anyone know how to separate a stubborn exhaust?

[CrankyGypsy]

there are ten bolts attaching the large "collector" to the manifold. i have eight of them completely out (#9 and #10 in diagram). one that the head snapped off and another that seems to be fully unscrewed, but is still stuck in the collector. i also removed the four bolts that mount the exhaust to the injector side and the bolt that attaches the collector to the case (#2 in diagram), so as to remove it as an assembly. update: i recently learned i could have just loosened the large clamp on the rubber elbow to expose another clamp that secures the collector and elbow assembly to the large pipe rather than removing the four bolts below the injector that secure the pipe.

i can't seem to get any separation whatsoever from the manifold or the gasket. even hitting it with a hammer feels like it is still bolted on solid. i've tried heating the parts a few times with a torch, but no luck.
anyone have any experience here?

(success at post #14)

 

[Speedling]

Well, make sure that the one with the head broken off isn't flared out and is catching stuff so it can't come out.
Do you have the engine out of the boat or no?
Why are you taking it apart again?
@buckbuck is the only one I know that has taken any of this stuff apart.

 

[CrankyGypsy]

engine is out of the boat.
i have a leak(s) behind the manifold ...possible tiny case crack. need to get it apart to figure out my repair options.

 

[Speedling]

I haven't had it apart and am driving while writing this but are there alignment pins where you are trying to separate? Are you able to remove it from the head?
Worst case you remove the head

 

[CrankyGypsy]

can't remove the manifold without removing the collector (bolts are blocked).
yes, there are pins on both side of the manifold.
i have to separate the exhaust at some point since there is a broken bolt.

worst case will be cutting somewhere near the manifold and collector gasket ...then replacing it all. as big of a pain as this has become, i'm actually considering trying to pull the exhaust on the other motor just so i can replace the loctite with anti-seize, hopefully preventing this with any future maintenance.

 

[Cobra Jet Steering LLC]

Do you know how to weld ? I usually weld a nut to the broken stud, then let it cool, using a wrench I turn the welded bolt side to side if it starts to wiggle I get it positioned where gravity will work with me, I heat the surrounding metal with an acetylene torch, then place 90 weight gear lube so it can work its way down inside the collar and free up the bolt. Gear lube won't evaporate from the heat. After it cools try to wiggle it again , you may need to do it several times but it usually works.

 

[Speedling]

Those pins can be super stubborn.
At the risk of breaking something you can try and hammer a wedge where the gasket is to force it apart. Do this from both sides to lessen the likelihood of cracking the aluminum.
Perhaps a pipe band saw, like electritions may use, could be used to cut through gasket, pins, and bolts.

You are getting into dangerous territory and have to be prepared for something to break

 

[4x15mph]

I know my LS2000 had the dowel pins and by the look of your picture, you may also have these. I had tabs on the 2 sections that I needed to separate that were there specifically to pry off the exhaust ring. Surround the area with PB plaster regardless of whatever else you try.

I used blue loctite instead of red (listed in manual) when I put mine back together. It shouldn't be a problem to loosen and it doesn't require heat like the red usually does.

 

[Speedling]

I knew the 2 smokes had em (incredibly easy to work on btw) but didn't care to dive into the engine bay to see if the new ones do.

 

[CrankyGypsy]

thanks guys.
i'm getting aggressive with it: more acetylene and bigger hammers. PB Blasting/Soaking everything. i'm finally seeing the parts start to separate. i'm pretty sure that the snapped bolt (outside aft corner) is seized inside the length of its recess because this is where it's barely moving. if it doesn't free up, i'm gonna try using a cutting disc to cut through the wall of the collector and through the bolt. that might be weldable - if not, i'll have to find a used one.

still not having any luck on budging the seized bolt on the outer aft manifold.

 

[SCSTWG]

I think you are on the right course. Lubricate - then heat, rinse and repeat until you get it. Many moons ago I owned a business a ATV business and dealt with this scenario regularly. Some are more stubborn than others and it sounds like you have a tough one. Cobra-jet has a good suggestion of welding a nut on as well. The last thing I would add is to get as much leverage as possible by extending the length of your breaker bar or whatever tool you are using to break the bolt/nut free. Good luck.

 

[Speedling]

The whole assembly is cast aluminum, so it may be harder than you think to weld.

 

[CrankyGypsy]

the collector is off! didn't have to cut into the aluminum.
will post the pics once i sort and resize them.

i'll attack the other stubborn manifold bolt tomorrow.

 

[CrankyGypsy]

i had intended to try and sneak the whole assembly out with the flywheel/magneto cover still attached. but with the bolt head snapped off, there was no way to tilt the collector around the exhaust mounting bracket (#3 in OP diagram). i was getting a sliver of movement on the other three corners, so the shaft of the bolt was corroded and binding it all up:


being on the outside, i was able to safely get a lot of heat on it. i sprayed it PB Blaster then hit the tap point with a brass hammer and the rest with a dead blow several times. there isn't much to work with as far as separation goes considering how large the contact surface is. there is one tiny ledge to place a chunk of wood and whack it with a sledge:


after a while, i finally got it wide enough to get a good amount of PB Blaster in there. a few more rounds of tapping and i started to get decent movement:


there's no way to pull the exhaust as one assembly when there's 2 inches of bolt keeping you from sliding it out. i got it down pretty far before i figured it was going to start stressing all the other connections in the assembly:


got the grinder with a cutting disc, cut the bolt, and wiggled the entire thing out the front of the engine:


update: recently found you can loosen the hose clamp on the rubber elbow to expose an inner clamp that loosens a joint between the elbow and the big exhaust pipe. this should allow removal of the collector and elbow without pulling the magneto cover (to remove the bracket that sits behind the cover) or the airbox (to remove the bolts that hold the large pipe on).

it's an exhaust collector, but it is also appears to be a sand collector. i tipped it up and sand came tumbling out of the collector.
i'm confused here:


i'm probably going to re-install using anti-seize (or maybe blue loctite as 4x15mph stated). every single aftermarket exhaust that goes on a sportbike comes with anti-seize, so i'm comfortable also using it here.

 

[fairpilot]

I am curious to see manifold where it bolts to the head. That is where my issue was. Great job

 

[4x15mph]

Great job and lots of useful info for others that have to tackle similar jobs. I am not surprised about the sand since you should see what came out of my exhaust.

I am waiting on a new gasket for my carburetor cover since when I put the cover back on the other week, I did not use loctite and every single hex bolt was loose after the maiden voyage, test ride.... I think loc tite has some purpose in cases where there is heavy vibration. On my LS2000 that is anything that is connected to the engine including the exhaust. Again, I will never use Red loctite even though that is what holds up to heat and our manual calls for it in many cases. Time will tell how blue loctite works for me.

Glad you are moving along with the project.

 

[CrankyGypsy]

ok, blue Loctite on the threads and anti-seize on the bolt shaft.

 

[Cobra Jet Steering LLC]

Glad you were able to get it off without damaging it, you will also need to surface the parts to insure they mate up perfectly, I have a machine for that . I designed it many years ago , however a piece of heavy glass with 80 grit sand paper glued to it, bolted to a table or work bench to hold it in place and slide the surfaces across the sand paper until the entire surface shows a cut, if there is a low spot it will be dark and visible.
Do this to both sides of a part you are putting together. once your arms get tired you will understand why I made a machine to do it.
I always coated the bolt with bees wax where it made contact with cast aluminum. However never seize is probably just as good if not better.
The surfacing is actually very important , just one small low spot can compromise the seal and allow it to blow out again.

 

[CrankyGypsy]

unfortunately, i knew going in that my gasket wasn't the cause of my leak issue. but i definitely think there is some gasket issues going on.

i took @Cobra Jet Steering LLC recommendation and put some threads on the cut off bolt with a die, then welded a nut on. it came out with nearly zero resistance, so the blame for it being stuck was the shaft, not the loctite.



so i'm believing the red (or white) loctite is not to blame anymore. the problem seems to be the corrosion on the bolt shaft, specifically just shy of the mating surface. on some of the bolts, they were very hard to turn out. but once i cleared the threads from the bases, they would continue to spin in place ...and very tightly like they were still being held up by the loctite. i had to use a punch and hit them hard to bang a few out. i haven't even tackled the ones that are really stuck in the manifold, yet.

now i'm not sure exactly what the cause of this is.
maybe the threads are gumming up on the corrosion inside the bolt shaft recess, yet the threads can't bite the soft corrosion thus unable to worm its way out? once it runs out of tapped thread in the base, it basically jams.

there are crystals formed in the head exhaust ports and manifold, so water is getting in somehow. i had a cooling line blow a while back and inject gulf water into the airbox which put water in my oil. MAYBE this is from that, though i would think it would have burned off by now? just a guess, but it seems to be too much to blame this.
if the manifold is leaking water, it is staying on the exhaust side of the valves (looking down from the injector ports, it looks really clean for its age). if this is the problem, my guess is the 10-year old gasket isn't as tight as it should/used to be. it's tight enough to keep from leaking to the outside (or it leaks so little that it evaporates), but it must be seeping between the exhaust and water jackets ... there's a lot of odd build up that leads me in this direction.


yup, those are two hairline cracks in the case below port #3. awesome. going to take it all up to my local bad-ass welder to see what he thinks. and i'll probably be replacing that gnarly starter.

@fairpilot :

discoloration is likely from the PB Blaster and heat

i also pulled the engine anode (below port #4) - wasn't terrible looking but it did smell like raw fish and shrimp. i'll see about dropping that into my Sulfamic Acid to clean it up.

 

[Cobra Jet Steering LLC]

The gaskets probably leaked, resurface everything like I said earlier.
To pull the bolts out, weld a large nut vertically or chain link to the top of the bolts to make a loop, then use a small slide hammer with a hooked end to snatch the bolts out. if you don't have a slide hammer use a big pair of vice grips and hit the vice grip upward with a small hammer. Corrosion is probably built up in the bolt holes.