Y Pipe to Manifold Bolts - Stuck

[chron_bon]

Hi all,

I've been reading a lot of threads here and found some good info about getting the stuck bolts out but I'm wondering if anybody could provide me some input on my situation. I'm doing this on a 1993 4dr 4wd XL.

The ultimate goal is to get the transmission out for a slave cylinder replacement (and clutch/flywheel when I have it out).

I got both the drivers side bolts out relatively easily. Sprayed both sides with Liquid Wrench penetrating oil and let it sit for 5 days then came back to try to get them off. Driver side wasn't much of a hassle, got them both with a 2ft breaker bar and a 20" extension, took about 20 minutes. Passenger side is a whole other story. I've been going at them for 2 days now with the breaker bar and extension and I feel one of them starting to round off so I'm looking for some advice before I destroy the head of the bolts before they come out.

I've tried spraying a lot more penetrating oil and letting it sit, hitting them with a hammer, and heating with a propane torch. I'm not 100% sure they're getting hot enough though.

My questions are this:

1) How hot should I get the manifold near the bolts when heating them with the torch? So far I've been going at it for about 5 minutes with the torch then trying to crack the bolts. I am unsure if this is sufficient.

2) I have an impact that's only 350ft-lbs but can borrow an air powered one but I'm not sure what the torque spec is (the air compressor I believe goes to 100 or 150 pounds). Am I best sticking to my breaker bar or going for the impact? I'm worried the impact doesn't have enough torque and will ruin the bolt heads.

3) I noticed that the two bolts are not threaded in a similar amount. The one nearest to the passenger wheel well goes about 1/2"+ past the end of the manifold whereas the one nearest the engine about 1/8" I'm wondering if whoever installed them last cranked the outermost then the innermost (could be wrong and this is just how they go in normally). I'm thinking that'll make the outermost harder to get, should I focus on the innermost first? Not sure if this is significant but I'm looking for anything that can help.

4) Is cutting the y pipe under the transmission near where the two sides meet then removing the driver side half a reasonable solution? I can't weld it back myself so I would need to find someone who I can pay to come out a weld it back. Any estimates on what that would cost in Canada BC? Are there any options for getting a proper seal if the pipe were cut aside from welding it back?

5) If this goes **** up, how would you cut the bolts? Looks like I can get a sawsall to the one on the wheel well side but what about the other one? This is something I would really like to avoid.

6) Stock height and I don't have a lift, so I believe from my readings on this forum getting the y pipe our from underneath the transmission is my only option. This correct?

Any advice is appreciated.

 

[Roadrunner777]

You might look at nut splitters and see if you have clearance...

You can heat to a dull red, but I don't think you will get there with a utility propane torch... too much thermal mass.

Know anyone with an oxy-acetylene torch? I mean worst case you burn off the nut and replace the stud. Could be your best move would be to get it towed to an exhaust shop and let them buy the headache.

 

[chron_bon]

You might look at nut splitters and see if you have clearance...

You can heat to a dull red, but I don't think you will get there with a utility propane torch... too much thermal mass.

Know anyone with an oxy-acetylene torch? I mean worst case you burn off the nut and replace the stud. Could be your best move would be to get it towed to an exhaust shop and let them buy the headache.

I have one buddy who, I believe, might have one. I was always hoping to cash in a favour and have him help out with this but he's out of town during the COVID-19 pandemic.

When you say heat it that's the manifold not the bolt, right?

If I put a few pieces back together and drove it to a shop would the plan be for them to remove the bolts, add some anti-seize, then I drive it back and remove them immediately? Or is it necessary to have it towed since re-installing the bolts wouldn't help me out much (especially considering their condition).

Thanks for the feedback.

 

[Roadrunner777]

I have one buddy who, I believe, might have one. I was always hoping to cash in a favour and have him help out with this but he's out of town during the COVID-19 pandemic.

When you say heat it that's the manifold not the bolt, right?

If I put a few pieces back together and drove it to a shop would the plan be for them to remove the bolts, add some anti-seize, then I drive it back and remove them immediately? Or is it necessary to have it towed since re-installing the bolts wouldn't help me out much (especially considering their condition).

Thanks for the feedback.

You know, I have been thinking this was a stud in the exhaust manifold and a nut to take off, but you keep saying bolt and it finally clicked that it's bolts threaded into the exhaust manifold in your case. In that case, you would heat the manifold where the bolt threads in.

Anyway, yeah, if you can easily drive it to a muffler shop and just explain you have this big job and you need to get this loose, it's going to be a trivial job for them.

The reason I like this solution is simple. They will have it up on a lift, they can easily see and get to everything and it's what they do every day. And, I'm just not a big fan of using a torch on my back under a vehicle where I don't know exactly where else that heat is going. If I did this, I would probably burn something else in the process and start a fire.

But, if you were to try and continue yourself, I would try and concentrate the heat on the ears of the manifold where the bolt threads in.

Which way to go? Hard to say. You could buy a MAPP torch which would give you much better heat, maybe $60, but then again, a shop would charge you an hour labor and maybe that's $80-$100. Depends on where you are mentally in this, whether you want to conquer this yourself, which I would understand, of if you want to take the easier and maybe cheaper path of a shop. I would call a few shops and see what they say.

 

[410Fortune]

You can grind the heads off the bolts and get the collector apart that way. These are through bolts right? You are talking about that oval shaped thing with the 3 bolts in it? If you do not have access to a torch, just grind them off.

Many transmission shops will just cut your exhaust, R&R the trans, then weld the exhaust back together.

 

[MrQ]

Many transmission shops will just cut your exhaust, R&R the trans, then weld the exhaust back together.

I don't know why they do that. I just take the 4 collector bolts off, remove the O2 sensors, drop the transmission cross member, remove the one bolt holding the exhaust bracket on and the two spring bolts behind the cats, (all which they would have to do anyway to remove the transmission) and just slide it out. Takes me longer to pull the starter. I don't even touch the three bolt flange going to the cats as they are usually rusted on.

Probably an obvious statement, but make sure you are using 6 point sockets on all the exhaust bolts, 12 points are useless and just round the heads off. Plenty of long extensions help you here. The hardest one for me was the upper collector bolt on the passenger side.

 

[chron_bon]

I don't know why they do that. I just take the 4 collector bolts off, remove the O2 sensors, drop the transmission cross member, remove the one bolt holding the exhaust bracket on and the two spring bolts behind the cats, (all which they would have to do anyway to remove the transmission) and just slide it out. Takes me longer to pull the starter. I don't even touch the three bolt flange going to the cats as they are usually rusted on.

Probably an obvious statement, but make sure you are using 6 point sockets on all the exhaust bolts, 12 points are useless and just round the heads off. Plenty of long extensions help you here. The hardest one for me was the upper collector bolt on the passenger side.

I've been using 6 point sockets with a 20" extension and 24" breaker bar. I got the outermost on the passenger side the day after my original post, it was a struggle all the way out. Head is really rounding off on the innermost passenger side, last of the 4 bolts.

I noticed my socket was starting to deform so I switch to another 6 point and it grabbed on better but now is slipping off the last bolt head. Checked it and its also getting deformed but not to the same degree as the first.

I've been letting that last bolt soak since Sunday (today is Friday) and I'm going to go out and buy a new socket to try. I'll also be bringing a hacksaw with me since I don't see this coming out due to the rounded off head. I've got a few plans for what do to if I cut the head off ranging from get the stud out to hack something together.

 

[chron_bon]

You know, I have been thinking this was a stud in the exhaust manifold and a nut to take off, but you keep saying bolt and it finally clicked that it's bolts threaded into the exhaust manifold in your case. In that case, you would heat the manifold where the bolt threads in.

Anyway, yeah, if you can easily drive it to a muffler shop and just explain you have this big job and you need to get this loose, it's going to be a trivial job for them.

The reason I like this solution is simple. They will have it up on a lift, they can easily see and get to everything and it's what they do every day. And, I'm just not a big fan of using a torch on my back under a vehicle where I don't know exactly where else that heat is going. If I did this, I would probably burn something else in the process and start a fire.

But, if you were to try and continue yourself, I would try and concentrate the heat on the ears of the manifold where the bolt threads in.

Which way to go? Hard to say. You could buy a MAPP torch which would give you much better heat, maybe $60, but then again, a shop would charge you an hour labor and maybe that's $80-$100. Depends on where you are mentally in this, whether you want to conquer this yourself, which I would understand, of if you want to take the easier and maybe cheaper path of a shop. I would call a few shops and see what they say.

Sorry about not clarify what bolts I was talking about, you're right, the ones that thread into the manifold from the oval shaped flange.

I'm thinking it's worth calling around. I don't regularly insure this vehicle and getting a day permit here adds on another $40ish dollars which sucks. I would feel a sense of defeat since I've taken out as much as I could in the mean time, including draining fluids.

The goal for doing this myself was to get more experience doing bigger repairs, kill some time and to keep the cost down. I didn't pay much for this vehicle and the rust on the body will probably kill it in the next few years. I use it for camping/adventures on weekends and lending it out to friends for road trips. Couldn't justify paying a shop for the whole repair.

 

[Roadrunner777]

Sorry about not clarify what bolts I was talking about, you're right, the ones that thread into the manifold from the oval shaped flange.

I'm thinking it's worth calling around. I don't regularly insure this vehicle and getting a day permit here adds on another $40ish dollars which sucks. I would feel a sense of defeat since I've taken out as much as I could in the mean time, including draining fluids.

The goal for doing this myself was to get more experience doing bigger repairs, kill some time and to keep the cost down. I didn't pay much for this vehicle and the rust on the body will probably kill it in the next few years. I use it for camping/adventures on weekends and lending it out to friends for road trips. Couldn't justify paying a shop for the whole repair.

Then I would get the manifold ear, where the threads are, as hot as I could with whatever I had available. MAPP gas would be better than propane, and it's darn handy for other things. Then I'd get a 6-point socket on it and pull hard with as much leverage as you can get.

If that doesn't work, then grind/cut off the bolt head and get the y-pipe out. Probably at that point your best move would be to grind the remainder of the bolt flush and drill it out. If you damage threads, you can always back it with a bolt when you put it back together.

it's gonna be a job, but doable.

 

[chron_bon]

Then I would get the manifold ear, where the threads are, as hot as I could with whatever I had available. MAPP gas would be better than propane, and it's darn handy for other things. Then I'd get a 6-point socket on it and pull hard with as much leverage as you can get.

If that doesn't work, then grind/cut off the bolt head and get the y-pipe out. Probably at that point your best move would be to grind the remainder of the bolt flush and drill it out. If you damage threads, you can always back it with a bolt when you put it back together.

it's gonna be a job, but doable.

Thanks for the tips! I gave it one last shot with a brand new hardened socket and managed to get it out. I heated the ear for about 10 minutes, with propane, then hit with with penetrating oil for good measure and went to work. I thought I had fully rounded the bolt head when I tried loosening it after heating it and got back up to grab the hacksaw. It felt bad, like it was spinning in the socket, hard to describe the feeling. When I got up and looked in the wheel well at the working area to cut the head off I noticed it has actually started to unthread. Felt mushy the whole way out but it's out!

I can now continue and pull out the transmission. Thanks a lot for your tips and the tips everyone gave in this thread. This forum has been a great source of knowledge. I hope to be able to give back to the pool of knowledge one day.

 

[Centaurious]

When you put this back together I would install studs in all 4 holes and use heavy BRASS nuts to secure the flanges. This gives you or others the best chance of not having your current fight all over again.

 

[Roadrunner777]

Thanks for the tips! I gave it one last shot with a brand new hardened socket and managed to get it out. I heated the ear for about 10 minutes, with propane, then hit with with penetrating oil for good measure and went to work. I thought I had fully rounded the bolt head when I tried loosening it after heating it and got back up to grab the hacksaw. It felt bad, like it was spinning in the socket, hard to describe the feeling. When I got up and looked in the wheel well at the working area to cut the head off I noticed it has actually started to unthread. Felt mushy the whole way out but it's out!

I can now continue and pull out the transmission. Thanks a lot for your tips and the tips everyone gave in this thread. This forum has been a great source of knowledge. I hope to be able to give back to the pool of knowledge one day.

The gods of rust looked favorably on you.... good work! At some point down the road, you should get a tap and chase the threads in the manifold, new bolts of course, and a high-temperature anti-seize... not regular, there's special anti-seize for high temperature use. If you can find stainless 316 for the bolts, that would be ideal... maybe overkill, depends on whether you think you will be on this road again in 5-10 years, which would not be unheard of for a vehicle with a clutch. That new socket was key. If I had a barrel of cash I would replace my entire set with 6-point hardened.

 

[judson1896]

Does anyone know the size and thread pitch for the original bolts from y pipe into the manifold?

 

[chron_bon]

Does anyone know the size and thread pitch for the original bolts from y pipe into the manifold?

I know they're M12x1.75, looks like 45mm long, maybe 50mm.

The flange head is smaller than a typical M12 hex flange bolt, I opted to buy new ones from Ford. Cost me $8 CDN each.

 

[RangerX]

I know they're M12x1.75, looks like 45mm long, maybe 50mm.

The flange head is smaller than a typical M12 hex flange bolt, I opted to buy new ones from Ford. Cost me $8 CDN each.

Wow, surprised the dealer carried them!
If you could, please post the part number, I may be needing some in a few weeks when I do my clutch.