torek, 06. marec 2012

Replacing impeller on yamaha F80 outborad engine

Impeller is a critical part in marine engines. It is the main component of the water pump and is used to pump fresh and cold water to the engine cooling system. That is why it is so important to check its condition very often. If your impeller is broken you may permanently damage your engine because of overheating your boat engine. There is an unwritten rule that says that you should replace your impeller on your boat engine every two years even if it's in good condition.

  1. First we unscrew the four screws that are visible on the side of the engines heel.
  2. Next we have to remove the rubber plugin on the narrow end of the engine and we unscrew the zinc protector that is located above the propeler
  3. We remove the zinc protector and we unscrew the number 12 bolt from the bottom side
  4. Next we have to remove the engine heel and remove it from the boat engine
  5. We have to buy original Yamaha impeller
  6. Next we remove the four bolts from the water pump housing
  7. We use a hammer to gently tap on the water pump housing to remove it (Warning: Handle with care!!)
  8. What we see in front of us is a boat engine shaft with a small rubber propeler attached to it => that is impeller
  9. We take the impeller of the shaft (if it won't go of we use a knife on it)
  10. We put our newly bought original impeller on the shaft and put a small metal plugin inside a little hole in the shaft to hold the impeller in place
  11. We put the water pump housing back in place and we have to wrap the impeller blades to fit inside the water pump housing
  12. The blades must be slightly bent inside the water pump housing
  13. We than screw everything back in its place, and before you put your screws in you might consider lubricating them with a water resistant lubricant
You can see/read a complete tutorial in my previous blog (slovene version)  following this link: