New impeller

[tmcalavy]

Hey all,<br />Love this site/board. I need to replace my water impeller on my Merc 500 50 hp (74 model I think). Now I can take it to the boat guy and spend about $75, or I can start learning how to do this stuffy myself since I'm pretty handy (do all my truck/auto maintenance, etc.). However, my Clymer's manual is really vague. Is this an easy job on this engine? I think I can figure out how to drop the lower unit, and once I get that done I can probably worry out how to do the pump and impeller. But how hard is it to get the lower unit back in/up? Is there any special alignment, special tools, etc. involved? Can one big ole boy do it alone? Just too many questions. Wish I had a better manual.

 

[lonewolf5347]

Re: New impeller

THE HARDEST THING IS GETTING THE UNIT BACK UP.THE IMPELLER TO CHANGE IS EASY JUST NOTE ROTATION OF FIN'S HAVE TO GO BACK IN SAME DIRECTION.NO SPECIAL TOOL TO REINSTALL .

 

[tmcalavy]

Re: New impeller

Thanks for the reply. "hardest thing is getting the lower unit back up." Do you mean physically lifting it back up and holding it until you can secure it? Or is it hard to realign it right while wrestling with it? Any further explanation would be greatly appreciated.

 

[SeaDawg]

Re: New impeller

It will take you a couple of hours the first time, and then only 15 or 20 minutes if you do it again. Provided all the bolts come out easily, you don't drop anything, etc.

 

[bill giffear]

Re: New impeller

TIM MC, new water pump will cost about $75.00,last one I did had it's own instructions/it was bought at evinrude dealer,make sure water tube lines up no big deal..<br />bill

 

[tmcalavy]

Re: New impeller

Thanks guys,<br />I'm almost convinced to dive into this tomorrow in the garage. Better for the motor to be up or down? Thanks again.

 

[alcan]

Re: New impeller

Hi Tim <br />It's usually best to have the motor up. You will also have to make sure the splines on the shift shaft line up correctly. One thing us big ole boys have to remember is this is a thinking game not a physical one. Have fun and good luck.

 

[lonewolf5347]

Re: New impeller

REMEMBER CHECK TO SEE UNDER THE TRIM TAB. THAT THERE IS NOT A HIDDEN BOLT.DISCONECT THE SHIFT ROD,MARK THE TRIM TAB TO GO BACK THE SAME WAY.YOU MAVE HAVE TO THROW IT INTO GEAR WHEN REINSTALLING TO LINE UP SPLINE ON SHAFT.ABOUT A 30 MIN. JOB.GOOD LUCK

 

[keg]

Re: New impeller

Hey Tim MC I just did one on a merc. 35hp if it is pretty much the same it was pretty easy. You have two bolts on the botton of the lower unit, one under the trim tab (that's the fin like thing on the bottom) and one you can see, you also have to remove the 2 side bolts where the lower unit hooks onto the motor. I have heard of guys having trouble dropping the lower unit, but mine fell right off. When you get it off you will see the drive shaft (one inch thick rod with splines on top) there was also a plastic spacer and a cone washer on the top of mine, at the bottom of the drive shaft there is a plastic housing with four nuts on it. Take that off an "Violla" there is the impeller. The veins on it will probably be wasted so it will come right off. I just forced my impeller back on It's a little oversized so force the new one back in turning clockwise. When you push the lower unit back on have someone jiggle the top of the motor alittle so the splines line up and make sure your shift rod (smaller rod that fits onto another rod with splines) is lined up. The way to check that is when you have the lower unit in place shift the trans. into foward and turn the prop it should just move clockwise then go into reverse and it should just move counter clockwise. Tighten the bolts back up put the water to it and make sure your spitting water out of the tell tale and your done. Hope this helps and I hope it is pretty much the same as mine or I just wasted time typing all this and look like an idiot. Keg