Moderated Discussion Areas
  ContinuousWave: Whaler Repairs/Mods
  Impeller question?

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   Impeller question?
hauptjm posted 08-09-2001 03:44 PM ET (US)   Profile for hauptjm  
Has anyone changed an impeller on a 90's Johnson? I have a '95 Oceanrunner 150 and was wondering what your time investment was in the project. Does it require dropping the lower unit off? If so, how difficult was it to reattach the drive shaft and linkage? I appreciate any opinions.
L A posted 08-09-2001 04:00 PM ET (US)     Profile for L A  Send Email to L A     
I just changed the impeller on a 90 225 Evinrude on my Aquasport. Not too big of a Job but be careful taking bolts out of lower unit, don't force it if there is corrosion, I had one stainless bolt that was tight due to aluminum corrosion. The shift linkage has a small bolt with a screw slot in the head right at the base of block in front of motor. Pull off the cover and you should see it, I used extension with swivel to loosen the bolt, it backed out far enough to release linkage, don't drop it! Replace impeller with key, reassemble and use anti seize or marine grease on bolts. Sometimes you may have to use emery cloth on driveshaft if there is any rust so you can get impeller off. good luck
L A posted 08-09-2001 04:04 PM ET (US)     Profile for L A  Send Email to L A     
Sorry for not answering all your questions, plan an afternoon for the job, the lower unit has to come off. The trim tab on lower unit has to come off first to get to all the lower unit bolts. Check the price for a kit with new housing versus just impeller repair kit. I just replace impeller, housing was fine, some people replace entire unit.
hauptjm posted 08-09-2001 04:07 PM ET (US)     Profile for hauptjm    
Thanks LA! I planned on blocking the lower unit as I dropped it. Guess I have no choice but to remove. You didn't say how long it took. I'm curious because time is short with a wife, two year old and another "bun in the oven".
L A posted 08-09-2001 04:31 PM ET (US)     Profile for L A  Send Email to L A     
I think a couple of hours if you had all the parts and no snags, etc. You really don't have any choice about fully removing the lower unit, the impeller has to come off the shaft and the new one goes back on the same way, so you have to access top of shaft. Watch out angle of shift rod going back in, I messed around getting it to line back up in the housing, if I remember it angles toward the front of engine to make it back up into the bracket with the bolt that secures it.
hauptjm posted 08-09-2001 04:51 PM ET (US)     Profile for hauptjm    
Thanks again, good stuff!
Clark Roberts posted 08-09-2001 05:53 PM ET (US)     Profile for Clark Roberts  Send Email to Clark Roberts     
James, LA gives good advice.. here's some more! Good idea to read service manual since you've not replaced a water pump/impeller before and also get some help from someone who has. Once you've done it, the mistery is gone, but things can get touchy if you haven't done it... two things come to mind that may help you out: 1>put lower unit in fwd or reverse so that when you are trying to alighn the spline on drive shaft to socket in crank you can spin prop shaft slowly (drive shaft will turn since in gear) and as you push and turn shaft it will mesh and slide into place. If in neutral you must turn crank via flywheel to mesh spline! ; 2> put vaseline on the new impeller once its in place and keyed and slide the housing down the drive shaft... press the housing hard against the new impeller (impeller vanes will be extended) and slowly turn the drive shaft clockwise! This will "spin" the new impeller vanes inside the housing like magic. Now just replace bolts etc.. Isn't vaseline great stuff! Happy Whalin'.. Clark.. Spruce Creek Navy
hauptjm posted 08-10-2001 09:15 AM ET (US)     Profile for hauptjm    
Thank y'all for the tips. Clark, you're right, I'm going to "borrow" a friend that's experienced for the first one.
Ferdinando posted 08-10-2001 06:38 PM ET (US)     Profile for Ferdinando  Send Email to Ferdinando     
Clark / Jim:

Heres a loaded question, I have a 90 hp 1998
Johnson on a 17' Montauk. I have 173 hrs on the engine since new. Although it's always used in salt water, It's always flushed after each use (at least 10 minutes).No brakish water use or any other type of abuse.

What would be your best ballpark figure on when to change the impeller???????.

I had a 1986 70hp Evinrude purchased new and I changed the impeller for the first time in 1991, the impeller still looked new!!!!!!!

Appreciate your input, Thks, Fred

Clark Roberts posted 08-10-2001 11:22 PM ET (US)     Profile for Clark Roberts  Send Email to Clark Roberts     
Fred, as far as the impeller is concerned, every 200hrs or two years may be a good benchmark. however, I change impellers each year (on my birthday, the only way I can keep track) not solely because of impeller wear but mainly because I want to make sure the thing comes apart easily. You see, each time you take that lower unit off, you grease up the spline and the threads on all those bolts... once a spline freezes up because of corrosion (just time will harden up the grease like cement) etc, it's all over and you must engage in some major surgery and lots of heat to get it off if at all!!!! Maybe each year is too frequently but it's so easy that I do it! I also change plugs and lower unit oil while I'm at it... Others may have different schedules but the important thing is to have a maintenance schedule! Waiting until the hot horn goes off and the spline if frozen into the crank is not what I would recommend... happy Whalin'... Clark... Spruce Creek Navy
Clark Roberts posted 08-10-2001 11:27 PM ET (US)     Profile for Clark Roberts  Send Email to Clark Roberts     
PS> where I live the boating season is 12 months a year so I usually put lots more than 200 hrs. on an engine each year! But the impeller can "take a set" when motor is layed up and this can be as detremental as lots of use... just something else to consider
Whalerdan posted 08-13-2001 10:36 AM ET (US)     Profile for Whalerdan  Send Email to Whalerdan     
One more thing resist the temtation to spin the shift linkage shaft. It will messup the adjustment.
hauptjm posted 08-13-2001 11:14 AM ET (US)     Profile for hauptjm    
My friends say at least every two years. Personally, I have never had one fail. That doesn't mean it won't happen. I agree with Clark, we should try to have a schedule for maintenance. I try to keep one on my car, so it only makes sense to do it on my boat. Besides, I've never been left out at sea by my Chevrolet!

Back on point: this is my first try to do it myself. I've done alot to my cars and boats, just not this. Some time back lhg suggested that he feels confident in his vessels because of all the work he does personally. I could not agree more. When I repair, install or whatever on my boat, I feel 100% better that the job was done right. Mostly because it takes me so damn long to do it, I feel I've covered all the needs. I really try to do all work better than original manufacturer quality. No one cares for your boat more than you.

Cal posted 08-14-2001 12:41 AM ET (US)     Profile for Cal  Send Email to Cal     
From my '92 Evinrude 150 impeller exchange here are a few ideas to add to the previous good suggestions.

There is hole, just below the fuel line barb, in the lower cover that allows access to the shift rod bolt. I needed a 12" 1/4" drive extention (or 2 X 6")with a 3/8" socket.

I had a tough time getting the cover over the new impeller so I tightly wrapped it with light line until the vanes flexed enought to fit partially inside the cover.

The cover bolts were stiff and the book calls for a torque wrench for even sealing.

The bottom end is pretty heavy and would be a challange to reinstall without a second pair of hand to start the bolts.

I bought the whole kit online for about $35.

Clark Roberts posted 08-14-2001 08:16 AM ET (US)     Profile for Clark Roberts  Send Email to Clark Roberts     
CAl, see my comments re:vaseline above... This works like magic and you will be surprised at how simple it is to get those vanes "spun" into the housing! Happy Whalin'... Clark .. The Old Man and the sea
Cal posted 08-15-2001 12:45 AM ET (US)     Profile for Cal  Send Email to Cal     
Thanks Clark, I had used some bearing grease on the vanes but they weren't going in for me. Next time I will try vaseline.

It was a learning experience and will go a lot faster next time.


Clark Roberts posted 08-15-2001 07:15 AM ET (US)     Profile for Clark Roberts  Send Email to Clark Roberts     
Cal, you must press the housing down on those extended vanes and simultaneously turn the drive shaft clockwise. It's the turning of the shaft that causes the vanes to "spin" into the housing... it works every time and will work with any kind of grease! I use vaseline on all gaskets, rubber parts etc because it's inert and won't attack and/or disolve anything... modern greased can have chemical additives etc which could do damage!
Happy Whalin' .. Clark.. The Old Man
Whalerdan posted 08-15-2001 07:34 AM ET (US)     Profile for Whalerdan  Send Email to Whalerdan     
On our aircraft we use vaseline on all O-ring installations. It helps to keep from cutting the ring when the two parts go together.

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.