Piston Seized in Barrel

[shaunlacy]

Morning all, I have a TS125 with the piston seized in the barrel, its near the bottom, so a lot of the piston is where the inlet/exhaust ports are so I cant get penetrating fluid to stay in. I have given it a good bashing with a steel rod but still no movement.

Anyone any good ideas???

Shaun

[Puffs]

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[shaunlacy]

Hi Puffs, thanx for the reply. I wasn't bashing too hard as I was worried about damaging con rod! Two of the studs came out as the nuts were solid, so I might try to get the other two out and see if I can get some purchase on it that way. Not too worried about damaging piston as a new piston set is only £46.00 but I am worried about damaging con rod/small end!

Thanks

[dirtsurfer]

Morning all, I have a TS125 with the piston seized in the barrel, its near the bottom, so a lot of the piston is where the inlet/exhaust ports are so I cant get penetrating fluid to stay in. I have given it a good bashing with a steel rod but still no movement.

Anyone any good ideas???

Shaun

It's amazing (to me ) how a seized piston can be so tight!. I also resorted; against my better judgement; to bashing with an axle from a wheelbarrow. When I finally got it out, the only marks in the bore were from water damage and where my hammering contacted the bore No indications of the seizure in the bore. So I second Puffs recommendation for the reasons he mentions and to anyone else who may be reading, try and use wood. * The other thing is take notice of your piston size stamped on the crown before you obscure it with hammer blows.

Optimize your work conditions.: if the engine is in the bike, take it out so you have plenty of room.
Can you rotate the crank so as to raise the cylinder out of the crankcases then jamb some wood under the cylinder tho stop it slipping back when you apply pressure

If you can block off your inlet holes with greased rags stuffed with cooking foil you may be able to soak some WD 40 or my preferred diesel into the contact area.
If you can remove all the cylinder studs, you may be able to twist the cylinder. As well as little end and conrod,you have to be careful to protect your big end from debris as you may snap a ring; If you're not planning on splitting the cases anyway .
These are all desperate options and ran through my mind when I was faced with a similar problem.

Good luck

[Blurredman]

I had a very similar problem with one of my MZ's when I got it.
13 years off the road, not only was the piston well and truely seized, but it appears it was seized due to water ingress. Luckily the piston was half way up the barrel and covering the ports, otherwise the crank would be toast.

However.. I had to hammer the crap out of it. The piston was 3rd oversized anyway and upon getting the two seperated, was pretty well scored. The barrel also had a lot of corrosion in the form of water concentration utop the piston that only a 1mm re-bore would remove, esspecially near the frontal wall.

New piston and re-bore was required.. At least for me, anyway..

[shaunlacy]

Well, I managed to get all of the studs out, but it still isn't for budging, worried about twisting too much, don't want to bugger big/small end bearings!

Will a gas torch on the barrel help, or will the piston heart up quicker?

[Puffs]

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[shaunlacy]

Cheers puffs: Difficult to soak it cos of inlet/exhaust manifold, but I like the idea of a bolt/screw to force piston down. I think I can make something to that with.

Be back with the results soon . . . . .

[shaunlacy]

got the scissor jack off my Landrover and created a screw - still no movement, blanked inside the barrel with a wooden insert so as not to damage barrel & piston!!!! AAAAAAgh!!!!

[shaunlacy]

Broke Jack! other half furious lol! oh well, next idea . . . . .

[dirtsurfer]

I would have thought something else would give before your jack broke. Whip the engine out of the frame and start pounding. Tell her you love her

[DAVID THOMPSON]

bolt it down in a milling machine and use a cutter to whittle it out of there
just make sure you miss the con rod small end area

[Puffs]

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[shaunlacy]

Hi, definitely not TDC, it dropped about 3/4 of an inch onto blocks, If i thought I could get e replacement barrel I'd cut it off but they look rare as rocking horse .....
That jack lifts my Landrover, so at least two tons of force applied before it buckled . . . scratches head . . .

On the plus side just been out for a good long ride on another bike so am chilled now, will look at it later in the week!

[dirtsurfer]

. .

On the plus side just been out for a good long ride on another bike so am chilled now, will look at it later in the week!

A good ride helps to clear the mind

Can you see where the bore is scored? If so you could drill some holes in the crown of the piston close to the side. Then inserting a narrow cold chisel or use a dremel to work away at the piston and rings in the bound area