Flange bolts, any tips?

[exzachtly1]

Got a new (used) OEM exhaust to replace my crappy rusted out one this week. Decided to take a stab at removing the flange bolts tonight to see what kind of trouble I was in. After reading around a lot, I decided to try CRC freeze-off first... had a lot of good recommendations. Used it as instructed and snapped the first bolt I tried. I have never done this, and I was quite surprised at how little torque it took to break that bolt. I doubt these have ever been off.

I tried the second one, but stopped as it was not budging. Thankfully the first is sticking out by 1/2" or so, so I think I should be able to get it off with some pliers or by slotting it and using my impact driver once the pipes are off.

So... my plan is to go get a map gas torch, some locking pliers, and a candle, and try alternating heat + pb blaster and melted candle wax for a few rounds. I just doused all of the bolts with pb blaster to soak over night. I also tapped all of them with a hammer, but am not sure how hard I should really be hitting them so I did it fairly lightly.

I've read many of the threads about this problem, but does anyone have any more advice / proven methods before I go breaking all of the bolts? Right now I'm just bummed that my bike is basically out of commission until I get this taken care of. This is why I need a second bike, but my wife will never buy that

 

[Guest]

See how they feel when the motor is up to operating temperature. I always remove mine with a hot motor and then use anti seize compound on the bolts so they never get stuck. You may need to work them in and out a bit, but never force them if they don't cooperate. Given time the PB Blaster should start to creep into the threads.

 

[exzachtly1]

See how they feel when the motor is up to operating temperature. I always remove mine with a hot motor and then use anti seize compound on the bolts so they never get stuck. You may need to work them in and out a bit, but never force them if they don't cooperate. Given time the PB Blaster should start to creep into the threads.

I thought about trying with the motor hot. Maybe get it nice and toasty, then spray with PB and hope it sucks in better as the motor cools. I'll give it a try tomorrow. That first bolt really did take me by surprise with how easily it broke.

Would my impact driver (hand, not power) make sense in this situation? I believe it can accept 1/2" sockets, so maybe I can try that too... Seems like that would have less risk of breaking the bolt by over torque-ing.

And yes I have new bolts (and studs, not sure which to use yet) and plan on lots of anti seize when I install.

 

[SqDancerLynn1]

Try just whacking it with a hammer first to shock it..

 

[ThrottleBack]

For future reference never remove any bolt related to any exhaust without using a torch to heat the area around the bolt and expand the threads. ever. seriously never ever.

Thread on two nuts, then back the inside nut out against the outside nut. Get it torched up good and hot then use the inside nut to turn it out.

 

[tkent02]

For future reference never remove any bolt related to any exhaust without using a torch to heat the area around the bolt and expand the threads. ever. seriously never ever.

Thread on two nuts, then back the inside nut out against the outside nut. Get it torched up good and hot then use the inside nut to turn it out.

Weld a nut in place on it, turn it out while it's still fairly hot. Wax is good, it will melt and slide down the threads to lube it up good.

 

[ThrottleBack]

welding it on works too

 

[bwringer]

Never never never never never NEVER NEVER NEVER even think about contemplating the merest possibility of considering an easy-out or any sort of extractor.

It WILL break off.



Welding a nut onto the stub has the highest chance of success.

Apply Kroil, candle wax, or a 50/50 mix of ATF and acetone. PB Blaster and WD-40 are pretty much useless for dealing with stuck threads.

 

[exzachtly1]

Thanks for the advice guys. I will never use an ez-out on these, so no worries there.

I got two of them off this morning after heating the engine up, but broke one more so now I have 2 that are broken (broke in the same place as the other one); I guess I got cocky but it is really hard to tell the difference between turning and breaking on these. Now that I have successfully removed 2 I think I know what it should feel like. Definitely was a noticeable "snap" when the corrosion broke. What seemed to give the most success was a slight tighten, then loosen, going a little further each time.

Needless to say, I will be proceeding with extreme caution at this point.

Regarding heating, do you all think that the heat from running the engine is sufficient, or should I be torching? All I have is propane, do I want map gas for this?

Trying to focus on technique for getting the last 4 off without breaking, then I will only have 2 broken ones to deal with. There should be enough thread on them to get 2 nuts on; though one is a bit mangled from an initial attempt with pliers so we'll see... hopefully I can still force a nut on there.

 

[exzachtly1]

Oh... also I don't have any welding experience or equipment so unfortunately that's not really an option for me.

The good news is that the threads that are below the surface of the head barely have any corrosion (as far as I can tell from the 2 that came out). The weak point seems to be near the end of the bolt. That's where the two broken ones twisted off.

 

[Nessism]

PB Blaster and heat are the trick. Also, use a short handle 1/4" ratchet wrench so you don't overpower the screw. Spray the screw then heat it red hot. Repeat as necessary. Turn the screw both in and out until it cracks loose. Once you get it to move, keep working it back and forth with lots of PB Blaster and it will slowly turn further and further until it comes out.

 

[exzachtly1]

PB Blaster and heat are the trick. Also, use a short handle 1/4" ratchet wrench so you don't overpower the screw. Spray the screw then heat it red hot. Repeat as necessary. Turn the screw both in and out until it cracks loose. Once you get it to move, keep working it back and forth with lots of PB Blaster and it will slowly turn further and further until it comes out.

Cool. I'll have to pick up a smaller ratchet, right now I am using a 3/8 with a 1/4 adapter; probably too easy to over torque.

Now - you say to heat the bolt; but others say to heat the area around the bolt; which is best, or does it matter?

 

[Nessism]

Heat the bolt. Spray lots of penetrating oil, both before and after the bolt is hot. Once you get the bolt to crack loose, even just a little, there will be more room around threads for the oil to wick down into. Keep working the bolt both in and out until it turns all the way out.

 

[Guest]

Also use your thumb and third finger on the 1/4" ratchet. It will limit your ability to break things and teach you a better "feel" for what you are doing. And after that and anti-seize compound where alunimum and steel is concerned, there is torque wrenches. You'll probably never break a bolt again.

 

[exzachtly1]

Also use your thumb and third finger on the 1/4" ratchet. It will limit your ability to break things and teach you a better "feel" for what you are doing. And after that and anti-seize compound where alunimum and steel is concerned, there is torque wrenches. You'll probably never break a bolt again.

I think you're right, even after just these 4 I think I am getting a good feel for it. At least a good sense of what NOT to do, haha. Hoping for some good progress tonight. Will probably have a buddy over for moral support too.

 

[ThrottleBack]

BTW engine heat is not sufficient.

I say heat the area around the bolt because i don't like to apply the heat directly to the bolt. Heating around the bolt has the same effect so it's just personal preference.

 

[Guest]

The aluminum will take plenty enough heat from a heated bolt to expand because of it's heat conduction characteristics. I would lean toward heating the bolt. A warm engine is not enough if the bolts are stuck, but after they are loosened and coated with anti-seize it will make it a lot easier. I have an old Vance and Hines 4-1 that I regularly remove for painting when any rust shows up because it was badly pitted to begin with. Heating the motor to operating temperature makes the bolts glide out.

 

[Guest]

Will probably have a buddy over for moral support too.

Put him to work... one of you can man the torch, the other using the PB Blaster & wrench/vise grips.

Couple of things going on when using heat to break those buggers free:

First, the galvanic cell that created the corrosion between the two dissimilar metals (carbon steel bolt/aluminum head) is largely a chemical bond. High heat (not engine heat) will help to break that bond.

Second, the two different metals each have different thermal coefficients of expansion, meaning they each expand at different rates. When hot, the aluminum will expand a bit more than the steel & essentially ?release? its hold on the bolt.

BTW, I would use MAP gas because it's hotter; the mass of that aluminum head makes for a very good heat sink so you need to apply lots of heat to get it hot enough to work. Heat the bolt where it enters the head & don?t worry about melting the aluminum?

Follow Ed?s advice & take your time. Good to have a fire extinguisher handy as well, just in case!

Good luck

 

[exzachtly1]

Whelp, feeling fairly defeated now. Another bolt broken and 3 still on there that won't budge. So the count is 3 broken, 2 removed, 3 still on.

I didn't get the map gas because I didn't realize it would be $50 to purchase the gas + attachment. Figured I could make do with propane. Did many cycles of PB, heat, candle wax, tapping with a hammer, tried running the bike to get the engine hot. Used a shorter 1/4" socket driver as suggested.

The 3rd broken bolt is broken pretty close to the head, not flush but sticking out maybe 1mm or so.

At this point I don't want to mess with the last 3. Like many jobs of this nature, I'm finding myself in a position where I'm weighing the costs between just taking it somewhere vs. buying all the tools I'm gonna need to deal with this. The way I see it at this point is I will at least need:

Map gas for heating if I'm going to attempt the last 3 bolts
Dremel, if I need to slot the broken bolts
Drill bits if I need to drill out
Tap & die / Heli-coils for making new threads
etc...

figuring around a couple hundred bucks to do it the right way. For something I may only do once in my life.

What do you guys think... if I take it somewhere, is the better option to ride the bike in while it's still rideable (exhaust roughly attached still), or plan on just finishing the bolt mangling and taking the head off to go to a machine shop. What's the better option? I'm feeling like the last 3 bolts are a lost cause. I don't know why the two on #1 came off so easily and the rest are being so crappy...

 

[ThrottleBack]

those are all tools you will inevitably need anyway.

tools = investment

shop = flushing