Lower Unit Removal on Johnson 225

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boatrookie

Member
I am in the process of changing the water pump on my Johnson 225, which is on my 84' model V20. The best I can tell, the motor is the same year, but was told by previous owner it was an 86 model. Either way, I have all of the bolts out, double checked, but cannot get lower unit off. There is a slight gap all the way around where it meets up, but that is the most I can get. I have read that it could be where it splines together at engine or something??? I am definately not familiar with these but would be considered very mechanically inclined. Any help on what I can do here to get it off without causing significant damage would be so very appreciated. Thanks in advance for the tips/suggestions!!
 
Did you disconnect the linkage for the shift mechanism just under the carbs? Johnson has a disconnect under the carbs that when partially disassembled will release the shift rod that travels from there to the lower unit. It will hang from the rod if you haven't made the disconnect.
 
And have you removed the bolt beneath the steering torque plate (trim tab)?

We have had instances where the shaft was seized to the crank or the o-ring on the shaft just held it unbelievability.
We'd first engage the foot in gear and try to push down with our foot on the edge of the prop to see if it'll drop. This simply adds a little pressure to the splines and some downward force.
If that didn't produce some movement, we'd then start a wedge and drive system to start separating the foot from the midsection. This starts out as small wood wedges in various locations to protect the foot and midsection and driving a screwdriver between them. Then progressing to larger wedges and chisels as it separates.
Have had an instance where we made no appreciable progress and let it set for a few days with the tension of the wedges. Checking it a few time a day and driving the wedges tighter. Finally easily breaking free.
 
I forgot to mention that I did remove the bolt from the shifter linkage as suggested along with the bolt underneath the trim tab, I apologize. So, I guess I should just start with some small wood shims and slowly increase the size as it drops? I will try that because a screwdriver did seem to mess things up a bit, which brings me to another question. Once I get the lower unit off, can I just repair what I "damaged with the wrong tools" before assembling with no future problems? I mean, besides cosmetics, is it critical that there is a water tight seal where the lower unit joins back up because if there is, I am sure I can repair it with no problems. I guess you guys see where the name "boatrookie" comes from, huh?!! I do appreciate all of the help though........
 
I had a older 225 at one point, and when the water pump went the same thing happened to me! After trying everything and hanging the motor upside down for a few days still nothing?? BS the founding member here came over and tried all his tricks and still nothing, sold the motor to another guy and that was the last I ever saw it, Thank God!! But till that it was a great motor.
 
Also, does anyone know what the philips head screw right beside the water inlet is and if it has to be removed? I am not referring to the fill and drain plugs, but this one is right beside one of the inlet holes and it's only on one side. Thanks
 
The Phillips holds the strainer in. No need to remove it.
There's always water leaking between the foot and midsection, it's not sealed. Just file off any burrs you created.
Also forgot to mention (if need be) with the tension of the wedges in place, you can whack the crank with a brass hammer. Careful to not damage the nut and flywheel. This jarring and already downward force might free it.
 
Pinion bearing retaining screw, but it is not a phillips. Manual says the V-6 doesn't use the pinion bearing retaining screw. So What Tsubaki said..
 
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this is why you change a water pump every year. had one on an older mako do the same thing,
like tsubaki said, keep tapping the wedges a little every day, went out one morning and it was laying in the driveway.
 
That is what I will do and pray that I too will walk out one morning and it be laying on the ground! Thank you all for the information
 
Okay, I might be talking out the wrong orifice here but this is more ancient history than modern science.

The key is to use wooden wedges and wait.

Why?

Wood will expand and contract relentlessly with changes in humidity. The Romans, Greeks, and even us Polacks (I think) used this method to quarry rock. Goggle it if you don't believe me.

One thing, a wide metal thingy, like a putty knife blade between the wood and the lower unit case will spread the load and keep the wood from just compressing.

Wood, moisture, wet, dry, rinse repeat.
 
Thanks for the info. I have got some wedges in it now and slowly working with it. The problem is I only have about an 1/8" in. gap right now, so getting something in there is proving to be fairly difficult. I will keep at it though.
 
Ok, so I tried running it with all the bolts out today. I put it in gear back & forth and nothing. I am going to try something else I had an idea about. My question is should the shifter be in forward, neutral or reverse before I disconnect it or does it matter? What I am going to do is put threads in the the bottom of the lower unit where the 4 bolts go in from the bottom (currently not threaded) . I am going to put a piece of metal in between the lower unit and middle section then SLOWLY tighten my new bolts upward pushing against the metal pieces and see if it will push the lower unit down. Any thoughts about this or should I not go this route?
 
Sounds like a stroke of genius about using the bolts taht way. I did something sililar to pop the powerhead off of my old Yamaha.

It's certainly less drastic than cutting a window in the midsection and torching the driveshaft in half, which I have only heard about...
 
I sacrificed a midsection once to free up Reelapeelin's powerhead. Did save the lower, but that turned out to be toast too, what a PITA. I feel for you, sounds like you have a plan. Saw a guy turn his mota upside down hung by the lower with the powerhead just above the pallet below. I thought he was kinda nuts but it worked out. His theory was the Blaster he was spraying on the driveshaft was running down into the splines and working on the corosion and the powerhead was heavy enough to do the rest.
I always liked hanging the rear of the boat with the flywheel but it requires removal of the powerhead bolts, cherry picker setup and the replacement of the powerhead gasket. Tons more work but gives you lots of pulling power/leverage.
 
but as far as the shifter linkage, should I have it in forward, neutral or reverse prior to removing it again or does it matter it's position?
 
To me, I don't really care what position it is in on the Johnrudes, the way the linkage hooks up it can only go back together one way right. Mercs are different with the splined shift shaft attachment at the foot it matters, BUT not on your motor. You can always remove the shift cable from the saddle to make the linkage line up after the repair/maintenance.
 
Cool, thanks for the information. I am going to give my idea a shot tonight, and see what happens. I have been thinking about it and I keep leaning torwards just applying a little pressure everyday on the bolts rather than just wrenching them down all in one day. I am hoping my strategy works as I am quickly running out of ideas.
 
Be very carefull not to muck up those threads. Not very hard to do.

I had one disobey me one time. I ended up taking it to the shop and they got it off but did not tell me how.
 
One last question before I proceed with my plan on trying to remove the lower unit. I was thinking about drilling a 11/16" hole in the center part of the engine up torwards the top where it meets up with the actual powerhead section so that I could see the driveshaft and hopefully be able to get some penetrant on the splines. I will lower the nose of the trailer to the ground and tilt the motor all the way up to help. My question is what is normally behind that section or is it just hollow? I can come back later and put threads in that and just put a bolt in it when I am through to plug the hole I made, I just want to try and get something on those splines before I start with the bolts. Your thoughts as they are always appreciated and helpful.
 
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