"I have begun enquiries about having na LPG conversion, and the engineer at a major installer in the area advises that one of the factors to weigh up is the quality of the fuel. He reckoned that unlike the continent, where the fuel is adapted for automotive use, most if not all of that available in the UK is simply domestic propane. A number of implications arise: Firstly the fuel is 100% propane, not, as on the continent a 60:40 propane: butane mix. Although UK fuel has a higher energy coefficient, it burns hotter and places the engine under correspondingly greater stresses. Worse, because it is not filtered as effectively as continental fuel, there have been numerous instances of component failure arising from unfiltered inpurities. In a domestic situation this isn't an issue, because the feed is from the top of the tank, leaving any impurities below, whereas, in cars, the fuel feed is from the bottom of the tank, and all the rubbish ends up in the system. The genleman advising me showed me jars full of sludge which put me in mind of the anti-smoking lobby posters about tar-filled lungs."
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Warning: Reader Bruce Purvis has come up with the following vital information to anyone considering an LPG conversion in the UK: Basically, our LPG is of inferior quality to LPG in mainland Europe:-