exhaust studs on down pipe 280z

[Dave WM]

after snapping one off (and deciding to call it quits before I do any more damage) I decided to try the nut splitter on the brass nut from the snapped off one. No joy with hand tools but with an impact driver it split that baby in seconds, then it came of real easy.

Now the issue is how to get the impact driver on the nut splitter with everything installed and not loose out it the open. I am pretty sure the back the middle one with a swivel joint and extension with the windshield washer door up you could do, the other may be more of a challenge.

just FYI. I plan to take it too a shop at this point since my confidence has been shaken. I presume the correct approach is oxy/acty torch.

[Zed Head]

5 minutes ago, Dave WM said:

after snapping one off (and deciding to call it quits before I do any more damage) I decided to try the nut splitter on the brass nut from the snapped off one. No joy with hand tools but with an impact driver it split that baby in seconds, then it came of real easy.

Now the issue is how to get the impact driver on the nut splitter with everything installed and not loose out it the open. I am pretty sure the back the middle one with a swivel joint and extension with the windshield washer door up you could do, the other may be more of a challenge.

No offense, I understood the first paragraph - you used a nut splitter on an exhaust stud to avoid breaking a stud.  That sounds like a great recommendation for anyone who is worried about that and seems wothwhile

But I can't get a meaning out of the second paragraph.  I'm sure the thought was clear in your head but it didn't make it in to the words.  This sentence just twisted my brain - "I am pretty sure the back the middle one with a swivel joint and extension with the windshield washer door up you could do, the other may be more of a challenge".

[Dave WM]

I used the nut splitter AFTER I snapped of and had it on the bench.

as installed getting the splitter on is still possible but getting the impact driver hooked up no so easy. It get real cramped in that space by the time you get the splitter on (its about 3-4" long, then the impact socket, so you have to try to figure out a combo that fits and lets you get the impact driver on it as well.

Of the 3 nuts on the down pipe, the middle one seems the best shot, the back not so easy and the front I cant really tell since it was the one that was broken off.

 

Edited March 6, 2017 by Dave WM

[Zed Head]

I see.  I like the idea of just sacrificing a nut over taking a chance on the stud.  I bought a wrecking yard manifold as a spare and spent a lot of time and effort removing a broken stud and that was on the bench, with a torch, and PB Blaster, and a hole drilled through to get the Blaster in behind, and good leverage.  It was kind of incredible how stuck if t was.  It would only budge when the manifold was hot.

I wonder if a cutoff wheel would be easier.  Cut up what you can reach and chisel off the rest.  Or maybe a different type of nut-buster.  I don't know what's out there.

I still have a nut stuck on a stud that I use as a bolt on my currently in-use exhaust manifold.  It all went together right in the beginning but later the nut and stud came out together.  I just use them in the hole they came out of that way.

[Dave WM]

the dremel may work, doubt you could get the cut full length of the nut due to the manifold getting in the way, but I bet you could get 3/4 of it any way then use the nut splitter to open it up with out the need for power tools.

[One Way]

Is there enough stud to weld on a nut to the end?  That may work but the oxy/acetylene option is usually the best approach to start with before snapping anything off.  A few heat and cool cycles will usually be needed but it will work for getting those studs out.  Good luck, John-Lugoff, SC.

[Dave WM]

maybe once I get the manifold off will have a better idea (weld nut to stud).

I did buy some reverse drill bits if case I have to drill it out.

looking into the Oxy/Ace torch for the other 2 that are still in.

while looking into that, I decided to try one more thing. I have a small cap filled with evap o rust (great product) that the stud is soaking in. I used a magnet to hold it in place while it works its way into the stud/nut, figured it can hurt.

[7tooZ]

I drilled mine out. Retapped the hole for the stud or for a larger stud. You can purchase a stud with two different size threads if needed. Still working after 10 years and many downpipe removals.

[Dave WM]

5 minutes ago, 7tooZ said:

I drilled mine out. Retapped the hole for the stud or for a larger stud. You can purchase a stud with two different size threads if needed. Still working after 10 years and many downpipe removals.

Good to know. I was pretty bummed out when I realized it was broke.

[JSM]

1 hour ago, Dave WM said:

maybe once I get the manifold off will have a better idea (weld nut to stud).

I did buy some reverse drill bits if case I have to drill it out.

looking into the Oxy/Ace torch for the other 2 that are still in.

while looking into that, I decided to try one more thing. I have a small cap filled with evap o rust (great product) that the stud is soaking in. I used a magnet to hold it in place while it works its way into the stud/nut, figured it can hurt.

Do you need a torch?

[Dave WM]

think I am going to need the torch, I bought a POC little thing, while it got hot and I managed to get about 1/8 of a turn then snap. So next up on the remaining ONE stud will be to use JSM big torch and try one more time. After that I am hoping I can weld a nut on the two broken ones.

I took it to a shop, 500$ to R&R the manifold for drilling and tapping. 45$ if I just bring them the manifold. I like that idea but am afraid of breaking more bolts as I get into the studs that attach to the alum, head. I assume torching the bolts to get them hot is NOT a good idea here due to the alum head (heat transfer to head).

The shop did not want to drill the manifold down pipe due to location (hard to get a drill up by the oil pan). Hence the need to pull the manifold off.

So options

1. Pay the man to RR the manifolds figure with parts etc I can easy get to 750$ just to fix the 3 studs.
2. Try the cherry red heat on the remaining one, if I can get it out, then assess the two brokens for possible welding on of a nut and then re heat to cherry red and try those.
3. remove manifolds, take to the man for the drilling and tapping.
4. do nothing, add oil every 200 miles (leaking main), wait for a slipping clutch to force the issue.

I am leaning towards opt 2 since I would have to disconnect the down pipe anyway if I wanted to remove the exhaust. If I did not think the manifold bolt were going to break I would just do that and know I have a good new gasket. Oh and there is that broken bolt on the back of the head where the engine hoist mount goes, Maybe I could fix that as well IF I go with opt 3.

Taking a break from it for a while. Funny thing is one place quoted me 60$ per broken bolt if I let them do the clutch/rear main/trans swap. That I guess is opt 5 and is looking pretty good. I just don't know how they can only charge 60$ unless they drill it in place, and if that is the case why the one shop would not do that? I guess the 60$ broken bolt shop figure they can do the drilling regardless of location?

 

 

 

 

Edited March 27, 2017 by Dave WM

[JSM]

From my experience with removing head nuts / bolts is that they normally come out pretty easy.  Just be sure to save those thick washers.  If you need some let me know I have plenty of extras.

So now you have two of the 3 broken?

Let me know if you need the torch.