Suzuki DT25 lower unit diassembly...

[shawnc]

I'm in the process of trying to replace the water pump impeller in my '78 DT25. I've removed the prop shaft, disconnected the shift rod, and snap ring/pinion from driveshaft. The bottom of the lower unit (black section) will drop about 1/2 ", but it seems that the driveshaft is preventing anymore movement. It is not moving when I drop the black section.

I removed the four bolts (of course one broke off) that hold the next section (silver), but it doesn't want to budge. I can't see any other access panels that would allow me to disconnect any driveshaft coupler or pin. Is this just stuck tight from the gasket or RTV sealer, or am I missing something? I was whacking pretty hard with a mallet and block of wood, but it's not budging, and I didn't want to start driving a pry bar between the sections if I am missing another fastener, and I don't want to crack the housing.

When I drop the black section, I can see the lower part of the water pump assembly, so I'm sure I have to drop the silver section to get to the top of the water pump and to get the impeller off. I have a manual but it doesn't have any specifics or even mention this two part lower unit, and the pictures look like the entire unit is off with the driveshaft and waterpump tube still attached.

Any suggestions would be very helpful. Thanks!

 

[shawnc]

Re: Suzuki DT25 lower unit diassembly...

Update on my progress. I managed to get a box end wrench inbetween the lower unit halves, loosen and remove the three nuts holding the water pump to the lower unit and I got the black section off.

However, I still cannont get the driveshaft to budge. It seems like it has a snap ring or something higher up in the driveshaft casing that won't let come out.

My problem now is that there are bushings on the driveshaft that ride in the lower unit bearings. I drove the retaining pins out, got the bottom on off, got the top one to slide, but the middle one must be pressed on. I tapped it with a screwdriver/hammer and it did move a little. My only option is to try some heat on it and try to get it off so I can slide the pump assembly off. I see no other way to get the water pump/impeller off without the driveshaft coming out.

Any ideas on the driveshaft? Are the splines so rusted that they won't move or is there normally a snap ring/retaining ring higher up to stabalize the shaft vertically? I can't feel any vertical movement of the driveshaft at all.

 

[shawnc]

Re: Suzuki DT25 lower unit diassembly...

I am about to give up on this old clunker. I disassembled the lower unit, albeit, in an bassackwards way, but removing the bushing on the shaft that rides in the lower unit bearings (with some heat and a lot of pounding). Got the water pump assembly off (basically from the bottom up...backwards).

I found that the reason I could get the lower unit off was that the key for the impellar was preventing the pump from sliding off...even bigger problem was that I did this comepletely wrong b/c the driveshaft itself will not come out. I'm assuming it is rusted fast in the crank.

I'm not about to spend more time on this motor and I'm about to consider it a total loss (given what I paid for the boat, trailer and motor, not much of a loss).

Has anyone else had problems with their driveshaft getting stuck like this?