EGR Block Off FUBAR

[Goldbug]

I took goldbug on a trip to Block Island last week and on the way home, it started sounding like someone had removed the exhaust. Turns out, the EGR block off plate was loose. I happened to purchase one from Jim C when I first got her and had him rebuild my carb. So I went to swap it out...

I thought it was loosening the nut on the stud but actually sheared the stud off. (One on the left). I now have a stud I need to remove that doesn't want to move, and in a very awkward tight spot.

Does anyone have an artful way to remove the stud? If I can't, I'm worried it will be very difficult to accurately drill it out, and will require moving the exhaust, which could open another can of worms. I've been hitting it with PB blaster every day for a few days now.

 

[bhsdriller]

I'd pull it and do it on the bench to not risk it breaking even further. Will be a lot harder if it snaps again flush with the manifold

 

[45Dougal]

Wind a nut onto the stud and then weld it in place on the end?
Enough heat should free it and with a good socket on there he might just jump out

 

[Malleus]

At this point, I resort to harsh language...and a lot of it.

 

[Goldbug]

Yes to all the above. Don’t have a welder but maybe I’ll see if I can borrow one. 5 minute job became hours of torment. Argh!!

 

[45Dougal]

Or don't remove it just yet.. Could you drill the hole in the plate out to bigger size and fit a tubular tapped spacer or "connecting nut" onto the stud?
I see m8 in A2 stainless have an 11mm outside diameter - not sure if your plate has enough meat on it for that.
Cut it to the right length and fit a bolt - might need a spacer too so it will be messy, but gets you back on the road until you have the engine on the bench at least.

 

[Goldbug]

Or don't remove it just yet.. Could you drill the hole in the plate out to bigger size and fit a tubular tapped spacer or "connecting nut" onto the stud?
I see m8 in A2 stainless have an 11mm outside diameter - not sure if your plate has enough meat on it for that.
Cut it to the right length and fit a bolt - might need a spacer too so it will be messy, but gets you back on the road until you have the engine on the bench at least.

Didn’t see this until I did this:

 

[Goldbug]

I heated it and tried to get it to budge but I think the stud was already partially sheared. Gonna hit it with a punch and try to drill it out. Looks like a straight shot from below if I have a long enough bit or extension.

The journey continues…

 

[45Dougal]

Bugger. Yea probably already fractured.
At least the manifold isn't aluminium.
Maybe you can make up a thick plate with two holes, and hold it in place with one nut as a drilling guide?
I'd try with a good Centre Drill to get it started.

 

[sogncab]

Pull the manifold. Don't worry about it creating other problems, it will.

A channel on YouTube I watch, it's an engine machine shop. He's freed a lot of broken studs welding nuts on. The heat cycle and something to grab seems to work well.

Put everything back together with anti-seize.

 

[Goldbug]

Bugger. Yea probably already fractured.
At least the manifold isn't aluminium.
Maybe you can make up a thick plate with two holes, and hold it in place with one nut as a drilling guide?
I'd try with a good Centre Drill to get it started.

What's a Centre Drill? Even translated to American, not sure what a Center Drill is...

Was gonna pick up some nice new bits this morning. Also dove deep into the microfiche on partsouq here to find the right stud part no: 92122-60818

Good idea on creating a drilling guide too

 

[45Dougal]

What's a Centre Drill? Even translated to American, not sure what a Center Drill is...

Was gonna pick up some nice new bits this morning. Also dove deep into the microfiche on partsouq here to find the right stud part no: 92122-60818

Good idea on creating a drilling guide too

When you're turning a part on a lathe, you start the hole with one of these to avoid pushing it off centre. Small starting hole but also strong enough not to snap immediately

 

[Goldbug]

Taking it slow, making good progress so far. Patience is not one of my virtues, but this thing keeps teaching me lessons.

 

[bikersmurf]

You're making good progress. with a little luck it'll spin right out as you get close to the inner bore...

My luck, unfortunately, would be that I'd be a hair off center and the remnants of the threads would shift just enough to jam the bit, it'd break off, and then I'd be fighting to extract a broken off bit. Or even worse cracking out the corner of the manifold tab... be careful and take it slow and you should be fine.

I have had good luck getting out broken bits/extractors by heating them till they were cherry red, and grabbing them with vice grips before they cooled down much, and then turning and pulling them out.

 

[ceylonfj40nut]

Gradually bore out wider. Then insert easy out and turn. If the bolt wall thickness left is thin. It will collapse enough to dislodge.

 

[Goldbug]

Gradually bore out wider. Then insert easy out and turn. If the bolt wall thickness left is thin. It will collapse enough to dislodge.

I was hoping that would work but couldn’t get it to. Haven’t had a lot of luck with them. But persistence and patience paid off. I very gradually increased the bit size and then tapped it out. Got the new Jim C block off plate in there and sounds great again!

Just in time for 4th of July parades too

 

[45Dougal]

Great job, and nice follow up pictures too

 

[JMZ400]

Thanks for the inspiration. I too have to tackle this job but I'm super paranoid about breaking one off.