Ultrex lower unit repair.

[Thorntonk]

I just replaced all lower unit guts because of water intrusion. Question is would spraying flex seal help or hurt on the seams? Don’t want to have water damage again. Wasn’t a bad job and only cost about 170 bucks. Thanks

[ThomasD]

Wouldn’t hurt but if assembled correctly with new seals and o-ring then not needed.

[Thorntonk]

New seals, armature, brush plate, and brushes. Just nervous about it happening again. Little bitty orings but the seals the armature shaft goes through is what I worry about most. Conflicting videos on YouTube on how it goes together is confusing.

[bobcoy]

Have you pressure checked the shaft connection with the motor? That is where I would be worried about. Sounds like you did a good job with the rest. Good luck

[Mahomee]

It should never happen if you pull your prop off and tighten the bolts up once in a while. You can put dialectric grease on the o rings to help seal lube them etc.

[Thorntonk]

How would a fellow pressure check the shaft? I’m assuming it’ll be fine, sounds like this is a common problem and better o-rings are sent to repair after the fact.

[jrh_67]

I would juat make sure there was a little bit of grease on the o-rings...

[fishnfireman]

I sprayed mine about 4 years ago after having slight water intrusion.
However, the only things I replaced were seals and O-rings.

[bobcoy]

How would a fellow pressure check the shaft? I’m assuming it’ll be fine, sounds like this is a common problem and better o-rings are sent to repair after the fact.

You just have to get air blown into the shaft and look for bubbles. If you are bumpin stumps or rocks that junction of the shaft and motor can get leaky. I think they still sell the assembly (shaft and motor housing as one piece)
Just looked through MK parts. Looks like the only option now is the motor shaft assy. Complete . $700 assy(depending on sonar options). Hopefully it is not the problem. Might as well try and see if it still leaks. The entire assy if needed will fix anything thats messed up in there anyway.

[rodney_h]

I seal every MinnKota trolling motor column at the motor housing with a thin application of Silk-a-flex, have never had a trolling motor come back for water intrusion.

[bobcoy]

Which product and what kind of prep, please. Bob
I see several different products by Sikaflex.

[bobcoy]

It should never happen if you pull your prop off and tighten the bolts up once in a while. You can put dialectric grease on the o rings to help seal lube them etc.

These are the torque spec’s for the different motors. Quest is most likely different. Just an FYI. Those long skinny bolts are easily stretched with too much torque applied( will tend to loosen)
• 3 ¼” motors = 25-35 inch pounds
• 3 5/8” motors = 35-45 inch pounds
• 4” & 4 ½” motors = 40-50 inch pounds
• 4 5/8” motors = 40-50 inch pounds