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25HP Johnson Impeller - Big Trouble

I

itsanss

Member
So I’m in a huge mess....

Bought a new impeller for 1987 Johnson 25 HP model J25RCUR.

I took the plastic screens off the sides, loosed the shift linkage, and removed the four bolts and one nut to remove lower unit. The one thing I forgot was to remove the bushing off the end of the shift rod. I’ve pulled the lower unit down about 6” and now the lower unit won’t come down any farther OR go back up. It is STUCK bigger than Dallas. I want to slide it back up to be able to remove bushing, but I’m afraid I’ve really bit the big one here.
 
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A side note....when I try to push lower unit back up, it just moves the shift lever. It’s like the splines won’t line up or something.
 
You may need a helper. Make sure you pull the shift arm out of the way and then have someone slowly rotate the prop as you push the lower unit back into the upper. The lower unit will have to be in gear so you may need to push the linkage rod down or pull it up. Side note, if you've not put in an impeller before and it's like the ones in my JohnnyRude 150s they are STIFF. I used a heat gun to heat mine up so the splines would bend to fit into the cup.
 
Thunderyacht said:
You may need a helper. Make sure you pull the shift arm out of the way and then have someone slowly rotate the prop as you push the lower unit back into the upper. The lower unit will have to be in gear so you may need to push the linkage rod down or pull it up. Side note, if you've not put in an impeller before and it's like the ones in my JohnnyRude 150s they are STIFF. I used a heat gun to heat mine up so the splines would bend to fit into the cup.
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Please elaborate on “pull the shift arm out of the way.”

Thanks for the tip tip on the impeller. This is my first...and it’s not going worth a damn so far 😄
 
The shift rod should connect to a horizontal pin or bar. On mine I have to remove two s-clip pins on the right side of the motor (when looking from the prop side of the motor.). The rod slides out from the shift pin, sometimes that pin slides back keeping the shift rod from moving all the way up into place. If you don’t have the repair manual for the motor I highly recommend investing in one. I downloaded a PDF version I keep on my iPad.
 
I recently did a water pump/impeller replacement on a 1989 Johnson 20hp (same motor), and other than was suggested before (you can also try pulling a little bit on the starter cord to rotate the engine as you push the L.U. back in) I can't offer anything further. (I did not encounter this problem on mine).
However, as far as the impeller is concerned, installing mine was the easiest thing I ever did on any motor.
Just apply some soapy water on the cup walls and edges of impeller blades, and push the water pump assembly down on the impeller (already in place on the drive shaft) while gently turning (CLOCKWISE!) the drive shaft, and it will just ease its way down around the impeller unfettered.
 
Thunderyacht said:
The shift rod should connect to a horizontal pin or bar. On mine I have to remove two s-clip pins on the right side of the motor (when looking from the prop side of the motor.). The rod slides out from the shift pin, sometimes that pin slides back keeping the shift rod from moving all the way up into place. If you don’t have the repair manual for the motor I highly recommend investing in one. I downloaded a PDF version I keep on my iPad.
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I definitely need to invest in a repair manual.



Jupiter Dinghy said:
I recently did a water pump/impeller replacement on a 1989 Johnson 20hp (same motor), and other than was suggested before (you can also try pulling a little bit on the starter cord to rotate the engine as you push the L.U. back in) I can't offer anything further. (I did not encounter this problem on mine).
However, as far as the impeller is concerned, installing mine was the easiest thing I ever did on any motor.
Just apply some soapy water on the cup walls and edges of impeller blades, and push the water pump assembly down on the impeller (already in place on the drive shaft) while gently turning (CLOCKWISE!) the drive shaft, and it will just ease its way down around the impeller unfettered.
Click to expand...


This problem I’ve encountered is self-inflicted….through and through. My God I was furious.

But I did wind up getting it off. Sorry I haven’t replied until now. Work has been running me ragged. I wound up unbolting the water pump housing bolts and that allowed me to drop the driveshaft all the way down, which then allowed me to move the water pump housing upward to let me access the shift linkage and take off the plastic lock and the threaded end.
I got the impeller out…it was completely toast. Replaced the impeller, keeping careful mind of making sure I was rotating clockwise. Put everything back together. I just now had a chance for testing and I was completely shocked that the engine still runs, shifts from neutral to forward to reverse and back. As much and as hard as I beat the lower unit with a hammer to try to get it to go up or down it’s a miracle nothing gave way and all is still functioning.

However…..unfortunately….despite the new impeller….there is no piss stream still. Unless I’m looking for it to come out in the completely wrong place, there is no water coming out, signifying that the water pump is functioning properly. This was supposed to be my easiest and quickest repair/upgrade that I’m doing to get it ready for this boating season and it has been utter disaster so far.
 
itsanss said:
However…..unfortunately….despite the new impeller….there is no piss stream still. Unless I’m looking for it to come out in the completely wrong place, there is no water coming out, signifying that the water pump is functioning properly. This was supposed to be my easiest and quickest repair/upgrade that I’m doing to get it ready for this boating season and it has been utter disaster so far.
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I know the feeling.... lot of us "weekend mechanics" do. lol
The one thing you should always do (maybe you did?) after replacing a water pump / impeller, and before reassembling the motor, is test the pump with the L.U. in a bucket (spinning the shaft with a drill) to make sure water is coming out at the grommet where the water tube hooks up.
So that's what you should do next. Good news is you will become an expert at pulling the L.U. off after doing it a few times! :)
 
Jupiter Dinghy said:
I know the feeling.... lot of us "weekend mechanics" do. lol
The one thing you should always do (maybe you did?) after replacing a water pump / impeller, and before reassembling the motor, is test the pump with the L.U. in a bucket (spinning the shaft with a drill) to make sure water is coming out at the grommet where the water tube hooks up.
So that's what you should do next. Good news is you will become an expert at pulling the L.U. off after doing it a few times! :)
Click to expand...


This is exactly why I didn’t want to be a mechanic as a career. Lol

That is is something that I did not do. I took the LU back off....I beat my old time of removal by about three hours....not kidding. Took it off in about ten minutes. Lol I’ve got it in a trash can full of water. Unfortunately, none of my three drills will fit the shaft! They’re 1/2” chuck drills. Even considered my drill press.Also considered my wood lathe. None will work. Wrapped the shaft with some duct tape and turned with a pipe wrench. No water. But I’m not convinced that that’s because it’s not working or because I simply can’t turn the pump fast enough with a pipe wrench. Is there any hope that a pipe wrench will work? If it absolutely has to be turned by a drill, then I may just buy water pump kit 0393630 because it would probably be cheaper than a drill ($35 kit). Lol

Thanks so much for helping me!
 
itsanss said:
This is exactly why I didn’t want to be a mechanic as a career. Lol

That is is something that I did not do. I took the LU back off....I beat my old time of removal by about three hours....not kidding. Took it off in about ten minutes. Lol I’ve got it in a trash can full of water. Unfortunately, none of my three drills will fit the shaft! They’re 1/2” chuck drills. Even considered my drill press.Also considered my wood lathe. None will work. Wrapped the shaft with some duct tape and turned with a pipe wrench. No water. But I’m not convinced that that’s because it’s not working or because I simply can’t turn the pump fast enough with a pipe wrench. Is there any hope that a pipe wrench will work? If it absolutely has to be turned by a drill, then I may just buy water pump kit 0393630 because it would probably be cheaper than a drill ($35 kit). Lol

Thanks so much for helping me!
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No problem, love to spread the knowledge (mostly acquired here from the "pros"), including this tip to address your drill chuck issue: The solution is <insert drum roll> a piece of water hose, a socket and two screw on clamps! :)
One end of the hose will be secured with a clamp over the top of the drive shaft (much softer on the splines than a drill chuck anyway), and the other piece will go over a socket of about the same size as the inner diameter of the hose piece, also secured with a clamp, attach the socket to the drill with an adapter of the right size for the socket (either 3/8 or 1/2 likely) et voila!

Good luck.
 
Well, that is just genius. Haha If everything goes according to plan, I will try that this evening after work. Awesome! Thanks VERY much for that tidbit. Now I'll be able to properly see if I need a new water pump or what.

I did disconnect the hose from the head to the tell-tale and blew compressed air through it. Copious amounts of air comes out the tell-tale...so at least that is not plugged or anything. After I check the water pump, I'll also check the copper pipe running up the engine to ensure that it's free of obstruction(s).

After I gave up on testing the water pump for the night, I tried to install my new (to me) tilt tube. Discovered that my engine won't accept a tilt tube....not even close. The outside hole in the bracket is big enough (which is all I really looked at), but then narrows down. So now it looks like I'll be buying a universal transom mount steering bracket. Another $140. Par for the course! Also have to hope that my steering cable I bought will still be the correct length now that I'm not using a tilt tube, but rather a transom mounted thing. Argh
 
You’re just getting into the fun! I have 2 150s that I maintain myself! One hex cap bolt is $17.49 and I needed 4! Just remember Break Out Another Thousand (BOAT):)
one other thing to try on the water not coming out the tell tale, use a piece of weed whacker line and run it up into the orifice and make sure there is no blockage like an insect, sand, etc.
 
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Thunderyacht said:
You’re just getting into the fun! I have 2 150s that I maintain myself! One hex cap bolt is $17.49 and I needed 4! Just remember Break Out Another Thousand (BOAT):)
one other thing to try on the water not coming out the tell tale, use a piece of weed whacker line and run it up into the orifice and make sure there is no blockage like an insect, sand, etc.
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Break Out Another Thousand - I believe that with every fiber of my being. Bought this boat for $100 and now have over $3k in it in two years. Lmao

Ok! So....I took water pump back part just to check everything out. It’s all installed correctly. Did your water pump trick. Had to use a piece of all thread inside the water hose to affix it to my drill. Got her spinning! Had to use a s-load of hose clamps to keep the all thread from spinning inside the hose.

It’s not pumping water. Saw a video where the water level has to be up pretty high to prime the pump...I’ve got the water level in the barrel nearly all the up TO the pump. This thing is not pumping water. Sad face

Saturday it was 28 degrees. Today it’s 95. I’m sweating my tail off working on this thing! &#55357;&#56881;
 
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Not sure what racer means by 6" above the pump, but I had mine (the 20hp and several 9.9 / 15hp) in a bucket with water level at the same level as the base of the pump, to the point where some water will fall into the unit but still leaving the pump uncovered, and I could see water gushing out the grommet when spinning the shaft. (FWIW)
 
itsanss said:
It’s not pumping water. Saw a video where the water level has to be up pretty high to prime the pump...I’ve got the water level in the barrel nearly all the up TO the pump. This thing is not pumping water.
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Water pumps can be some kind of enigmas I reckon.... I had some on my 9.9's that looked absolutely perfect but wouldn't pump even with a new impeller, put a brand new pump and here comes the water! Very weird.
And yeah..... boats are not the place of choice to put your retirement money in! lmao
 
If the impeller housing or plate is pitted or have grooves worn in them the pump will either not work or work poorly. If you have any doubts just spend the nickle and do it right. If you know it sucked sand just take it apart and check it. After a couple times you should be able to replace the impeller rather quickly. Its that first time that can be intimidating it gets alot easier the second time.
 
racerone said:
Water has to be 6" above the pump in your test tank.---Hard for some to fathom I guess.
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Yeah, some people are just stupid.


Jupiter Dinghy said:
Water pumps can be some kind of enigmas I reckon.... I had some on my 9.9's that looked absolutely perfect but wouldn't pump even with a new impeller, put a brand new pump and here comes the water! Very weird.
And yeah..... boats are not the place of choice to put your retirement money in! lmao
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Well, that seems to be the boat that I’m in (pun!!).



kimcrwbr1 said:
If the impeller housing or plate is pitted or have grooves worn in them the pump will either not work or work poorly. If you have any doubts just spend the nickle and do it right. If you know it sucked sand just take it apart and check it. After a couple times you should be able to replace the impeller rather quickly. Its that first time that can be intimidating it gets alot easier the second time.
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Apparently the pump was just worn out enough that a new impeller didn’t do anything for it. Because I ordered a new pump and finally had a chance to install it last night, and, ta-da! Water! Coursing through the entire engine! It’s working just fine now! And even have a spare impeller to boot. Lol


Thanks again for all the help on this! This 20 minute, $9 job turned into a two week, $45 job. But it’s working! Now, back to converting everything to remote control now that I got the quick and easy part done. LOL On the plus side, I can take the lower unit off now in ten minutes or less. :)
 
itsanss said:
I ordered a new pump and finally had a chance to install it last night, and, ta-da! Water! Coursing through the entire engine! It’s working just fine now!
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Sounds awfully close to the experience I was describing..... lol

itsanss said:
This 20 minute, $9 job turned into a two week, $45 job. But it’s working now!
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You still beat the potential shop bill, and have that priceless satisfaction feeling of having fixed it yourself! :)
Glad you're back in business.
 
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