DT225 Lower Units Stuck

[SirIzzy]

I acquired a pair of DT225's. These motors are from 2001 and are a counter rotation pair. They were abandoned with the boat and have not not been run in 8-10 years. Surprisingly the motors appear to run great. However there was no telltale pissing water which did not surprise me. I suspect the impellers are dried out and probably broke apart when I started the motors. So the next step was to drop the lower units. But I cannot for the life of me get either lower unit to drop. First of all on both motors 6 of the 7 bolt heads broke right off. I was able to successfully remove one bolt from the fin area on both motors as well as each bolt under the zincs. But no matter what I try the lower units will not drop. I'm working on plans D and E (maybe F and G) and wanted to run the following questions by anyone that knows or is willing to give any advice. Thank you in advance ...
1. Are there any other lower units that will fit? If I wind up cutting the legs or totally destroying them, do I need to find only DT225 lower units, or will another manufacturers lower unit work?
2. I'm thinking one solution is to not even try removing the lower units, but rather rig up an external run dry type pump wired to the ignition that feeds the thermostat inlets. If this works, run the motors this way and maybe get another year or more service out of them? Am I crazy thinking of this plan?
3. I have tried making a press that pushes a smaller bolt up into the sheared off bolts, all this accomplished was cracking a fin. Any other suggestions/ideas would be greatly appreciated.

Thanks,
-Izzy

[Murray]

https://www.boats.net/catalog/suzuki...1001/gear-case

The above link shows 6 bolts plus one more under the trim tab, 7 in total, so it sounds like you have all the bolts out. Most likely the drive shaft splined end is frozen into the engine.

https://www.boats.net/product/suzuki...30adf4e7a3ccc4

The above link is your lower unit, if you scroll down to the bottom on the right hand side you will see a list of other years and engine that share that part. The links came from “Buy Suzuki Outboard Parts” at the top pf the page.

Good luck with the frozen steel bolts in an aluminum housing.(dissimilar metals) Application of heat can’t hurt. Perhaps you might want to consider a machine shop? To dislodge the drive shaft from the engine housing will also be a challenge, if you search this form I remember reading a post that someone else had the same issue. Perhaps small wedges tapped in gently with a hammer, just remember that the cast aluminum will easily break.

[SirIzzy]

Thank Murray, I do have all the bolts out, well at least the bolt heads are clear as most snapped off so I ground them down. I believe what is sticking is the alignment pins, the casing itself, and/or the shaft ... It could be one or all these corroded and sticking. The foot will not budge! No gap. I am not getting ANY separation at all no matter what I do. I did try heat, I've been spraying with PB Blaster for many days now, tapping, and even tried to fabricate a press to push on the broken bolts ... Nothing!

Any thoughts on my idea to leave it alone and use an external water pump?

[Solarman]

Before starting make sure tell-tale holes are not blocked up. But yes, you will still need to get bolts out and replace impellers. An external pump is a waist of time, as pieces of old impeller will block water jacket passages farther up.

I would also recommend a machine shop, as they can probably drill the existing studs out without damaging lower units. The drivers will most likely be somewhat frozen from dried grease, but constant pressure, separating the lower units on both sides equally, along with using a hammer on a wooden block at the front of prop shaft cone, to jar is what has worked well for me (soft wood is best to avoid damaging housing). Usually you can get at least a 1/4" gap between the two sections, enough for a couple wide putty bladed screw drivers in opening, as close to where drive shaft is. Put foam or layers of thick cardboard under skeg, it only needs to drop about 2" to clear the splines. As it works down try to spread the load out with wider blades, or add wider putty knives where screw drivers are. Can't use heat here just constant pressure, plus jarring it a little at a time.

Oh, and don't forget the shift rod connection midt b.e un-pinned.

Good luck, post back on what you end up with.

[SirIzzy]

I will keep trying as I'm not one to give up easily, but I am not getting any separation at all, so I can't even try any kind of wedges. Will post back if I make any progress or have further questions.

[SirIzzy]

Not wanting to argue but can anyone explain why an external pump would be a waste of time? I have found a 3 gal/min 12 volt continuous duty pump that I'm thinking of rigging up and trying. Does anyone know what the flow rate for the impeller is?

What I want to try is hooking up the intake of the external pump to the lower two ports on the cylinder heads and the output to the top two ports where the thermostats are located. I was thinking that the pump will draw the water up from the leg and circulate it just as if was pushed up by the impeller. Since I have no idea what the flow rate is, I don't know if a 3 gpm pump will be enough, but it would only take me a few hours to rig this up and try it. Those are just a few hours the penetrant continues to try and loosen the housing anyway.

Having said that I respect the opinion of folks experienced so I'd love to hear why this would be a waste.

Thanks again,
-Izzy

[Murray]

So buy doing that you are reversing the water flow direction, water will be entering via the thermostat rather then exiting the thermostat? That would only work if the thermostat was removed? No thermostat then what controls the engine temperature? What would stop the water from taking the path of least resistance and exiting out thru exhaust? I’m really not familiar with the exact path the water takes, all the nuances of how all the components are cooled, my thoughts would be it’s an intriguing idea but if it doesn’t work are you prepared to potentially destroy the engines?

[SirIzzy]

I realize it would be very helpful to know the path the water takes as well as the volume, though I could probably come up with a way to calculate volume ... but that would be a whole nother discussion.

In trying to figure out the flow, all I have to go on is parts schematics. We can all agree that water gets pushed up the water tube from the impeller. I believe the water pushed up by the impeller goes into a cavity at the bottom of the block. It then must fill the cavities which would include the lower hose area. I could not tell or decipher if the water then goes up into the thermostats from the lower hose or if it gets pushed though the block and exits from the thermostats and down the tubes to the lower ports, and down to the exhaust. Either way, I'm thinking if the thermostats are closed, the water would get pushed back through the block, until the thermostats begin to open.

It goes without saying that I don't want to destroy the engines but if I cannot get the lower units to drop what else can I do? I'm gonna guess that if I take the motors to a marine repair shop (dealer) its gonna cost me at least a few thousand dollars to have them do the work and that is just labor. If the lower units need to be destroyed and replaced its gonna be at least another couple to four thousand just to buy good lower units. If my guestimates are right, a repair from a dealer will easily exceed $6K and could quickly approach or exceed $10K. I have seen what look like good (approx same years and HP) Mercs and Evinrudes for $7K to $10K complete with controls. It makes me sick to my stomach knowing that replacing a few hundred dollars in parts is all that is needed but those darned lower units are stuck!

[seaveepete]

Happened to me... see my post on THT about the fix....
https://www.thehulltruth.com/boating...self-save.html

Good luck.

[Solarman]

Exactly why i suggested a machine shop to remove the bolts on the lower unit. They have the proper tools to drill and repair most all of those issues. After those bolts are removed, whose to say the lower units won't work down and come off?

The external pump, if 3 gallons/ min flow rate is (?) enough the cooler water needs to enter from the bottom through the exhaust chambers, and other areas of the block, to the thermostats, then through the heads on the way back through the leg cooling the exhaust passage on the way to exit. Inboards, & I-O motors use external pumps that pull water from the hull, or foot of the motor, but the first, coolest water flow, goes into the exhaust headers then through the thermostat (opening by temp to regulate flow needed) then to the block, and then back mixing with the exhaust on the way out. At higher rpms, I do NOT believe 3 gals/ min would be enough?

Good luck, but I still recommended a machine shop to get all the bolts out first. A good machine shop may even have the ability to heli-arc weld, and repair any damages to the housings.

[Murray]

I’m fairly confident that water is pushed up through the block and exits out through the thermostat, when opened, to the water return hose in my engine (2009 DF90A) I would assume all Suzuki’s would be the same.

[briscoe]

The forward reverse linkage would be what I think is holding it. Water can get in the top and corrode. I would hope you have some wedges to separate the units. I had problem with separating mine and the wedges did the trick. It was corroded at the spline at the top and would not drop all the way down from mid unit.
Another thing, remove the power head. Just unbolt and lift it up with a motor jack. Not that much work. Lifting off power head would mean that if it is still stuck it's the forward/reverse shaft.
LAST THING take a look at the linkage shaft (?). At the bottom where it attaches to the water pump you might be able to get a wrench over it to gI've an area to strike down with a wrench

[briscoe]

See where the wrench is sitting? It will allow you to separate the shaft from the top where it is stuck. Then you can separate it from the water pump at the bottom. Capish?

[SirIzzy]

See where the wrench is sitting? It will allow you to separate the shaft from the top where it is stuck. Then you can separate it from the water pump at the bottom. Capish?

Hmmm ... I do have the shift linkage disconnected. Are you suggesting to pry down on the shift bar that goes down into the foot? Is there not a concern of bending it?

Just so you know, I had a strap attached to the foot which was attached to a come along which was attached to my truck. I had a LOT of tension on that strap and it would not budge! Before attaching to my truck I attached to a Subaru Baja ... the come along tension pulled the Baja backwards ... point is I was putting a lot of tension on the pull and no movement AT ALL!

If you are suggesting prying down on the shift linkage, then maybe that in combination with tension on the lower unit via the come along???

[SirIzzy]

I’m fairly confident that water is pushed up through the block and exits out through the thermostat, when opened, to the water return hose in my engine (2009 DF90A) I would assume all Suzuki’s would be the same.

Please realize I am not planning to go this route unless plan Z fails, but just thinking out of the box if plans I get to plan Z and it fails ... then forget my previous external pump suggestion, I think a better one would be to just plumb an external pump into the service port ... it directs water through the proper channels.