they might get eaten by unleaded as well but again they're easy to change and swapping them every now and then makes sense. Same goes for the diaphragm in the fuel pump. All the rubber parts in the fuel system can be disolved by unleaded if they aren't nitrile rubber, but since these are all service parts which are rarely original they have more than likely already been swapped for new items which will be fine.

[Pavel]

Change the headgasket while doing it (obviously!)

[miniman5]

buy unleaded fuel for the car.....

[dklawson]

What is done in the U.K. that makes unleaded fuel agressive to the rubber in the fuel system? Over here, the no-lead gas (which is all we've had for about 20 years) is made by selectively cracking the crude to get the desired octane. We don't have additives that make it necessary to update the fuel system on older cars. What do they put in your gas?

[Dan]

Not so much the fuel, more to do with the cheap rubber they used when they could get away with it. And cheap plastics and seals. Lucas petrol injection pumps and injectors are the worst for it, almost every seal in an original unit will fail within weeks of using unleaded. And only really old Mini's will suffer from it, it was the really old carbs like the H's which were so cheaply made.