Lower Unit Bolts Snapped

[Omega Whaler]

In the process of restoring my 76’ Evinrude 50 HP that I recently purchased with my Whaler then bad luck hit. When I was working on removing the lower unit the four bolts that are on the sides of the lower unit, snapped. Yes, all four heads snapped right off and left a white powered. The bolt by trim tab did not give me any issues. So, now I can’t get the lower unit to drop down. I did remove the shift linkage. I’m thinking that just a little bit of thread is left holding the two together. Because of the fins, I don’t believe that I can get a drill to remove the old bolt.

Any ideas would be greatly appreciated.

Thanks

 

[boobie]

Try some heat around the broken bolts along with a rubber mallet. This may work providing the drive shaft isn't frozen in the crankshaft.

 

[F_R]

Are you sure it is a '76? Anyhow, forgive me if I am wrong, but I think there is another bolt above the trim tab. Did you remove the trim tab to look?

 

[Faztbullet]

Trans fluid and acetone mix and soak generously...

 

[Omega Whaler]

Thanks for the suggestions everyone. I’ll give it a try and see what happens.

 

[oldboat1]

'74 or '75 50, maybe: https://www.iboats.com/shop/engine-parts/1975-Evinrude-50542B-Gear-Case-Parts.html 2 bolts from underneath.

 

[Omega Whaler]

By the its plate the motor is a 55673E, which should peg it as a '76 which is what I understand.
Other than the 4 bolts on the sides of the exhaust. I did remove the bolt on the trim tab and the one directly in front of it the gear case to HSG. That is when I thought something this isn't going to be good.

 

[F_R]

Yep, it's a '76, but it is a 55hp, not 50 as stated in the OP. I am used to seeing a bolt that is accessed by removing the trim tab, but it doesn't show on the parts list for your motor, so perhaps it is not used on yours (????)

 

[F_R]

Just to show that I am not totally crazy, this is for a 75hp. #68 is the bolt in question. Still conceding it may not be used on your 55hp.

 

[Omega Whaler]

Following up... I've although I think the Acetone/ATF mix and heat would have been best had I don't this prior to the bolts snapping. Thanks again for the ideas, much appreciated. Regardless I've given it a shot hoping that either of those ideas might work - sad to say the lower unit is still affixed to the housing.

Trying to get a drill in the holes to clean out the old bolts isn't working either because of the fin of the lower unit is obstructing the hole. I've also used a Dremel with a grinding bit to try to clear out the bolts.

Still searching for a remedy. Here is a couple pictures to see what I'm working with. I just hope that I can keep this old Evinrude ticking.

 

[racerone]

Put some weight on the lower unit.-----Start the motor up on muffs / flusher unit.-------Open a cold one.-----Perhaps the shaking / vibration will help.------It is that white powder ( aluminum oxide ) that is holding it.

 

[racerone]

I have pulled the lower unit off using a hydraulic puller too.------Your results may vary.

 

[DouglasW]

I would apply some heat to either the front or rear of the lower unit near the bolts (but not on them). Try pulling down on the heated end after it's heated. If you can get one end separated slightly, switch to the other end. You can use an ordinary propane torch from Walmart.

I have used that technique often, usually combined with some "cold/freeze" spray on the bolts.
https://www.amazon.com/MG-Chemicals-403A-Super-Spray/dp/B008UH3NB8

 

[Omega Whaler]

Success!
I used a straps to put pressure on the lower unit. Along with using wood and hammer to break it loose. This old Evinrude has seen some life. As you can see lots of rust on the shaft.Thanks guys for all the help and support!

 

[oldboat1]

Well done! I would first try cleaning it up with mineral spirits and shop rags, while soaking bolts with acetone and ATF. When trying to remove them, try rocking gently clockwise and c.clockwise with vise grips.