How to drill through rusted exhaust bolts?

Can seem to get drill through some rusted bolts on the exhaust flanges. The flange right after the 2nd cat, figured I’d be able to drill through them no problem since they were falling apart in my hands. I’ve been a grinder to take off the shank and head of the bolt and titanium drill bits just won’t budge it. Any tips would be greatly appreciated.

 

I had the same problem. Not in the same place at you, but still on an exhaust flange. Spent close to two hours working on the damn thing. I ended up drilling half through the bolt and half through the flange. I was then able to pry what was left of the bolt out. Cleaned up the hole with a bigger drill bit, and used a bigger bolt and nut to reassemble. Not the prettiest of jobs, but it holds.

 

Yeah that’s exactly what I’m trying to do but I just don’t think the drill bit is going to cut anymore. It drilled through I guess most of the rusted head and now it’s just not budging on some harder shank of the bolt. Might just end up taking it to a muffler shop and getting them the chop out the flange and weld some pipe in.

 

Snap them off .

 

I bet a new and sharp cobalt drill bit should go through the bolt at a reasonable rate.

 

You cannot drill through them going quickly. Slower is better with sharp, new bits.

 

Can you use a reciprocating saw (Saw-zall) and cut between the two flanges and cut the bolt in half?

 

The constant thermal cycling makes those bolts hard.

You are keeping the drill bit cool using cheap spray lube..

If the nuts have been cut off Air Hammer with the correct size punch should pop them out

 

Yeah, you have to keep the drill bit oiled or it will overheat and become dull. One of the few things I remember from metal shop class in 8th grade so looooong ago.

 

You'll ruin the flange. Drill drill drill.

 

Myself if I could not get them apart in 30 minutes Time for new flanges and done.

They are bolts and nuts not like your trying to drill out studs.

The only thing holding them is the rust heat and impact should get them out.

Unless some idiot used loktite then your going to need heat.