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Discussion Starter #1
I'm rebuilding a 71 T100R that's been stored for over 20 years. Right now I'm trying to unstick the pistons. I'm soaking in PB Blaster, using occasional heat, and waiting.

Any advice?

Here are some pics. They're pretty big, so if you're on dialup, it will take some time.

http://bullfire.net/Triumph/Triumph.html
 

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Could also be the crankshaft seized. Once soaked for a few days (try some diesel fuel as a a unsticking agent), try pulling the cylinders up over the pistons, rather than rotating the crank. If the cylinders and pistons come up, the crank should rotate, and it's definitely the pistons stuck in the bores. If the cylinders still won't come up with pistons attached it's likely to be a combo of both the pistons stuck in the bores, and the crank seized.
 

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i've heard this method, but never tried it personally....

1. make a flat blanking plate, using head gasket as a template.
2. install 2 zurk fittings in plate, over the bores.
3. fit head gasket, plate, and bolt to head.
(use either long original head bolts with a s-load of washers, or find proper shorter bolts.)
4. start pumping bores full of grease.

with luck, once bores are filled, you will be using hydralic pressure to either/both push the pistons down the bores, or the barrels up off the pistons.

good luck, -j
 

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Discussion Starter #4 (Edited)
OzBloke--

Thanks for the advice. I should have mentioned that I've unbolted the cylinders, and can raise them up by turning the crank. It turns hard, but turns. With the cylinders fixed, I can't turn the crank.

NHOJ--

Hope it doesn't come to that, but I'll try it if I have to. Thanks.

Think I'll give it some more time.
 

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raise the cylinders , block under them with wood , not on the fins , and give them each a rap (the pistons) using a soft piece of wood and a hammer . the cylinders are all you're going to salvage . if its that rusted you'll have to bore them . not that the pistons could be saved anyway .
 

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Pour coke onto the pistons and let it sit overnight. The pistons as mentioned are scrap. If the cylinders aren't past the bore limit you will salvage them. Good luck.
 

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Discussion Starter #7
Thanks, everyone. Cylinders still have original bore, so I guess I'll be looking at an overbore and some new pistons.
 

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woody's suggestion is good..
if it dosen't do the job here is another approach using the headbolts, as follows..
1. get 2 pieces of angle iron that will span fore/aft head bolt holes.
2. drill angle to accept head bolts.
3. get a stout chunk of board that will fit sideways under angle, over both bores.
4. wind head bolts halfway down their thread length.
5. measure distance from piston top to bottom of board, while holding board up, under angle, under bolt heads.
6. use measurement to make 2 stout blocks of same size.

so now set blocks in bores, put board over across both boars, over blocks. put the two angle iron straps across board. insert head bolts.
tighten as if tourqueing the head down.
with a bit of luck you are now pressing squarely and evenly, forcing the pistons down the boars.
make sure you use at least half the thread length on headbolts as to not risk any stripping of threads. -j
 

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If the engine is having a hard time turning, with the cylinders un-bolted and able to rise and fall freely, take a look at your primary chain - it's probably rusted up and keeping the engine from rotating easily.

If not, STOP WHAT YOU ARE DOING! Your main bearings (bad) and/or your rod bearings (worse) are sticking and will only do further damage.

Not much way around pouring PB Blaster / WD40 / whatever in there, then smacking the pistons loose.
 
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