165 Sterndrive Broken Bolts - Help

Mud Puppy

Petty Officer 1st Class
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276
Hi guys! Hoping someone out there can help me with some issues I have with an old boat I am restoring over on the Boat Restoration Forum.

The boat is a 1971 Invader Marine 17 BWV Deluxe Runabout with a 165 MerCruiser I/L6 and a 165 Sterndrive.

When I got the boat it was in pretty bad shape and I know from what I have read the older drives are not as rugged as the Alphas, but I have this one and would like to get a year or so out of it. I'll be broke after doing the floors, stringers, and transom. As it is, I will have to wait on the bow seat cushions and vinyl.






The studs and upper bolts were good but the Anodes had loosened and allowed water to take its toll on the transom which allowed more water intrusion.


Long story, short; I had two (2) bolts succumb to a very bad case of electrolysis and the busted removing the gimbal mount and the transom plate. The two (2) Anode bolts are completely gone, but since they don't screw in are not problem.

These bolts only stick out of the gimbal ring roughly 0.500" on both and are the bolts directly above the Anodes.



I have tried heating with a small torch to help draw in Blaster and a mixture of Acetone and Tranny Fluid and walking away until cool, reheating and doing the same over again to no avail. I've tried using external stud extractors and all I'm doing is rounding down the bolt so I quit.

I have weld sacrificial nuts to broken bolts before and had some success on machinery and heavy equipment, however with the dissimilar metals between the bolt composition and the ring and years of corrosion I think I am fighting a loosing battle.

I am kinda concerned with pulling the threads in the AL if they do start to budge loose, so I am thinking that I may be grinding them off flush, center finding and drilling the bolt and try to leave the threads intact. If I do that, I may very well be able to run the remaining threads out suing a small cove chisel and I can then try and restore the threads using a chase.

My only concern is, if I pull or damage threads, what are my options short of grinding and filling with AL rod to restore those threads by drilling and tapping.

Can Helicoils be used with marginal success? I think sealed, I should be able to get several years out of such a repair if I need to do this. Does anyone have any similar experience?

Thanks in Advance!
 
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achris

More fish than mountain goat
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May 19, 2004
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27,468
Re: 165 Sterndrive Broken Bolts - Help

Helicoils work very well in this situation. As the hole is gasketed all around, you don't even need to seal them...

Chris....
 

Bondo

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Re: 165 Sterndrive Broken Bolts - Help

Ayuh,.... Heli-coils would work, Just Fine,....

That said, I'd go find an MC-1 transom assembly from a freshwater boat, 'n scrap the 1 ya got,...

All but the bottom 2(which are aluminum) are supposed to be Studs, 'n Nuts, not bolts,..
I'd replace 'em all,..

Somebody's been there, before ya,...
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: 165 Sterndrive Broken Bolts - Help

Ayuh,.... Heli-coils would work, Just Fine,....

That said, I'd go find an MC-1 transom assembly from a freshwater boat, 'n scrap the 1 ya got,...

All but the bottom 2(which are aluminum) are supposed to be Studs, 'n Nuts, not bolts,..
I'd replace 'em all,..

Somebody's been there, before ya,...

Not on the early housings. Only the top 2 are studs (and the bottom anodes) the rest are bolts, installed from the inside though the inner transom plate.

Chris....
 

Bondo

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Staff member
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Messages
71,079
Re: 165 Sterndrive Broken Bolts - Help

Not on the early housings. Only the top 2 are studs (and the bottom anodes) the rest are bolts, installed from the inside though the inner transom plate.

Chris....

Ok,... I've seen old, just not old enough I guess,...
 

Mud Puppy

Petty Officer 1st Class
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Messages
276
Re: 165 Sterndrive Broken Bolts - Help

Helicoils work very well in this situation. As the hole is gasketed all around, you don't even need to seal them...

Chris....

Thanks Chris! I was hoping the gasket might be enough on its own being a flat gasket over a beaded seal.

Ayuh,.... Heli-coils would work, Just Fine,....

That said, I'd go find an MC-1 transom assembly from a freshwater boat, 'n scrap the 1 ya got,...

Thanks Bondo, I would but the Admiral has got me on a tight budget and still wants results (Splash the Summer) and the floor turned into floor and stringers, turned into floor, stringers, and transom so I'm trying to use what I've got.


Not on the early housings. Only the top 2 are studs (and the bottom anodes) the rest are bolts, installed from the inside though the inner transom plate.

Chris....

Yeah Chris, I found an old Sterndrive Manual with a parts breakdown and it shows just that, two studs and the rest bolts through the plate.


Ok,... I've seen old, just not old enough I guess,...

I was having a hard time trying to ID the drive early on being New to something this Old and on another forum I got a response back about how old it was; it was "Man is that Flippin' old! ~manufactured before my Dad was born" was the only identification I got back on it.

Okay, I do have underwear as old as the sterndrive and boat myself, but I won't go into that here. :clap2::clap2: Age is relative and my sterndrive is only as old as it feels.

Thanks All! Appreciate all the replies.



I do have a question on how to break down the gimbal from the bell housing too.

With mine being an older drive, and not having the Trim Limit and the Trim Sender in the gimbal pivot point, I also have different pins where the gimbal pivots up and down. I do have similar pins where the gimbal pivots from Port to Starboard.





^^^^There apears to be a small (say 0.125") pin directly above the grease Zerk in this photo which lines up with the center of the pin in the bell housing. Does this have to be drilled out before the pin can be turned? And if so, is there a tool for fitting the pin?






How is the gimbal removed to replace the bellows?
 
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achris

More fish than mountain goat
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May 19, 2004
Messages
27,468
Re: 165 Sterndrive Broken Bolts - Help

To remove the hinge pins, remove the 'nails' ('Pin aligned with pivot pin' in your picture), then run a screw into the hinge pin and pull it out with a slide hammer.

Based on a few things I saw in the pictures, the transom assembly is between 1969 and 1973...
 

Mud Puppy

Petty Officer 1st Class
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Messages
276
Re: 165 Sterndrive Broken Bolts - Help

To remove the hinge pins, remove the 'nails' ('Pin aligned with pivot pin' in your picture), then run a screw into the hinge pin and pull it out with a slide hammer.

Based on a few things I saw in the pictures, the transom assembly is between 1969 and 1973...

Thanks Chris! And your dead on with the dates. Sterndrive matches the Engine ID, both original to the boat.

If y'all get a change, please stop by and checkout my Demo (Restoration). I started it in September and have patiently waited till the spring THAW (which hasn't happened yet) to start puttin' her back together.

Stop in and say Hey! :horn:
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: 165 Sterndrive Broken Bolts - Help

....and have patiently waited till the spring THAW (which hasn't happened yet) to start puttin' her back together....

What is 'thaw'???? Is that like when your hit your thumb with a hammer and it's 'thaw'??? :D :D :D

Chris......
(Lives where the ice never comes :))
 

dozerII

Admiral
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Oct 25, 2009
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Re: 165 Sterndrive Broken Bolts - Help

Those "nails" that hold the hinge pins in are bent over into a recess on the front side of the ring, you can get a little screw driver in there to start to straighten them then a pair of pliers. They are NLA so if your careful you may be able to reuse them.
 

Mud Puppy

Petty Officer 1st Class
Joined
Sep 8, 2013
Messages
276
Re: 165 Sterndrive Broken Bolts - Help

What is 'thaw'???? Is that like when your hit your thumb with a hammer and it's 'thaw'??? :D :D :D

Chris......
(Lives where the ice never comes :))

Lucky!!! I however, since the movie Crocodile Dundee, have been deathly ascared of kangaroos. Problem is I always what to travel to your part of the world; I just don't want them shooting at me.

Those "nails" that hold the hinge pins in are bent over into a recess on the front side of the ring, you can get a little screw driver in there to start to straighten them then a pair of pliers. They are NLA so if your careful you may be able to reuse them.

Thanks DozerII! Roger WilCo! Headed in to the shop so I'll look it over.
 
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