Apologies for the lack of updates but I've been busy removing valves, cleaning up the head and more recently, making a liner extractor tool and attempting to remove the liners.
I'm not quite sure where to begin because there is bad news to report, or at least . . . potentially bad news.
I will start with the liner extraction.
So, for those of us unwilling to splash out £160 on Triumph's special tool, it seems there are two methods that receive popular support
1. Wrap duct tape around the inside of the liner, hand crank the engine and use the force of the piston to simply drive out the liner and . . . .
2. Make a clone of the Triumph tool using a 3"/75mm steel drain plug tester
I opted for the latter and I'm so glad I did. . . . . Some folks report pushing out the liners as a simple and straightforward affair and I have come to realise this depends totally upon the security of the silicone seal at the base of the liner - mine were tight, very tight indeed. I can categorically state that if you attempted method 1 on my engine, there is no doubt whatsoever in my mind that you would damage the pistons and/or rings. The amount of force required to lift the liners on my engine was massive and of course, the piston would attempt to squeeze past the duct tape and all the force would be taken by the first ring and land.
I purchased the plug, a short length of 12mm threaded rod and glued it into the plug. A washer and a couple of 12mm nuts completed the parts list - total cost from eBay - just under £14.00. I then set about making a wooden "bridge" which I backed with some sheet rubber to protect the gasket face of the engine block.
Sadly, my tool didn't perform as expected and despite doing up the plug as tight as I could, operating the draw nut merely resulted in the plug sliding up inside the liner. Don't get me wrong . . . it was resisting admirably and the amount of force required to move the thing was significant but at the end of the day, it was the plug which moved and not the liner.
I guess I tried about 20 times in total before retiring to sleep on it. . . .
I made another attempt today except this time, I wrapped about two layers of duct tape around the top of the liner and a strip of bicycle inner tube, held in place with double sided tape - I figured that short of reverting to semtex, this had to work!!?? I tightened the draw very slowly and kept the whole thing under significant tension in the expectation the silicone seal would be getting constantly stretched and sooner or later would start to let go and peel free - This seems to be pretty much what happened. After about 5-10 minutes of slowly turning the nut, each liner suddenly let go and it was "job done".
I'm away now for a few days and didn't have time to remove the liners and pistons from the engine but that will be my next job on my return, however, I'm feeling rather despondent about where this whole exercise is leading and I will post and explain separately below.
I was nervous of scratching the bores with the tool. It has a minimum useable diameter of 75mm and goes up to 83mm or thereabouts. To prevent any mishaps, I tightened the wingnut by hand until the rubber was compressed and the tool was a smooth, sliding interference fit in the bore, having previously wiped it down with brake cleaner - this meant there was no chance of metal to metal contact.
The two 12mm nuts are then locked together at the top of the threaded rod and . . . .

. . . . . . this allows the rod to be held with a spanner whilst the wingnut is turned and the tool tightened in the bore as much as possible. Having done that, the nuts are removed, the bridge placed over the top, before adding a washer and nut and slowly tightening in an attempt to draw up the liner.

20 attempts and some 2-3 hours later and I had made no progress whatsoever and all I had achieved was . . . . . .

To draw the plug up inside the liner and for the liner to remain steadfastly glued to the block

After sleeping on it overnight - this was my next attempt. A couple of wraps of duct tape, followed by . . . .

A length of inner tube, held in place with double sided tape and then the tool inserted below this added restriction. I suspect that even this method won't work if you merely tighten the spanner rapidly. The key is to apply a constant steady force by slow turning of the spanner . . after about 5-10 minutes in each case, the liner suddenly released.

This picture shows the tool in use but as always, I overlooked something . . . . Having released the central liner and raised it a couple of millimetres, it then meant my tool wouldn't sit square on the head - hence the randomly inserted pieces of thin plywood to raise the tool above the liner. Duh . . bit of an oversight but hardly a problem - I could have bashed the thing back in with a rubber mallet
