Wildguzzi.com

General Category => General Discussion => Topic started by: moto on July 22, 2021, 03:09:46 PM

Title: How to separate long-connected exhaust pipes?
Post by: moto on July 22, 2021, 03:09:46 PM
For the last 20 years I've never separated the right-side downpipe from the crossover on my T3. They were stuck when I bought it. Now I have a reason to separate them.

Soaking with PV PB Blaster and tugging isn't working. What's the secret?

Moto
Title: Re: How to separate corroded exhaust pipes?
Post by: tris on July 22, 2021, 03:12:17 PM
Heat, and possibly a lot of it, shifts most things after a couple of cycles

Be aware of fuel,  cables and anything else that might burst into flames
Title: Re: How to separate long-connected exhaust pipes?
Post by: Antietam Classic Cycle on July 22, 2021, 04:00:35 PM
Heat, penetrating fluid of your choice, lots of foul language and of course... a BFH.  :wink: Good luck...
Title: Re: How to separate long-connected exhaust pipes?
Post by: fotoguzzi on July 22, 2021, 04:12:56 PM
Hacksaw... they probably won't work too good after tho.
Title: Re: How to separate long-connected exhaust pipes?
Post by: Chuck in Indiana on July 22, 2021, 04:15:38 PM
 :popcorn: I have a pair of Milich Special rusty Bubs on the AeroLario. I'd really like to get them apart to repack them, but so far no joy.
Title: Re: How to separate long-connected exhaust pipes?
Post by: RinkRat II on July 22, 2021, 05:34:20 PM

   It will take a good deal of finesse so as to not damage the pipe, but you can try the two hammer method. Using a small ball pein as backup against the pipe, strike the pipe gently  on the opposite side that your holding the first hammer against. Working your way around the pipe , the idea is to just stretch the metal and loosen the corrosion . Easy does it .

      Paul B :boozing:
Title: Re: How to separate long-connected exhaust pipes?
Post by: ozarquebus on July 22, 2021, 06:57:10 PM
I removed the entire exhaust system in one piece which made all of the methods described here much easier.
Title: Re: How to separate long-connected exhaust pipes?
Post by: Shorty on July 22, 2021, 10:45:51 PM
A good soak in aerokroil. Then get a small block of wood and a rivet gun or air chisel with a flat tool or flush rivet set with an air  reducer valve. Put the wood against the end of the pipe or muffler. Gently drive (with the rivet gun) the pipe in the opposite (on) direction you want it to go. This breaks (hopefully) the rust adhesion. Squirt more spray into the seam and let it soak. Repeat the process. Use a small hard piece of wood to drive it back where it was. After it is semi loose, get a shop towel and a pipe wrench to work the pipe back and forth til you can drive it off with the wooden chisel.
Title: Re: How to separate long-connected exhaust pipes?
Post by: Scout63 on July 22, 2021, 11:40:35 PM
1. Order that new set of pipes you’ve always wanted.
2. Remove the old set in one piece after hanging it up on the center stand and front wheel for 40 minutes and snapping off at least one exhaust port stud.
3. Put the old set in the garage where you will trip over it for two years before taking it to the town recycling pile.
4. Rebuild the entire motorcycle around the new shiny pipes.
5. Post every step of the process.
6. Spend six months sorting the bike.
7. See an interesting wreck in someone’s garage, buy it for a song and sell the perfectly restored Guzzi for 60% of the parts cost.
Title: Re: How to separate long-connected exhaust pipes?
Post by: Turin on July 23, 2021, 12:26:03 AM
removing as one piece is your best bet. how bad are they?
Title: Re: How to separate long-connected exhaust pipes?
Post by: 9fingers on July 23, 2021, 05:56:59 AM
Someone mentioned Kroil penetrating oil and that is what I use on guns, great stuff! Let that soak in for a couple days and then hit the are with a rubber mallet a few times and then try. If that doesn't work use heat and if that doesn't work you are on your own. Good luck!
Scott
Title: Re: How to separate long-connected exhaust pipes?
Post by: SIR REAL ED on July 23, 2021, 07:16:28 AM
Heat, penetrating fluid of your choice, lots of foul language and of course... a BFH.  :wink: Good luck...

yep!  It pays to study at the feet of the masters!!!!

and whatever you do, don't put a "g" on the end of your favorite curse words.
Title: Re: How to separate long-connected exhaust pipes?
Post by: jwinwi on July 23, 2021, 07:48:12 AM
For the last 20 years I've never separated the right-side downpipe from the crossover on my T3. They were stuck when I bought it. Now I have a reason to separate them.

Soaking with PV Blaster and tugging isn't working. What's the secret?

Moto

What you need is PB Blaster; much stronger than PV. :evil:
Title: Re: How to separate long-connected exhaust pipes?
Post by: moto on July 23, 2021, 01:24:21 PM
Hmm. Thanks to several for sincere suggestions. The methods now on the table, alone or in combination, are:

1) soak
2) heat
3) the two hammer method (Paul B, aka RinkRat II)
4) chisel from the end of the outside pipe, after first hammering the joint together (Shorty)
5) relocate the clamp to below the joint and hammer on it instead of the pipe end
6) ratchet strap and a golf cart, or "how to remove a stuck exhaust Grumman style"

I found (5) on Youtube, being performed on a Ford car exhaust: https://www.youtube.com/watch?v=uBW411D8UUM (https://www.youtube.com/watch?v=uBW411D8UUM).

Number (6) is here, performed on an airplane: https://www.youtube.com/watch?v=s8RK9icStf4 (https://www.youtube.com/watch?v=s8RK9icStf4). It basically adds a ratchet strap for pulling after (1) and (2).

Two things that differentiate my T3 exhaust from the Ford and Grumman examples is the longer overlap of the joint, about 1 1/2 inch, and twenty years of bonding.

The two hammer method is indeed "a thing": I found it used to remove tie rod ends and to get nuts off of bolts (on the internet). I am impressed by the specificity of Paul B's advice, in the use of a small ball peen hammer on one side and "striking gently" on the other. Paul, have you successfully used this method on exhaust pipes? I've been trying, but no luck so far. I'll keep trying. I REALLY like the "Easy does it" admonition at the end of your post. That's my very favorite level of effort!

To clarify, I'm not particularly desperate here. The crossover-exhaust header combination is off the bike, and I don't plan to reuse either part, though I might pass one or both downstream to someone in greater need. It's a mixture of pride and OCD for me to separate them. The first is a sin and the second a disease. Maybe I'll snap out of it.

Thanks, all.

Moto



Title: Re: How to separate long-connected exhaust pipes?
Post by: bmc5733946 on July 23, 2021, 01:49:39 PM
My advice is to heat it cherry red then cool it rapidly with a water hose, it will probably slip apart then, if not repeat until it does. Your finish may not survive if that matters.. Learned this at the feet of a master, works with nuts and bolts as well. I've told many people about this, few believers. Those who have witnessed it are believers. First time I saw it it was a bleeder in a steel caliper, after heating and cooling it broke loose with very little pressure from a wrench and unscrewed with my fingers, simply amazing, like magic and I ain't no magician!

Brian

Title: Re: How to separate long-connected exhaust pipes?
Post by: Guzzistajohn on July 23, 2021, 02:02:02 PM
We used PB Blaster on pee soaked wheelchair bolts when I was in rehab equipment repair. That shit WORKS! We called it panther piss  :grin:
Title: Re: How to separate long-connected exhaust pipes?
Post by: tris on July 23, 2021, 02:14:33 PM
My advice is to heat it cherry red ................

Brian
First time I saw it done was by the shipyard Shipwright Foreman where I first worked
We had a RFA ship come in for a refit, and they couldn't secure the hatch properly because one of the 1 inch securing   bolts was seized

Oxy/Propane to bright cherry red and an air chisel got normal service back sharpish

Title: Re: How to separate long-connected exhaust pipes?
Post by: RinkRat II on July 23, 2021, 02:18:57 PM
  Moto, as a millwright for 35 years I've used that technique for just about every type of stuck apparatus man made. The level of force is dependent on the ability of access and if your trying to re use the part.  I've also used the cherry red method, but that will change the appearance of the item.  Keep soaking too!

       Paul B :boozing:
Title: Re: How to separate long-connected exhaust pipes?
Post by: MattP on July 23, 2021, 03:51:37 PM
heat will allways work just a matter of how much. Matt
Title: Re: How to separate long-connected exhaust pipes?
Post by: Madtownguzzi on July 23, 2021, 06:14:11 PM
Alternate between hot and cold with CRC Freeze-Off super penetrant
https://www.autozone.com/greases-and-gear-oil/multi-purpose-anti-rust-lube/p/crc-freeze-off-super-penetrant/898352_0_0?cmpid=LIA:US:EN:AD:NL:1000000:GEN:71700000069889792&gclid=Cj0KCQjw0emHBhC1ARIsAL1QGNe-V1ajoQ0QRbzV-S8R7TlY242ssRV2VWc2bplBS00l3Jy4m8169ysaAmwyEALw_wcB&gclsrc=aw.ds
Title: Re: How to separate long-connected exhaust pipes?
Post by: 73 sport on July 23, 2021, 07:50:26 PM
    After disassembly and cleaning or installing new exhaust components, coat mating surfaces {sliding fits,flanges & gaskets} with Nickel Anti seize . Don't use copper antiseize, it can corrode stainless steel and doesn't have the high temp quality.
Title: Re: How to separate long-connected exhaust pipes?
Post by: moto on July 23, 2021, 08:34:23 PM
    After disassembly and cleaning or installing new exhaust components, coat mating surfaces {sliding fits,flanges & gaskets} with Nickel Anti seize . Don't use copper antiseize, it can corrode stainless steel and doesn't have the high temp quality.

Thanks. I'll be using chromed exhaust parts, not stainless. Is nickel best for that? What about molybdenum disulfide?
Title: Re: How to separate long-connected exhaust pipes?
Post by: Tom H on July 23, 2021, 11:34:59 PM
Permatex black silicone adhesive sealant also seems to work well.

Another use for anti sieze...HD specifies it for pivot points on the shifter and brakes pedals. Go figure?

Tom
Title: Re: How to separate long-connected exhaust pipes?
Post by: 73 sport on July 24, 2021, 08:55:45 AM
    Google "Anti-Seize". The companies, A.S.T. Industries; CRC Industries; Bostik, have detailed explanations of Where, When, Why to use grease, lubricants, anti-seize. My experience with nickel anti-seize goes back sixty years using it on aircraft and oceanographic instrumentation and machinery. It doesn't react with dissimilar metals under extreme heat or extended periods exposed to salt water
Title: Re: How to separate long-connected exhaust pipes?
Post by: John A on July 24, 2021, 10:12:28 AM
Wait, there’s more!  Nickel anti-sneeze color matches with the exhaust and aluminum
Title: Re: How to separate long-connected exhaust pipes?
Post by: bmc5733946 on July 24, 2021, 10:33:01 AM
When using the method I described it is the rapid water cooling that does the work.

Brian
Title: Re: How to separate long-connected exhaust pipes?
Post by: John A on July 24, 2021, 11:54:40 AM
When using the method I described it is the rapid water cooling that does the work.

Brian




Yep,
The rapid temp change can help break the bond that corrosion has made