Marine engine overhaul / condition testing question

Hi,
I could ask this on a yottie forum but I know several of the posters here have businesses in the engine domain so I thought I'd try here
first :
I have a chance to buy a 1500cc marine diesel engine (Thorbury or something, but I believe it's a marinised Leyland engine). I've been told it dates from the late '70s but has never been run. From the pix I've seen that looks surprisingly likely but I just wondered what it's condition is likely to be like after so long ?
Aiui, it's been mounted in the bottom of a boat that's never been floated so has been kept out of the weather but has been exposed to temperature variations for at least the last 20 years. Will the rings have rusted to the bores do you think ?
What would you do to check its condition without taking it apart ? I guess trying to gently turn it over by hand would be a first step, but is there anything else you'd do ?
How much would it be likely to cost to have such a beast reconditioned after all these years ?
Any suggestions or advice gratefully received,
David
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Any engine thats been stood without proper provision for storage is likely to be seized IME. A saving grace in this case might be if its never been run then it *might* have been built with 'preserving lubes' so that it could be stood whilst the boat was built. These are likely to be gummy and varnish like now, but thats better than the alternative of rusted bores and seized rings. The Valve train might also be stuck, as at some point in the cycle there are one or more valves off the seats, and these have been sat that way for some time. Id inspect it first, noting how much surface rust and its general condition. If you can remove the manifolds and injectors then have a peer in with a good torch. If the insides of the ports are badly rusted then the bores are likely to be the same. Then try turning it over (somewhat gently) with something like a socket and breaker bar on the end of the crank, where the flywheel attaches (assuming this is possible) Its likely that you wont be able to turn it over, in which case if you can make a second visit some time (week or so) later then try pouring some diesel into the bores and letting it sit, then try the same again. If you cant then you have to judge if the rest of the engine is likely to be worth the hassle of a full strip and rebuild, including honing/reboring for rusted bores, valve springs and bearings. I suspect the crank journals *should* be ok, as the normal build practice is to ensure the shells are well oiled before assembly, and the journals are not really exposed once assembled. hth Dave
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wrote:

Any engine thats been stood without proper provision for storage is likely to be seized IME. A saving grace in this case might be if its never been run then it *might* have been built with 'preserving lubes' so that it could be stood whilst the boat was built. These are likely to be gummy and varnish like now, but thats better than the alternative of rusted bores and seized rings. The Valve train might also be stuck, as at some point in the cycle there are one or more valves off the seats, and these have been sat that way for some time. Id inspect it first, noting how much surface rust and its general condition. If you can remove the manifolds and injectors then have a peer in with a good torch. If the insides of the ports are badly rusted then the bores are likely to be the same. Then try turning it over (somewhat gently) with something like a socket and breaker bar on the end of the crank, where the flywheel attaches (assuming this is possible) Its likely that you wont be able to turn it over, in which case if you can make a second visit some time (week or so) later then try pouring some diesel into the bores and letting it sit, then try the same again. If you cant then you have to judge if the rest of the engine is likely to be worth the hassle of a full strip and rebuild, including honing/reboring for rusted bores, valve springs and bearings. I suspect the crank journals *should* be ok, as the normal build practice is to ensure the shells are well oiled before assembly, and the journals are not really exposed once assembled. hth Dave
Quite a few Leyland marine diesel engines were sold here on the west coast of canada. Several friends had them, some in commercial fishing boats. They had a great reputation. It's probably worth doing a valve grind. no doubt the pistons/rings will be stuck in the bores. sometimes all they need is a good bif wif an 'ammer, cushioned by a length of wood resting on the piston. as another poster mentioned, a shot of diesel oil in each bore, and a bit of time will often free them up.
Steve R.
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Thornycroft, perhaps? They marinised the BMC 1500/1800 for a number of years, later versions of the engine being imported from Pakistan and Turkey. These engines are still common in UK inland waterway boats, specialist firms are AMC in Preston and Calcutt Boats in the South midlands if you need parts.
Dave's advice makes sense, I'd budget for at least taking the head off and cleaning up valves & seats. You might just be lucky and get away with a quick manual cleanup of the bores with the head off.
Tim
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I wouldn't expect the inside of the engine to be rusty unless it has been stored in a very damp environment. I bought a stationary engine which had sat in a barn for a decade or two with the spark plug removed, and the bore still wasn't rusty. If it turns over and is genuinely unused, you're probably fine. But like Tim says, you'll want to open the engine and check it over before running. Change the oil, look for dried up lubricants and replace the gaskets if they're starting to deteriorate.
Best wishes,
Chris
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