New impeller, tight fit ?

[kyron4]

Last year when I replaced the impeller on my Evinrude 3hp, the old impeller fins were curled and it always started smooth and ran great. The fins on the new one were sticking straight out and fit in very tight after curling the fin into the housing. I made sure they were going the right direction and put it back together. I could barely get it started and it took alot more force to pull the rope, like both hands. If it did start it would sputter and die in a few seconds. Put the old one back in and it started on first pull, one hand and ran perfect. It is the right impeller , they are the the same size when I pull the fins out on the old one. So I put the new one into a piece of PVC pipe to compress the fins, and let it set for 8 months or so; using a drill and bolt to spin it in the pipe for a few minutes every week. I took it out and the fins still went out straght but seemed more flexable. I put it back in the motor and it seems easier to pull but haven't tried to start it yet. Is this kind of thing normal with impellers ? Did I do something wrong ? Any advice ?
-Thanks

 

[tashasdaddy]

Re: New impeller, tight fit ?

i use a little wd 30 on impellers, then put the impeller and key on the shaft, place housing over impeller,turn drive shaft clockwise, the the housing slide right over the impeller with vanes at the correct angle.

 

[F_R]

Re: New impeller, tight fit ?

Last year when I replaced the impeller on my Evinrude 3hp, the old impeller fins were curled and it always started smooth and ran great. The fins on the new one were sticking straight out and fit in very tight after curling the fin into the housing. I made sure they were going the right direction and put it back together. I could barely get it started and it took alot more force to pull the rope, like both hands. If it did start it would sputter and die in a few seconds. Put the old one back in and it started on first pull, one hand and ran perfect. It is the right impeller , they are the the same size when I pull the fins out on the old one. So I put the new one into a piece of PVC pipe to compress the fins, and let it set for 8 months or so; using a drill and bolt to spin it in the pipe for a few minutes every week. I took it out and the fins still went out straght but seemed more flexable. I put it back in the motor and it seems easier to pull but haven't tried to start it yet. Is this kind of thing normal with impellers ? Did I do something wrong ? Any advice ?
-Thanks

They are supposed to stick out straight. Was it a Sierra Marine impeller? Sierra made a bunch of impellers awhile back that were too thick. In fact, they are almost notorious. If you got one of those, being too thick they are squeezed between the pump housing and plate, causing a lot of drag. Sometimes they don't even pump. Some people have reduced the thickness with a sander. Of course, get it too thin and it won't work either.

 

[ENSIGN]

Re: New impeller, tight fit ?

Another good reason to use OEM parts!

 

[kyron4]

Re: New impeller, tight fit ?

I got it from NAPA auto parts here in town. Don't remember the make.

 

[F_R]

Re: New impeller, tight fit ?

I got it from NAPA auto parts here in town. Don't remember the make.

NAPA sells Sierra

 

[kyron4]

Re: New impeller, tight fit ?

It didn't seem tight top to bottom just stiff on the fins. How will I know if it works or not ? -Thanks

 

[jasper60103]

Re: New impeller, tight fit ?

It didn't seem tight top to bottom just stiff on the fins. How will I know if it works or not ? -Thanks

kyron4,
worrying about this for 8+ months sounds a little excessive. I would drop an OEM impeller in there for peace of mind and call it done.

 

[1946Zephyr]

Re: New impeller, tight fit ?

Another good reason to use OEM parts!

I totally agree. So far, I have never had trouble with OEM parts. Napa parts have been questionable many times, as I have experienced. I'm about to put an impeller on a 3hp myself.

 

[kyron4]

Re: New impeller, tight fit ?

Where the best place to get an OEM impeller without paying a forutne for shipping ? -Thanks

 

[bktheking]

Re: New impeller, tight fit ?

Where the best place to get an OEM impeller without paying a forutne for shipping ? -Thanks

That all depends where you live? Many on this board could point you in the right direction with that info.

Cheers

 

[1946Zephyr]

Re: New impeller, tight fit ?

Go to your local Evinrude/Johnson dealor if you want to get it without paying shipping. You can buy it here too, or try:

Seaway Marine
Engine Blade and Prop.
Vintageoutboard.com

If these 5 places can't help you, then someone can provide a few more sources, but I think you'll be able to get it at the first stop.

 

[F_R]

Re: New impeller, tight fit ?

Go to your local Evinrude/Johnson dealor if you want to get it without paying shipping. You can buy it here too, or try:

Seaway Marine
Engine Blade and Prop.
Vintageoutboard.com

If these 5 places can't help you, then someone can provide a few more sources, but I think you'll be able to get it at the first stop.

With gas prices going up again, shipping might be a bargain if the nearest dealer is 100 miles away. Somebody said, depends on where you live.

 

[kyron4]

Re: New impeller, tight fit ?

No need now. I couldn't stand it anymore so I heated up the garage and filled my test tank up and fired 'er up. Started on the second pull and ran fine. Had a nice steady stream of water comeing out of both sides of the exhaust relief vent. Ran it for 5 mins or so at 3/4 throttle and I could still touch the head all over, in fact it was only warm. so I guess I got lucky, now I'm all set for spring. -Thanks