Stuck piston

Hi

I'm just trying to sort out an old Land Rover - it's got a 2 1/4 petrol fitted to it. It's been stood for 25 years in a garage but the number 3 pistons stuck. Got the head off and dropped the sump but best I've managed so far is to drive it down a bit.

It'd been left for months before hand with duck oil in to try and free it off but doesn't seem to have worked. There's no rust on the bore but it took a bit of belting to get it to go down. Now maybe I should have tried driving it up but there I was ever hopeful of it freeing off.

Haven't got the gear to take the engine out so any bright ideas for getting this moving short of drilling the crown and trashing it?

Thoughts I'd had where boiling water in the block and freezer spray from under the piston to give a bit more room or getting an air hammer and a blunt chisel bit and trying to drive it back up that way. Can't really get any welly on it from underneath and trying to jack it up just lifts the motor.

Cheers

Baz

Reply to
Barry Cade
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Before you took the head off did you try towing it and then dropping it into gear? id have thought this would have been easier?

also - hiring or borrowing an engine lift is probably less work than smashing the piston up and will be cleaner and less hassle.

Reply to
Tom Woods

Diesel is pretty good for unsticking piston rings and stuff try warming it up first so the DERV penetrates then leave for a couple of days. Place a short length of timber on top of the piston and encourage it to move with a BFO lump/sledge hammer > 4lb, then try from the other side you could even jack it up and just leave it over night. As far as I can see though the engine is going to have to come out at some point cos a pound to a penny the bore is going to be fecked and need honing if not a rebore Derek

Reply to
Derek

I've also heard good reports of long soaks in diesel doing wonders for stuck bits. Though I'd be tempted to give it several liberal applications of plusgas first spread over a few days. Any place that could possibly lead to the piston/bore/ring joints so top and bottom and gudgeon pin etc

Make sure your driver is driving square as well. So a something that is seated all round the piston crown and hit in the middle. Not a random bit of small timber just whacked.

Reply to
Dave Liquorice

Drive it back up by whacking one of the other pistons down? Once you get a bit of movement both ways it should start to free off. TonyB

Reply to
TonyB

I used to work as a diesel fitter, and we used to keep a tub of stuff for freeing up rusted solid items. The tub contained mainly diesel, but also included brake fluid, engine oil and hydraulic oil. Might be worth leaving the rod connected to the crank, that way you can use a big flat screw driver on the ring gear, you will get some serious mechanical advantage, and if you try working it up and down that way you will soon find if it is working free. Doing it this way shoul restul in no added damage to the piston / bore. It would also be worth getting some fine wet and dry and remove any corrosion from the bore first, that way once the piston breaks free it won't get stuck again on fresh rust. Once the piston dose come out, resist the temptation to try and free up the rings, leave it for a week or more to soak in diesel or what ever, this is because the rings will most likely be stuck in their grooves. Trying to work em free will most likely restul in a snapped ring.

Hope this helps. Simon

Reply to
Simon Cochran

Hi

Thanks for the ideas. Before I took the head/sump off it had had duck oil, a freeing off agent bit like plus gas, in the bores for quite a few months. Did take it out and tried towing it but just left black lines down the road in top with four wheel drive engaged. Unfortunately the clutch plate is stuck to the flywheel face, and wouldn't free off, so can't get speed up and drop the clutch.

I did try wolloping another piston to get it back up but it doesn't want to move. Also have taken out the radiator and removed the timing cover to get a better purchase with a large pair of stilsons on the crank starting handle dog but even with a large piece of pipe on a pair of 36" stilsons it doesn't move - though I don't want to strip the crank thread.

Bore seems clean where it's driven down so should be no reason why it can't come back up but yes I did use wet and dry with oil to make sure the bore was as clean as it could be.

Maybe that as the engine had been bored and new pistons fitted back in

1983 and it didn't do that many miles before being parked up it's not got the benefit of 40 plus years of wear.

Anyway thanks for the input and ideas.

Cheers

Baz

Reply to
Barry Cade

There is a "last resort" tactic, which probablu doesn't come under the heading of non damaging. It's also pretty dangerous, so I'm not advising it (I've just seen it done)! Stick a bit of timber up from underneath and try jacking it up - though that may well get the liner out as well, or the split the engine mountings......

Richard

Reply to
beamendsltd

beamendsltd uttered summat worrerz funny about:

I'd have thought driving it up is definately the way to go, it may be moving in to an area of unworn cylinder which is agrivating the situation.

Lee D

Reply to
Lee_D

I personaly think lots of heat , close to piston melting would stand a good chance (oxyaccetylene cutting torch used carefully)

-- Jon

Reply to
jOn

jOn wrote: (oxyaccetylene cutting torch used carefully)

non-sequitur or what ? ;-) Steve

Reply to
Steve Taylor

Dunno my pal Chris used to 'carefully' cut 18inch RSJ's with an oxy cutter personally I wouldn't get within 3 feet of an engine with one if I ever wanted it to do simple stuff like 'turn' ever again. I have happy memories of my late father heating voided bush brackets on MK III Cortina's before 'carefully' drifting out the bushes with a 6lb lump hammer used at full swing they invariably 'gently, bounced off the back wall of the service bay. Derek

remembering Gerald Thorniley 'MOT' Watts

Reply to
Derek

Before you go to that extreme, I'd dissolve the piston away using caustic soda. (sodium hydroxide) It doesn't affect the steel or iron. Though I suspect that the problem would be when the first pin prick hole is 'through' you loose the liquid down it.

AWEM

Reply to
Andrew Mawson

Cunning. Pack behind the piston with plasticine...

Steve

Reply to
Steve Taylor

Easy to heat things up with a cutting torch, just don't press the trigger.

-- Jon

Reply to
jOn

I thought that but then you are running acetylene rich ( and a bit smoky IIRC) wouldn't a welding torch would be more controllable in that situation? I would be shying away from it myself but then I dont use gas air kit and my brother was more than a little adept at getting blow backs thank god for flame arrestors! Derek

Reply to
Derek

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