Dag nabbit.......stuck bolt holding up my water pump repair.

Evenrude 25hp 1996 22" shaft.


I got a lil over enthusiastic removing the lower unit and snapped off a 1/4-20 bolt.

No big deal as Im a toolmaker and have removed hundreds of broken bolts.

Im trying to remove the long shaft...uh...Spacer? dont know what its called but the stud in the front of the lower spacet thingy unit wont budge.

This bolt.






I got the other 4 out no problem, but the spacer just rotates around this bolt without the bolt turning, its corroded in place. Pretty sure I could unscrew the end thats in the spacer if I could rotate it 360 and get it off that way, but the shift rod is in the way.

Im using "Eds Red" as a penetrant but wonder if heat would hurt anything.

Yep, you will have to heat it as it is corroded in that housing. Heat it and smack that housing smartly without going nuts and then spray the penetrant to it while it is hot. May take a couple times of this but it should allow the penetrant to seep in and do it's work. Patience is a virtue on that particular fastener. As they aren't exceptionally easy to get to 'til they are separated. Good luck.

Thanks for the heads up Catfisher.

For the moment I decided to try to work on the busted off bolt in situ, but if I cant get it without mucking up the threads Ill go back to this bolt so I can get this on the milling machine to mill out the busted bolt.


I did try some heat but didnt want to overheat anything and wind up with a short shaft motor. #-o

Well if you have been in tool and die making you know what you are up against. It is the hard white corrosion you get when you have dissimilar metals against each other. It will be packed in there like concrete. The heating cooling process along with a good penetrant usually works.

On a side note I like to coat those bolts with anti seize when I put them back. Not sure that it helps but it sure makes me feel better. LOL

nccatfisher said:

On a side note I like to coat those bolts with anti seize when I put them back. Not sure that it helps but it sure makes me feel better. LOL

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The OMC OEM service manual has one coat lower unit bolts with gasket sealing compound. Have never had a frozen bolt since and my brothers and I will service a dozen or more OBs used in saltwaters each year.

nccatfisher said:

Well if you have been in tool and die making you know what you are up against. It is the hard white corrosion you get when you have dissimilar metals against each other. It will be packed in there like concrete. The heating cooling process along with a good penetrant usually works.

On a side note I like to coat those bolts with anti seize when I put them back. Not sure that it helps but it sure makes me feel better. LOL

Click to expand...

Yeah this is no fun, but Im off this week so I have time.

I tried my best to drill it on center with a hand drill but you know how that goes. I did get it drilled through without messing up the threads so now I go in with a die grinder and a burr on the thick side, then try to collapse it inward on its self.

Welp, might as well get at it.

Well, I slayed that dragon.


Had to take it out thread by thread but I got it out.




Thread by thread.








Got the last bit turned sideways up in the top of the hole, but I wanted it out to get the last 1/4" of untapped hole tapped to make up for the compromised threads.







I kept going at with the carbide burr till I got it all out.








Then I went in with a tap to clean everything up and get that last bit of thread. There were about 1/4" of thread the bolt enven touched plus the extra 1/4" I gave it so im good with this.

I do them pretty much the way you do. When it gets to the removing the last of the threads and shelling them in I take a nail set and make a chisel point on it. The rounded back fits the contour of the hole and will allow you to get in tight and you can shell them right out.

It is just a time consuming process and knowing that if you get in a hurry you will cause yourself a whole lot more work you won't be happy with.

Looks like you got 'er whipped now, good job!

Well, I must have done something right.


I cant make the YT tags work....link.

https://www.youtube.com/watch?v=wye4KDxFJ6I

Yep, she appears healthy and happy now.

Yeah but now that Im making water I discovered a head gasket leak.

Not too bad but a dribble that amounted to about a half pint inside the lower cowl that accumulated over about 15min of testing.


Bah, headbolts were rusty anyway. :wink:

RaisedByWolves said:

Yeah but now that Im making water I discovered a head gasket leak.

Not too bad but a dribble that amounted to about a half pint inside the lower cowl that accumulated over about 15min of testing.


Bah, headbolts were rusty anyway. :wink:

Click to expand...

That shouldn't be a bad fix on that motor. If you haven't replaced it do yourself a favor and get a thermostat while you are right there and replace it.

Before you go at that head gasket look real good and make sure your pump indicator hose or fitting hasn't deteriorated and that is where your water is coming from. Seen that a few times.