1985 25 HP E25ECOC Lower Unit will not come off

[tladewig]

Im trying to replace my water pump and in doing so I have removed the 4 bolts required to remove the lower unit as well as the nut and lock washer on the "pilot?" stud but the lower unit will not come off.

Also removed the water inlet screens and disconnected the shift linkage.

I noticed corrosion around the stud and applied Sea Foam's Deep Creep and I'm on my 3rd week of soaking it and it still will not budge. I give it a pretty good nudge to try and free it up every day. Nothing going my way.....

I've tried brake fluid, Deep Creep, WD 40 and Diesel. My neighbor mentioned mixing Transmission fluid with acetone but, I haven't tried it..... yet.

Did I miss a bolt somewhere? Perhaps under the cowling?
Is the saltwater corrosion that unforgiving?

There must be a trick to getting this lower unit off.

Please Help!

[Solarman]

Check parts diagram, usually the best way to see if any bolts are hidden? You might find a bolt under the trim tab, I have seen one on some motors there? Usually there are 5 bolts? If the pilot stud is the 5th, and no other locations, put nut on stud flush with stud and using a board hammer on board at stud (not too hard) to see if you can get any separation? Butt, be careful, it is aluminum and not hard to break.

Good luck.

[tladewig]

Thanks for the advise. Still will not budge.

[Solarman]

Generally, if all bolts (are they bolts, or studs?) are out, or loose enough, and still no movement at all, then I'd agree, it sounds like corrosion, or another bolt was missed.

If you get a slight separation (1/8 to 1/4 inch), then it would sound more like the drive shaft is stuck (rust, or old grease, acting like glue?).

If lower unit has studs, not bolts, then you may have to use heat and solvent, plus carefully located hammering on a board to help jar it loose. But don't hammer on the flat fins, they can't take it.

Good luck.

[tladewig]

The heat with solvents and alot of persuasion finally worked.
Thank you for the knowledge.

-Evinrude man for life!

[Solarman]

Make sure you clean and grease those studs and threads well, also grease the splines on the drive shaft, it won't hurt to wire brush those threads and studs to clean the corrosion off. Then a good water proof axle grease something that doesn't dry out.

Also, if the corrosion was that bad, be careful with the water pump bolts, they may be frozen as well.

Glad you stuck with it, and won the fight. Good luck on the repairs.
Post back if any other problems.