thornycroft engine

[willtaylor]

I bought a Moody 333 with a Thornycroft 35 hp. It was going well enough. The surveyor pointed out that it was beginning to burn a little oil, but thought it quite serviceable. However, there were a number of relatively minor problems, mostly due to neglect by the unwell previous owner. Among them was the fact that the aft crankshaft oil seal was leaking. It seemed sensible to remove the engine for a thorough service, clean, and repaint. We could then easily clean out the engine compartment and modify exhaust etc.

I have received a bit of critical comment along the lines of ' It's only a Morris Marina engine ....... not really worth spending a lot on ......' that sort of stuff.

I thought it was a 1.5 litre BMC taxi engine orginally, and none the worse for that.
I have no problem with relatively unsophisticated machines so long as they work.
It seems to me that a 30-35 hp modern marine engine would cost a good deal more than a pretty big overhaul of a 20 year old BMC diesel.

The problem is, what would I have then? Is it likely to be reliable in itself for a number of years? I reckon most faults with marine engines come from ancillaries like water pumps, fuel and cooling systems. It's a sailing boat, but the big old lump under the centre cockpit is useful to get on and off moorings and would get us home ( I hope) or into harbour against wind and tide when needed.

I used it quite happily from the end of September until three weeks ago.

I shall welcome observations, opinions, advice - helpful thoughts and sympathy.

Regards,

Will Taylor

 

[stubate]

if you are a competent mechanic, go for it, phone ASAP-Supplies 01502 716993 for their catalogue and get in touch with a local workshop that does regrinds and rebores.
its lot cheaper to rebuild IF YOU KNOW WHAT YOU ARE DOING but if you dont and have to pay someone to do it for you then it can be an expensive option. you have to have the knowledge to be able to look at the bits and decide whether they are repairable or not.
if i remember rightly the bores are integral with the block and you would have to rebore, is it raw water cooling? if so is the block shagged ( a highly technical term used to describe a piece of terminally rusting metal) if not are the waterways clear? does the crank need a regrind? is the oil pump within specs? are the cam followers worn out/ is the cam shaft OK? is the cam chain worn and about to dive thru the timing case?
can your local diesel pump shop recon the injectors and injector pump or will you have to buy new? (ouch)
gear box ???
easy for an old time served fitter like me but do you have the skills?
these are all the questions you have to ask
s

 

[mtb]

Lovely engines these the valve stem seals gone have they or is it the actual stems.
Keep it and rely on it but remember they are difficult to bleed through when you put a new diesel filter on.
Some times susceptible to burning valves and even the odd head gasket .
They always seep a little oil if not from the main seal then from the side covers.
Actually I have a brand new set of plus 20"" pistons with rings that I will be selling oh and a starter ring gear !!.
Cheers
Mick


http://homepage.ntlworld.com/boats
I need a couple of oak tree's .. for me trawler

 

[squidge]

How bad is the smoke?Yes an overhall is in order but it may only need the head off and new valve seals?If no nocking noises and she starts and runs fine do you want the expence of a new lump with all the new problems that go with it.alignment,exhaust ect take a look at WWW.moodyowners.org The tech library is usefull ,Mick Parsons has just replaced his thornycroft in his 33 mk1.
Better the devil you know i say.your choice.Best of luck.

 

[Jcorstorphine]

Keep the engine, by the way it is not a diesel version of the Marina 1.3 that was a blown Morris Minor engine. The 1.5 is a diesel version of the old Morris Oxford/ Austin cambridge and also used in the J4 Post Office Vans. The engine will run forever with resoanble care. Spares can be obtained from ASAP and AMC up in Preston. A friend has just bought a fresh water pump from AMC without any problems. Your comment that it is now an old engine is only valid if the engine was direct sea water cooled and the jacket was corroded. I would give an example that it would be doubtfull if it was worth rebuilding an old Volvo MD2B with direct seawater cooling (bearing in mind the cost of Volvo spares) compaired to a BMC 1.5 which has had corrosion inhibitor in the block.

As some of the other posting have said, it just not the cost of the engine, there is the engine bed, exhasut pipe, instrumnetation and propellor to change.

As I said, keep the engine and give it a new life,

John C

 

[Forbsie]

You can also find spares Tender to...

 

[willtaylor]

Thanks for all the help so far. I am inclined to keep it. I was already. It goes quite well and my surveyor was a very meticulous man who nevertheless said the motor would go on. he suggested it might need rings.

 

[colvic]

Don't scrap it, as it is the old tractor engine, built for the purpose of running for hours on end. Our twenty year old one has done great service covering over two thousand miles this year alone.

AMC diesel in Preston are very good as well as ASAP spares, BUT depending on where you live I found a superb pair of old mechanics who've worked on this engine since it was introduced. They can also overhaul and service the injector pump cheaper and better than anyone else I've tried.

A modern replacement, such as a Beta Marine 39 would cost in the region of £9000 to be fully fitted...just had a quote for insurance purposes!

If you want more specific details contact me


Phil

 

[chas]

I have a love hate relationship with my T90. The head has been off, the fuel distribution pump and injectors overhauled (local CAV agent - excellent job at a reasonable cost and much help and advice) and most of the fuel pipes replaces (ASAP - very cheap and helpful). Just put a new freshwater pump on (ASAP again - about £36 as opposed to quotes of £70 from elsewhere). They have their quirks (I cant take the FDP off without taking the starter motor off and thet requires the fuel filter to come off!) and be VERY careful if you are taking glo plugs out - break one and the head has to come off!

The engines have a reputation of being bombproof and I would certainly go a long way to repair or recondition mine before I replaced it.

 

[stubate]

to do rings is quite straight forward, but it is engine out, head off etc. if the rear oil seal is leaking donk really needs to come out to fix it. depends how much the probs bother you, cost of putting a pint of oil in now and again ???
if you do decide to remove give us a shout for online help
stu

 

[PeteMcK]

Keep it

Your choice at the end of the day, but to change it for a similar sized new engine will cost up to about 10k. I've no intention of replacing mine. All the parts are readily available (and at a small fraction of the equivalent Volvo prices). How much oil do you use? Mine burns and leaks about a pint per 100 hours - that's well inside its new spec. A good mechanic would charge under 1k for an "as new" overhaul of the core engine, including rebore and new pistons: another few hundred would cover renewal of all the ancillaries and overhaul of the injection gear. That's not a bad downside to live with. If it ain't broke, definitely don't fix it: DO keep an eye on it, esp. oil and water levels, temps, pressures, until you're happy it's ok. You're quite right, the ancillaries, as with any older engine, are the most likely source of trouble.

And it's a much older design than the Marina. The base engine was used in the smallest of the Leyland tractor range, the taxi version of the Morris Oxford and, probably its biggest single use, in the GPO's flat fronted J4 mail vans. In its slightly bigger 1.8 litre form, it went into the Sherpa vans (and most late 80s up to early 90s Moodys). The vast majority of the thousand or so Moody 33-1,2,3s built still have their original T 90s. Anyone who knocks it because of its BMC ancestry, frankly, hasn't a clue.