Impellor change on Johnson 90 hp

[trapper001]

I have a 2003 90 hp Johnson IOS 2000, 2 stroke that needs a new impellor. Is this fairly easy to repair on this model? If so, how to I do it?

 

[kenmyfam]

Re: Impellor change on Johnson 90 hp

Welcome to iboats
It is a fairly straightforward procedure, however I would strongly suggest you get a manual for your motor. You should consider the rest of the water pump while you are in there as well. You can also use the search function here to find threads on the subject.
You also mention nothing of your mechanical capabilities. It is a very easy job for some but a difficult to impossible job for others. Makes it a little harder to answer.

 

[kenmyfam]

Re: Impellor change on Johnson 90 hp

You can also find a wealth of information here

http://forums.iboats.com/showthread.php?t=299680

 

[trapper001]

Re: Impellor change on Johnson 90 hp

Well, I found some time to tackle the repair tonight. Was pretty easy. The hardest part was getting the shift rod unhooked from the shaft on the motor. Not much room to work. Had the whole thing apart in about an hour. A little puzzled how the impellor is driven. Right now it just spins freely on the main shaft. The drive shaft has a machined flat spot, and the impellor has a bronze bushing in the center with a kind of lobe built into it (unless its from wear). But it looks like my problem is the impellor was spinning on the main driveshaft and not pumping water. Anybody have a diagram on how the shaft drives the impellor. There is no place for a keyway or anything.

 

[tedious]

Re: Impellor change on Johnson 90 hp

There's a little plastic key that fits against the flat on the driveshaft and engages what looks like a lobe on the impeller - if it's missing, that's your problem, but no reason not to replace the water pump while you have it apart. There should be a new key in your water pump kit.

Tim

 

[trapper001]

Re: Impellor change on Johnson 90 hp

Thanks for the info. I will plan on putting in a new pump....

 

[Supersportster]

Re: Impellor change on Johnson 90 hp

Hey I got a quick question, as I am about to tackle the same job on my 89 90HP, just wondering how heavy the lower gear unit is and does it slide right out when you undo the bolts holding it? or stay and place and you gotta pull it out??

Thanks,

Shane

 

[kenmyfam]

Re: Impellor change on Johnson 90 hp

Hey I got a quick question, as I am about to tackle the same job on my 89 90HP, just wondering how heavy the lower gear unit is and does it slide right out when you undo the bolts holding it? or stay and place and you gotta pull it out??

Thanks,

Shane

Best thing you can do is to start a new thread on this. You will get a better response.

 

[trapper001]

Re: Impellor change on Johnson 90 hp

On mine the lower unit wasnt heavy at all. One guy can easily handle it. (Although I am a big guy at 280 pounds), but it didn't seem heavy at all. You have to remember to dosconnect the shift rod from higher up towards to motor before you take the bolts out. WHen I took the bolts off, the whole lower unit just slid down nicely. But I suppose one could "stick" and may have to be broken loose. Again mine is a 2003 model, so maybe this info isn't relevent, but just thought I would share.

 

[19racing]

Re: Impellor change on Johnson 90 hp

On mine the lower unit wasnt heavy at all. One guy can easily handle it. (Although I am a big guy at 280 pounds), but it didn't seem heavy at all. You have to remember to dosconnect the shift rod from higher up towards to motor before you take the bolts out. WHen I took the bolts off, the whole lower unit just slid down nicely. But I suppose one could "stick" and may have to be broken loose. Again mine is a 2003 model, so maybe this info isn't relevent, but just thought I would share.

what holds the shift rod in cant see but one side

 

[wilde1j]

Re: Impellor change on Johnson 90 hp

There's a plastic key (usually incl with an impeller) that goes against the flat. The key either got dropped or was never there, which certainly would cause overheating. Look at the parts on BRP Evinrude website.