Stuart Turner P55

Hi all, it`s me again, the pest. I have a S-T P55 which has had water sitting in it for a number of years. Not one for shirking a challenge I have started to restore it. I thought it was worth restoring as I know the boat it was installed in, it belonged to my place of work fishing group. It has taken me over a week of teasing and prying to get the head off !!! The next part, the barrels, is proving to be a little more of a challenge. As it has had water inside, I am guessing that the bores are rusted below the pistons. I have managed to move it about an inch, but one of the pistons has imploded !!! Anyone any ideas on how to remove it the rest of the way without causing too much damage ????

Cheers, MartinH

Reply to
martin hirst
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Martin, I'm ignorant of the makeup of the ST. Is the imploded piston made of cast iron or Al?

Regards, Arthur G

Reply to
Arthur G

S'pose it's too light to use as a boat anchor ;-)

Seriously though, if the barrel is sufficiently corroded to destroy the piston on the way out, there seems little hope of salvaging either so you may as well chip the pistons out from the top with a cold chisel. I wouldn't hold out much hope for the bottom end if the top is that bad.

Parts should be available Fairways Marine at a price.

Reply to
Nick H

I don't think ally pistons arrived until P66, though they may of course have found their way into the earlier engine as replacements, B & S are the same.

Reply to
Nick H

We have 6 or 7 P55 engines in various stages of repair, all came down from Bonnie Scotland for No2 son to play with.

Pistons are cast iron and weld themselves to the bores very well, especially after long immersion in sea water!

Peter

-- Peter A Forbes Prepair Ltd, Luton, UK snipped-for-privacy@easynet.co.uk

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Reply to
Prepair Ltd

Does electrolysis achieve anything ? It's a slow process, because you have to stop every few hours and pressure-wash out the black dust, but it can achieve pretty good results in unsticking cast iron.

Reply to
Andy Dingley

Whereabouts in Scotland? I well remember the open motorboats which were for hire off Dunoon beach in the 60s, which had ST engines in them..................

Brian L Dominic

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Reply to
Brian Dominic me

Could we have: "put down their glass of wine, sat back and said:" :-))

Some came from Fife and the rest from Perth, but they could have come from anywhere really.

Peter

-- Peter & Rita Forbes Email Address: snipped-for-privacy@easynet.co.uk Web Pages for Engine Preservation:

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Reply to
Peter A Forbes

Done - it was due for a change, anyway!

Thanks - I wonder if any of our "members" from north of the Border know if they've survived??

Brian L Dominic

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Reply to
Brian Dominic me

Some years ago , I acquired a S-T 4hp with a seized piston. I got an old spark plug and broke the porcelain insulator out of it, welded a short pipe in and fitted a 1/8 in grease nipple. Screwed this assembly into the plug hole The piston was luckily near the top of its stroke, so application of a high pressure "Wanner" grease gun (claimed 8000psi) eventually moved the piston down the bore. The beauty of this method is the steady application of a large force over the whole of the top of the piston. I still haven't found a use for this little engine :-( Robert.

Reply to
Bob Holmes

I've got a couple of ST P55's, two in very sound, working condition complete with gearboxes and another in many pieces, sans block as it is very badly rusted - attacked, more like - and cracked, not from frost, I suspect, but by the wedging action of the sea water corrosion. I tried all sorts, including electrolysis, to get rid of the rust, but to no avail. I suspect that the salt has actually made its way into the structure of the iron and it leeches water out of the air everytime you wash it down and it dries.

Never one to give up easily, I think it is only good for scrap now. My honest advice is to do thou likewise, Martin, life is too short and pistons are expensive, it would certainly be cheaper and easier to get a different one (definitely under £150) and carefully conserve the one you have in old sump oil, awaiting the time in (say) fifty years when some future Son of Iron discovers it!

Regards,

Kim Siddorn

Reply to
Kim Siddorn

This might be of interest:-

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Reply to
Nick H

Interesting reading, Nick, if a little horrifying.

I've never been particularly excited by marine engines, and it seems I'm lucky!

Regards, Arthur G

Reply to
Arthur G

Thanks all, once again for some excellent advice. I am not going to give up on it just yet !!! Thanks for that link Nick, very interesting. Have managed to get it moving again on the studs. It seems to be a combination of both corroded studs and possibly the bores rusted. If it breaks it breaks, so I suppose theres no harm in trying. Will let you know how I get on, with some pics hopefully.

Cheers all, Martin

Reply to
martin hirst

Good luck, Martin. Rereading my previous post it seemed a bit condescending. That wasn't my intention, I will follow your progress with interest.

Regards, Arthur G

Reply to
Arthur Griffin & Jeni Stanton

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