Mechanical fuel pump kit for the Kohler KT and Magnum twin cylinder engines. Replaces Kohler part number 52-559-01-S. That number superseded to 52-559-02 and then to the current 52-559-03-S, so a dealer may quote you either of the later numbers for the same application. FITMENT. Kohler lists this pump for the KT17 and KT19, and for the Magnum M18, M20, MV16, MV18 and MV20. M means horizontal crankshaft and MV means vertical. A NOTE ON THE MODEL NAMES. There is no Kohler K17 or K19. The K-series twins are the KT17, KT19 and KT21, and the T is part of the designation. A part offered as a K17 or K19 pump is labelled wrong. The model and spec numbers sit together on the blower housing decal. WHAT KIND OF PUMP THIS IS. Mechanical and lever-actuated, driven by the engine. It is not a vacuum or pulse pump run off crankcase pressure, which is what the small single cylinder engines of the same era often use. THE SINGLE CYLINDER ENGINES ARE DIFFERENT. The K161, K181 and M8 take one pump, and the K241 through K361 and M10 through M16 take another. This is the pump for the twins. M16 and MV16 are not the same engine and that is the easiest ordering mistake to make here. BEFORE YOU REPLACE THE PUMP. If there is gasoline in the crankcase oil, check the carburetor float and needle first. A float that has sunk or stuck holds the needle open and will fill the crankcase, and it is a more common cause than a split pump diaphragm. Kohler's own troubleshooting for these engines says to make sure fuel is reaching the carburetor and to check the lines and the pump for restrictions. WHY THEY FAIL. Ethanol in pump fuel hardens the diaphragm and the internal valves. The pattern is an engine that starts and runs for a few minutes, then starves as demand rises. A machine that has sat with fuel in the tank is the usual candidate.
- MECHANICAL FUEL PUMP KIT FOR THE KOHLER TWINS - Replaces Kohler part number 52-559-01-S, which superseded first to 52-559-02 and then to 52-559-03-S. Kohler lists this pump for the KT17, KT19 and the Magnum M18, M20, MV16, MV18 and MV20. It is a mechanical, lever-actuated pump driven off the engine, not a vacuum or pulse pump.
- IT IS KT17 AND KT19 - THERE IS NO KOHLER K17 OR K19 - The K-series twins are designated KT17, KT19 and KT21, and the T is part of the designation. A Kohler K17 or K19 does not exist, so any part offered under those names is labelled wrong. Read the model off the blower housing decal along with the spec number.
- THE SINGLE CYLINDER ENGINES TAKE A DIFFERENT PUMP - M8, and the K161 and K181, use one pump. The K241 through K361 and the M10 through M16 use another. This one is for the twins. M16 and MV16 are not the same engine, and that single digit difference is the most common wrong order on this family.
- CHECK THE FLOAT BEFORE YOU BLAME THE PUMP - If you are finding gasoline in the crankcase oil, a stuck or sinking carburetor float holding the needle open is the more common cause on these engines, and it costs nothing to check. Kohler's own troubleshooting says to confirm fuel is reaching the carburetor and to check lines and pump for restrictions.
- ETHANOL IS WHAT KILLS THESE - The diaphragm and the internal valves harden and break down on pump fuel, and the usual pattern is an engine that starts, runs a few minutes and dies as demand rises, or one that will not pull fuel uphill. If the machine has sat with fuel in it, the pump is a reasonable suspect. Verify the spec number before ordering.