Process for the prevention or reduction of deposits in carburetors, injection devices and similar devices of engines

Process for the prevention or reduction of deposits in carburetors, injection devices or similar devices of engines, which are operated with alcohol fuels comprising 99.9 to 75 Vol.-% methanol, ethanol or a mixture thereof and at least one corrosion inhibitor, in combination with lubricants, which are suitable for engines operated with hydrocarbon fuels, characterized in that one or several polyol ethers are added to the alcohol fuels in a quantity of 15 ppm to 1 weight-%, whereby the polyol ether(s) has (have) the general formula ##STR11## wherein R is H, linear or branched C.sub.1 -C.sub.20 -alkyl, C.sub.1 -C.sub.20 -alkenyl, polyunsaturated C.sub.1 -C.sub.20 -alkyl, C.sub.1 -C.sub.20 -cycloalkyl, mono- or bicyclo-C.sub.6 -C.sub.14 -aryl, unsubstituted or substituted;

• wherein R.sub.1 is H, C.sub.1 -C.sub.8 -alkyl, unsubstituted or substituted aryl;
• wherein R.sub.2 is H, C.sub.1 -C.sub.8 -alkyl, unsubstituted or substituted aryl and wherein R.sub.3 is Or.sub.5, SR.sub.5, N(R.sub.5).sub.2, wherein R.sub.5 is H, linear or branched C.sub.1 -C.sub.20 -alkyl, C.sub.1 -C.sub.20 -cycloalkyl, mono- and bicyclo-C.sub.6 -C.sub.14 -aryl, unsubstituted or substituted;
• or ##STR12## wherein R.sub.6 is H, a linear or branched, saturated or unsaturated C.sub.1 -C.sub.20 alkyl- and mono- or bicycloalkyl group or a substituted or unsubstituted mono- or bicycloaryl group, an unsubstituted or substituted amino group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted thioether group;
• wherein R.sub.7 is a linear, branched, saturated or unsaturated alkyl group, or ##STR13## wherein R.sub.8 is R.sub.6 and the C.dbd.O groups are not directly interconnected or are interconnected by unsubstituted or substituted saturated or unsaturated methylene bridges consisting of 2-5 methylene groups,
• or phosphoric esters or thiophosphoric esters;
• or alkylethylene diamine tetra acetic acid ester, amide or imide
• whereby m of the polyether molecule exclusively is 2 or 3 or 4 or combinations of these numbers, and
• n is 2-200.