OzVMX Forum

Clubroom => Bike Talk => Topic started by: evo550 on March 09, 2008, 06:28:19 pm

Title: Anyone got a bigger hammer?
Post by: evo550 on March 09, 2008, 06:28:19 pm
I have a problem getting a barell off. The piston seems to be seized into place through years of being in the elements without a sparkplug in place.
The crank still spins( I took the base nuts off and I can lift the barell), but the piston seems wedged in there.

I have tried all the standard soakings and heat to the cylinder and bashing, so far no good.
Any ideas?
Title: Re: Anyone got a bigger hammer?
Post by: oldfart on March 09, 2008, 06:57:42 pm
Block up all the ports with rags or similar and fill up the bore with brake fluid and let it soak it for a few days .     


Title: Re: Anyone got a bigger hammer?
Post by: Hoony on March 09, 2008, 07:03:47 pm
another option is to cut the rod in half with a cutting disc so you can get it on a press and press the piston out maybe.

assuming the crank will need a rod kit anyway due to the weather damage.
Title: Re: Anyone got a bigger hammer?
Post by: paul on March 09, 2008, 07:09:41 pm
turn  it up side down in the vise and melt the piston with the oxy  a  bit
Title: Re: Anyone got a bigger hammer?
Post by: evo550 on March 09, 2008, 07:47:44 pm
Brake fluid has gone in.
Hoony good idea but the piston is at about 15mm from TDC so I can't even get the cylinder off the bolts, if it was at BDC all would be good.
Paul, If brake fluid fails out comes the oxy.
Title: Re: Anyone got a bigger hammer?
Post by: jimson on March 09, 2008, 11:26:11 pm
Years ago I had the same problem undo the bolts on the barrel take the bike to the top of the biggest hill you can find lift the ass end of the bike and run like crazy then drop the back end down to the ground  you might have to do this once or twice but it should work its the sudden jolt that opens it up just be carefull you don't trip over the bike when you drop it also have a camera ready ::)  just in case.jimson
Title: Re: Anyone got a bigger hammer?
Post by: holeshot buddy on March 10, 2008, 08:47:43 pm
i got a kx500 engine off a guy his ex attacked it with an axe and poured sand and sea water
down plug hole  :o
was seized near tdc i soaked it in diesel for a week then got a big ::) hammer
suspended motor off ground and layed into it from the top >:(
like there was no tommorow
it worked took a bit though i only wanted it off to acces gearbox which was still ok ;D
Title: Re: Anyone got a bigger hammer?
Post by: All Things 414 on March 10, 2008, 08:58:14 pm
Apparantly Hoony's technique is straight out of the Honda manual.....
Title: Re: Anyone got a bigger hammer?
Post by: brent j on March 10, 2008, 10:34:27 pm
I made up a rig years ago to remove some cylinder from and old aircraft engine.

A plate bolted to the head studs with a threaded hole to accept a porta-power ram. We would build up some pressure, soak it in CRC or such and leave it over night. We used heat on a few but they all came off in the end. We were after the sleeves but usually did no or minimal damage to the other parts.

You could make something simillar by making a frame to bolt to the head studs and hold a car jack. Constant force on the piston with a bit of heat might get it to move.

Brent
Title: Re: Anyone got a bigger hammer?
Post by: GMC on March 10, 2008, 10:50:07 pm
I would try drilling some holes down through the top of the piston which should help relieve the pressure against the cylinder wall. The gudgeon pin will stop you breaking the crown off completely but if you get some large holes front & back you could then run a hacksaw blade through the skirt to also help relieve pressure, then try that big hammer again ;D
Use some good old duct tape to make a handle on the end of the hacksaw blade.
Title: Re: Anyone got a bigger hammer?
Post by: Tim754 on March 10, 2008, 11:16:11 pm
Don't try using 1200gms of Semtex plastic expl... it does not work...... And wastes a good detonator and KX80 gearbox,clutch ,head. barrel,frame, triple trees etc:(
Title: Re: Anyone got a bigger hammer?
Post by: Hoony on March 11, 2008, 05:23:45 pm
Apparantly Hoony's technique is straight out of the Honda manual.....

Nice one   :D 


Shit, i have no comeback ??? i'm losing it
Title: Re: Anyone got a bigger hammer?
Post by: Hoony on March 11, 2008, 05:26:03 pm
Don't try using 1200gms of Semtex plastic expl... it does not work...... And wastes a good detonator and KX80 gearbox,clutch ,head. barrel,frame, triple trees etc:(

Shit Tim, you really are Crazy (Glad i never swung for you  :D)
Title: Re: Anyone got a bigger hammer?
Post by: Tim754 on March 12, 2008, 07:34:28 pm
Oops Sorry Hoony incorrect fact stated, it was C4 not Semtex. Mate and partner in the "failed attempt to remove stuck barrel" has admonished me for that silly mistake. :-* And if i ever get the any of the 754s back on track, you can find a fool to hang on side and pilot them yourself on me no kidding  ;) Tim
Title: Re: Anyone got a bigger hammer?
Post by: Wombat on March 12, 2008, 09:41:07 pm

i got a kx500 engine off a guy his ex attacked it with an axe and poured sand and sea water
down plug hole  :o

Are you serious; she attacked it with an axe?! :o
Note to self: If bike becomes the Mistress, hide the axe...
Title: Re: Anyone got a bigger hammer?
Post by: holeshot buddy on March 12, 2008, 11:55:40 pm
yep she caught him rooting someone else and that bike was his pride and joy ::)
she hooked into it with an axe  8)
everything was hacked i got bugger all off it  :'(
mainly wanted gearbox that was still good she could not quite reach it ;D
it was an 85 kx500 not many around one less now :'(
Title: Re: Anyone got a bigger hammer?
Post by: mx250 on March 14, 2008, 01:06:38 pm
yep she caught him rooting someone else ....

Expensive nookie :o ::) ;D

He might consider himself lucky. Sounds like it could have been him if he stood still long enough :P.
Title: Re: Anyone got a bigger hammer?
Post by: Hoony on March 14, 2008, 02:04:01 pm
....................................And if i ever get the any of the 754s back on track, you can find a fool to hang on side and pilot them yourself on me no kidding  ;) Tim

this forum is full of Fools (me included) so no problem there!

How much Penetrene & CRC have you got Tim? It's been 20 years since i piloted the KTM540, so i am very bloody rusty.
Title: Re: Anyone got a bigger hammer?
Post by: Tim754 on March 14, 2008, 02:54:54 pm
C4 removes rust too.................. ;D You see the 754 for sale on eBay ,in sidecars above ;)