98 dt 200 LU UNIT issues

[mako238]

Saw fluid coming from weep hole when I had the motor tilted. Pull bottom drain and nothing I mean nothing but clear water came out with a few drops of oil at the end. Boat ran fine a month ago. No leaking around prop/driveshaft



Pulled lower unit and checked gear gase



I wonder if I just need new gear case seals. Hard to do? Any special tools required?

[Solarman]

So basically way you're saying, there is no gear oil in lower unit, just water?
Yes, you either have bad seals, or a broken case? However, if you only removed the lower drain plug, did you get about 1.5 liters of water out (approximate amount gear case holds)?
If nothing but water, I would get all water out, refill with gear oil, and get all seals ordered, and replaced. You do not need water sitting in gear case, rust can damage small parts quickly.

Good luck

[mako238]

Pressure tested and drive shaft seal is leaking. I've never messed with replacing any seals on LU. Only water pump
What tool do I need to spin the large nut off with?

[mako238]

This is what I am referring to

[Solarman]

Do you have to pull the housing to change seal? You didn't show enough of seal to tell?

Post back and let us know.

[mako238]

Seal came right out with no problem. Took 11 minutes
I'm gonna replace gear seal and water pump while the LU is off

[mako238]

[mako238]

Ran Great for almost a week and then all of a sudden one day lower unit got trashed. My thought is from the seals being bad water getting in damage was already done all I did was prolong the breakdown. So now I'm in the process I rebuilding the lower unit myself. Got the seals out how to make my own tool to remove the spanner nut. I can't get the bearing carrier out I tried using a slide hammer and the bearing carrier won't budge.

[mako238]

Here is where I am at

[Solarman]

Nice work on wrench. I could use your welding talent.
My dt140's don't have such a nut. I have 2 bolts, holding an aluminum bearing housing in my LU. It only requires a 2 bolt puller, bearing housing is sealed with orings.
I'm surprised it required heating to remove, but then again, that was smart. Knowing corrosion and how that could affect threads as well as the housing. Heat does work with corrosion, good call.

Check your parts break down on shift rod, and drive shaft bearing assy's, both may need to be worked carefully (might take a few pics before?), or removed before prop shaft slides out? And there may still be o ring seals on the bearing housing still inside (last pic of LU, after nut removed) that may stick?

Try to keep everything on shaft as you slide entire gear drive assy out.

Good luck, keep us posted. Thnx for the great pics too.

[mako238]

Nice work on wrench. I could use your welding talent.
My dt140's don't have such a nut. I have 2 bolts, holding an aluminum bearing housing in my LU. It only requires a 2 bolt puller, bearing housing is sealed with orings.
I'm surprised it required heating to remove, but then again, that was smart. Knowing corrosion and how that could affect threads as well as the housing. Heat does work with corrosion, good call.

Check your parts break down on shift rod, and drive shaft bearing assy's, both may need to be worked carefully (might take a few pics before?), or removed before prop shaft slides out? And there may still be o ring seals on the bearing housing still inside (last pic of LU, after nut removed) that may stick?

Try to keep everything on shaft as you slide entire gear drive assy out.

Good luck, keep us posted. Thnx for the great pics too.

Shift rod was removed already. From parts diagram looks like drive shaft has a threaded geared collar. Haven't had time to dig any farther.
I did purchase another used LU to slap on while i try and rebuild this one. Motor wrongs strong with 115psi on all 6 so that's why I feel it's worth hanging onto for a little longer