Sheared y-pipe bolts

**Black Dragon WS6** · 10-12-2020, 05:24 PM

Sheared off Y-pipe bolts removing from the cat end down pipes. How do I get the old bolt out of the cat section to replace the bolts between the Y and the cats? Do I beat them out, or do I try to screw them out? Stock exhaust currently. Thanks much for the assistance. Car's been sitting for a long time. Just getting back in the game is why I've not posted in long time.

**DarrenWS6** · 10-24-2020, 09:36 AM

Originally Posted by Black Dragon WS6

Sheared off Y-pipe bolts removing from the cat end down pipes. How do I get the old bolt out of the cat section to replace the bolts between the Y and the cats? Do I beat them out, or do I try to screw them out? Stock exhaust currently. Thanks much for the assistance. Car's been sitting for a long time. Just getting back in the game is why I've not posted in long time.

Take a wire wheel to the surfaces and threads to clean them up. If there is anything protruding out, try to weld a nut on. Once welded on, try and heat the surrounding area, not the stud itself, and attempt to work it out. Back and forth motions to free it up.

If there is nothing protruding, you may be left to drill the stud out and re-tap a thread into it if you intend to ever re-use the cat.

**Black Dragon WS6** · 10-25-2020, 06:27 AM

Much appreciated DarrenWS6. Plenty of bolt still sticking out. Will try the clean and heat method you suggest. Got distracted by Diff fluid change and finishing clutch install. Again, thanks for the advice!

**Black Dragon WS6** · 11-29-2020, 04:08 PM

Conclusion: Tried the "clean up and heat" method. Couldn't ever get the locking pliers to turn the bolts out. Didn't have access to welder to attach new nut on bolt/stud to turn it out. Finally, just Dremel cut them off as flush as possible, sanded, and then used pyramid shaped attachment on Dremel to get a starting depression in center of bolt face. Used a really good drill with really good bits, and step-wise drilled them out.

I think I preserved the threads in the cat side of flange, but didn't worry about it. Just stuck long bolts through with lock washers and tightened up hard. Maybe I'll have problems later, but with way the Y-pipe and cat side flange meet, they just need to kiss tightly, and I have no exhaust leak thus far.

**oldmanZ28** · 11-30-2020, 05:02 AM

From the post, sounds like rust was the culprit. The use of a stainless steel bolt, available in both SAE and metric, will prevent future problems. A standard grade SS bolt is stronger than a grade 5 SAE, so they're pretty strong to start with. Here in the 'rust belt' of NE Ohio, I use SS wherever I can. BUT never use a SS bolt and SS nut together, one of them has to be non-SS, SS to SS will seize/weld together with high torque.

**Black Dragon WS6** · 11-30-2020, 05:33 AM

Originally Posted by oldmanZ28

From the post, sounds like rust was the culprit. The use of a stainless steel bolt, available in both SAE and metric, will prevent future problems. A standard grade SS bolt is stronger than a grade 5 SAE, so they're pretty strong to start with. Here in the 'rust belt' of NE Ohio, I use SS wherever I can. BUT never use a SS bolt and SS nut together, one of them has to be non-SS, SS to SS will seize/weld together with high torque.

After 19 years, I'm sure you are correct on the 'rust' diagnosis. Advice is much appreciated. Will ensure I replace in that configuration. Have a great day!

**oldmanZ28** · 11-30-2020, 06:06 AM

Whenever I go to the big Canfield auto swap meet (and home depot too),I add to my SS fastener collection.
Lot of the engine bay 6mm bolts are now SS. Rear end cover (SAE 5/16), driveshaft tunnel crossbrace (8mm), rear shock lower mounting nut, bolt-in subframe connectors (SAE 7/16), and many others are now SS. I also re-did the entire rear brake system from in the tunnel to the calipers with SS tubing w/ -3AN connectors and got rid of all those factory fittings.

**desmond** · 11-30-2020, 03:05 PM

Originally Posted by oldmanZ28

From the post, sounds like rust was the culprit. The use of a stainless steel bolt, available in both SAE and metric, will prevent future problems. A standard grade SS bolt is stronger than a grade 5 SAE, so they're pretty strong to start with. Here in the 'rust belt' of NE Ohio, I use SS wherever I can. BUT never use a SS bolt and SS nut together, one of them has to be non-SS, SS to SS will seize/weld together with high torque.

We'll be dealing with rusted bolts on buddy's Camaro project soon after we finished installing the parts from 4Wheelonline onto the truck. We'll definitely consider stainless bolts.