tight exhaust nuts

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stuart
Cucciolo - the Lil Pup
Posts: 24
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tight exhaust nuts

Post by stuart »

hi all i have the spanner ,have the confidence,have had the rear cylinder nut loose. but the front one is the nut from hell :twisted: given it a spray with wd 40 and pulled the spanner as hard as i can and i am 18 stone . should i give it a few gentle taps with a hammer or hit the living daylights out of it any ideas out there
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Craig in France
Paso 750
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Tight nut

Post by Craig in France »

Hi Stuart

My best advice is, exercise patience. You don't want to get yourself in a situation where the lobes on the ring are broken ...

Thoughts:

1. Get some better penetrating oil - WD40 isn't that good. Give it time.

2 Try a bit of heat. The rings are brass, the heads aluminium so you may be able to get some different thermal expansion.

3. Try tightening the nut first.

4. Try increasing the leverage on the spanner by using a piece of pipe. But remember the rings are brass and aren't very strong.

HTH and good luck!

Ciao

Craig in UK
big phil
Mariana
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Post by big phil »

hello stuart.
i had the same problem with the rear cylinder on my 900ss and i ended up being fairly brutal with it.i did break a few fins off it but so long as you know where to get another nut from or you dont mind a few broken fins then it s ok.i shifted the special spanner around to different points and smacked it with a hammer after letting it soak in a really good penetrant for a few days.it was so tight that it warped the spanner but it came off eventually.hold it in postion with a rag around the pipe and belt it.just dont damage the thread in the head
theres a certain quality in quantity
stuart
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Post by stuart »

the only thing about the nut is a former owner had already broken quite a few fins but i have enough left to fill the spanner even if i move it around am more than willing to be very brutal its a case of :-D or maybe a case of :cry:
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Geoff
Parallel Twin
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Post by Geoff »

I ended up using a stilson (pipe wrench) as the PO had well mangled my front one. Held fast with carbon. Lots of penetrating oil, heat, and a correct wrench were tried to no avail. But the pipe wrench worked......
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Spub
Mach 3
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Post by Spub »

While working on my 900SS a couple of weeks ago I attempted to remove the exhaust. The rear jug's nut came off without a hitch, but the front jug's nutmust have been welded in place....no amount of torque (using the proper nut wrench) seemed to budge it. After a lot of WD 40, carb cleaner, chanting, a voo doo spell or two and coaxing from a shayman's incantation, it finally gave way....man, there was a ton of carbon that essentially acted as a red loctite (high temp version, of course)....I am just speculating, but perhaps the orientation of the front jug compared to the rear causes this build up....I was also surprised by the delicate appearance of the threads. They were much finer and shallower than threads I have seen on other bikes that had screw in exhaust nuts....I am also glad to see there are other at home mechanics out there who appreciate the subtle niceties of a pipe wrench, a tool which I feel has always been under-utilized, under-appreciated, and under $10 (chinese version) at most hardware stores.....
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stuart
Cucciolo - the Lil Pup
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Re: tight exhaust nuts

Post by stuart »

the latest episode of the stuck front cylinder is after round 6 the nut has won all the rounds now i have used a second spanner loads of the lobes are now missing now its going to be a lot more heat some more plusgas and a pipe wrench .
if all fails and the thread is damaged i have sourced an engineer to repair the thread
maybe i need a bit more patience though .and a bigger pipe wrench
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ColinS
Mariana
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Re: tight exhaust nuts

Post by ColinS »

If the bike is a runner then get it hot. The head will expand more than the nut and will loosen off to a degree. It's probably been tightened when hot which is one way to make sure they don't come loose in normal usage.

Regards

Colin
Colin Steer
Keswick
Zanetti
Cucciolo - the Lil Pup
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Re: tight exhaust nuts

Post by Zanetti »

Google "penetrating fluid comparison" a home brew 50/50 mix of ATF and acetone beat all the commercial available stuff.

Also did you try tightening it a bit to break the bond?
I have read of another owner who gave up and hacksawed the header pipe to get the head off then used a dremmel to gradually grind the pipe and nut away from the head.
also remember the bike only understands Italian so liberal use of phrases like si staccano stupido bastardo* might work

Good Luck

*google translated, I don't speak the language
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BevHevSteve
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Re: tight exhaust nuts

Post by BevHevSteve »

I like KROIL sprayed on liberally, over a few days, lots of heat, tighten if possible then loosen. If you get ANY movement either direction that's good, just be patient and keep spraying KROIL soaking and heating/cooling - again - over days and days.... Be patient
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Riv
Cucciolo - the Lil Pup
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Re: tight exhaust nuts

Post by Riv »

CRC sell a 'Freeze and release' product here in Oz, it works a treat. In your application heat the alloy (electric hot air gun is ideal) then spray this cold stuff on the nut. It has worked for me on some real pregnant dog fasteners, I recommend it highly.

Regards
'82 SS 900
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bobnorton
860 GT / GTS
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Re: tight exhaust nuts

Post by bobnorton »

Remove the silencer and the balance pipe first as they can load the pipe and help it jam, when leaning on the wrench also apply load to the pipe , always worked for me on stuck Norton rings.
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