Broken bolts and headaches

[Kinetic]

Hello All,
New here and hoping to get some suggestions and offer anything in return at a later time. I have a 1988 Catalina 34’ with an M25XP. Went to install a new thermostat cover and instant trouble. Both bolts broke on removal. And in all seriousness it was with little applied pressure. I was rather surprised.
Tried everything to remove the broken bolt studs with no success as I believe they are rust welded in there.

From what I can tell I have 2 options.
1)Drill them out and tap a larger bolt thread. I am not confident with doing it this way as the thermostat cover would then need to be drilled larger and the amount of material space on the edge is already rather thin. Any larger bolt hole is questionable. Along with that trying to tap new holes is not easy with out on the water (on a mooring) as well as the space to try to do a proper tap is problematic.

2) replace the water flange. I have locacted the needed part and dont have an issue with the price and am always a fan of new parts anyway. Problem here is I can not see a way to remove that flange without basically a complete tear down of the front of the engine which I am not going to get myself involved in and really dont want even the most experienced mechanic opening the possible can of worms that could come with that much. There are a few bolts that appear cant be removed without the front cover of the engine removed.

ugh! Any ideas or any body ever deal with this?

thanks in advance.

 

[dLj]

Photos' are always welcomed.

Besides the two options you mentioned above there is at least a 3rd option that I have done in the past. It's not easy and it's not fast.

Drill a center hole down the broken bolt and using a Dremel to remove as much of the old bolt as possible, being sure to not hit the female threaded portion. There will come a point when you can then remove the majority of the remaining threaded bolt. You can then run a tap through the hole and clean up the threads of the female side.

To give you an idea of the time involved, I recently did this on a broken threaded piece that was actually a 000 size thread - it took me a week working under a stereo microscope and VERY carefully and VERY slowly removing all material needed to perform the end result. Now, yours will be easier as it's much larger, but it will still not be easy to do.

Option 4 is to use an easy-out, but from your description, I'm not sure that is going to work.

dj

 

[Kinetic]

Thanks for the quick reply Dj. Dremel and then running the tap to clean out if the threads is a good idea not considered. Hopefully I did not already hurt the current threads!
thanks again.

 

[dLj]

Just a note on getting the first hole into the broken bolt - typically the top of the broken bolt is not flat, so you need to make a small flat, then I'll use a center punch to give a good spot for the first drill to not wander. I have often had to make a specially sized center punch. I have drift pins that I used to make a center punch from - I like having the straight sides. Depends upon where the fractured bolt surface is, in or out of the hole.. Out of the hole is easier, you can take a needle file and file a flat...

dj

 

[Hello Below]

Call me a wimp but this is about the time I call in the experts a.k.a. mechanic. These guys have the equipment and know how and experience. One hour or $100-$150 maybe the best money you have ever spent.

 

[kloudie1]

There is the Helicoil option if you want to go back to original bolt size and thread.
centerpunch first then drill with a left handed drill bit. Pilot hole first, then larger. If lucky, the drill may back out the bolt. If not finish with the Helicoil bit which is in the kit with the tap and coils.

 

[dLj]

There is the Helicoil option if you want to go back to original bolt size and thread.
centerpunch first then drill with a left handed drill bit. Pilot hole first, then larger. If lucky, the drill may back out the bolt. If not finish with the Helicoil bit which is in the kit with the tap and coils.

Works only if you have enough material around the bolt holes to put in an oversized hole for the helicoil.

dj

 

[dmax]

I would go the EZ Out route if you can drill straight into the bolt. Apply some PB Blaster (or similar) early and often before attempting. I would also heat it up with a torch before backing out just to be sure (get it as hot as you dare without destroying anything). Should come right out. Otherwise, it's the more drastice measure mentioned above.

 

[smokey73]

A slight alternative on @dLj method. I have use this to remove the remains of a broken bolt on a 1964 Vette and it worked well, took some time, but probably less than the dremel method. All the prep stuff to start is the same including the center punch, pb plaster etc. Once you get a good centered small hole, instead of using the dremel, use progressively larger drills (small increments) to enlarge the hole. When you get to very little metal of the original bolt left, use an easy out to try an remove the remains. Chase out the threads and you are good to go. Took about a full day, insitu crawling under a vette on a jack so that accounted for time. I just couldn't work laying on my back for a very long time. Work, rest, work rest. Just be very careful to not damage the female threads in the housing.

 

[rgranger]

Instead of going one size larger.... consider filling the hole with JB Weld and tapping that. I've done this on a cracked oil pan and it was still holding 5 years later when I sold it.

 

[dLj]

Instead of going one size larger.... consider filling the hole with JB Weld and tapping that. I've done this on a cracked oil pan and it was still holding 5 years later when I sold it.

JB Weld is an excellent product! This is a great suggestion.

I've done this in the past and totally forgot about this technique.... Thanks for the reminder!

dj

 

[Thaniel]

I believe they are rust welded in there.

Can't visualize what all you have to work with, but to break the "rust weld" you can use some serious heat. Get it glowing red kind of heat and things tend to break loose.

 

[BlowMeAway]

I would go the EZ Out route if you can drill straight into the bolt. Apply some PB Blaster (or similar) early and often before attempting. I would also heat it up with a torch before backing out just to be sure (get it as hot as you dare without destroying anything). Should come right out. Otherwise, it's the more drastice measure mentioned above.

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=video&cd=&ved=2ahUKEwi9jKqd9q7yAhXsKVkFHU_bCP8QtwJ6BAgIEAM&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DcsvDyW8EVvE&usg=AOvVaw3TlTdvOd5n3ER9MGEl-tQj

 

[capta]

First thing I'd do is saturate the bolt remnants in the penetrating oil (I like PB Blaster but I'm going to try Sea Foam Deep Creep Premium Penetrating Oil and Lubricant) on half the nuts I need to get free. I've heard good things about the Deep Creep, although PB Blaster has not failed me yet.
When I say saturate, I mean spraying it 4 or 5 times a day, tapping it gently with a hammer each time. It might take several days of this, but in the end if you have enough bolt to grab with vice grips, you might succeed with more time than labor. A small torch is sometimes handy, heating and cooling the different metals might break the bond.

 

[Kinetic]

Thank you all for the great and detailed replies. Gonna keep at them and hopefully get out of this jam unscathed…. with the exception of boat down time

 

[Daveinet]

Kroil. Kano Labs. Give it time to soak in.

BTY: There is no such thing as an "EZ" out.

You can also try this device:
https://www.lowes.com/pd/SpeedOut-8-1-8-in-Double-Ended-Screw-Extractor/1000170531
The run in your drill backwards, that way when they do catch, they are more prone to back the screw out. Let it soak in Kroil for days.

 

[Tedd]

.... consider filling the hole with JB Weld and tapping that.

Loctite form-a-thread is better for that.

 

[jibes138]

Another option is drill it out, tap the hole and install a stud with two sizes of thread. The larger end goes in the oversize hole the smaller end sticks up through the cover, then a locknut and washer on top. Anybody with a metal lathe with threading capability can make a custom stud quickly. You can buy a stud and then have one end cut to a smaller size thread. McMaster Carr has these, Go to threaded rod then threaded both ends for choices.

 

[MaryEllaRose]

Whatever you do, don’t break the EZ out!
++Kano Kroil
++Left hand drill bit. Start small on center and work your way up in size. If the hole is blind get a bottoming tap.
++Patience

 

[Leeward Rail]

BTY: There is no such thing as an "EZ" out.

100% !

Even moreso when it snaps (as is common) and you now have a hardened steel piece stuck in the hole.


As has already been mentioned:
The create a flat + center punch+ increasing drill sizes+penetrant+heat+left hand drill bit+tap and clean threads method works well.

The trick is to make 100% sure that the hole is dead center. Don't rush the first steps of center punching and drilling.

In some cases, I use an appropriately sized "threaded rod coupler", with a beveled end, as a drill guide.