toad
New member
Hi does anyone know if a Thorneycroft 90 oil filter head assembly is the same as a BMC 1500.
Ta
Ta
Thorneycroft/bmc 1500
- Thread starter toad
- Start date
maxi77
Active member
As the Thornycroft T90 is the main marinised version of the BMC 1500 diesel it is highly likely. You could speak to ASAP or Thornycrofty Parts who both know the engine well. Thornycroft Parts recently sold me a spin on converter for the T90 which worked well.
toad
New member
Thanks for that, this is the route I would want to go down, this is a friends boat who I was helping change the oil and filter on last weekend. When I removed the old filter I noticed that there was no oil pressure relief valve just a hole and no bits in the canister. So no oil filtering has been happening for a few years, I spoke to Thorneycroft today and was told parts were no longer available but did not think to ask for a conversion head. There is one on EBay for £50 for a BMC 1500 that looks right so I think its worth a go.
pampas
New member
My old BMC has a vertical can the element is a tall cylinder no pressure valve inbuilt, obtainable from most auto factors or Farm Industries, relativly cheap,the pressure valve being built into the base casting.Does this help?
toad
New member
Yes its the base casting that I need,worryingly the engine was rebuilt by a marine engineering company about four years ago and all my friend has done since is change the filter each year, I think even she would have questioned a ball and spring laying in the bottom of the canister.
Boo2
Well-known member
Ah, close : the Thornycroft 90 is the marinised BMC 1500, the T90 is a marinised Mitsubishi. Even thornycroftparts gets this wrong
Boo2
pampas
New member
Scrap yard seems to be the best bet for older engines,sad but true.
maxi77
Active member
Ah, close : the Thornycroft 90 is the marinised BMC 1500, the T90 is a marinised Mitsubishi. Even thornycroftparts gets this wrong
Boo2
Now there was me thinking the Mitsubishi one was the T80
Boo2
Well-known member
I think the Txx are all Mitsubishi but don't quote me on that. There's a list of the Txx engines here : http://www.diamonddiesels.co.uk/thornycroft_ref.html but it doesn't show a T80 ?
Boo2
theoldsalt
Active member
View attachment 31121
I think that the Thornycroft 90 and Thornycroft T90 are the same engine. Sometimes with Thornycroft engines the 'T' gets omitted. So on the Diamond Diesel web site the '80' is actually the 'T80'
I think that the Thornycroft 90 and Thornycroft T90 are the same engine. Sometimes with Thornycroft engines the 'T' gets omitted. So on the Diamond Diesel web site the '80' is actually the 'T80'
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Boo2
Well-known member
I don't think that is true, I think there is a newer T90 based upon a Mitsubishi engine as well as the older 90 based upon the BMC 1500. This has cropped up before these forums.
Note that even thornycroftparts / thornycroftengines get that wrong (AIUI they are not the original Thornycroft who marinised the engies but just a parts supplier). Here's a pic of the original manual showing the BMC 1500 really is a Thornycroft 90 not a T90 :
Boo2
View attachment 31123
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maxi77
Active member
It does however show an 80 and no 90 with or without a T and Thornycroft used to offer Mitsubishi 80s configured to fit directly in place of BMC 90s
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maxi77
Active member
In fact until a few years ago they were called Thornycroft and did in fact convert and sell the Mitsubishi engines and would do a trade in deal for your old engine, as I did consider it some 4 years ago. As far as I am aware the present Thornycroft parts is the rump of the old Thornycroft engines which was bought by an Indian company a good few years ago. India is a massive user of smallish industrial/agricultural diesel engines
theoldsalt
Active member
Perhaps someone else could compare the manual for the 90 with the manual for the T90. To me they look very similar and both appear to be BMC 1500.
I have not heard of a Thornycroft T90 with a Mitsubishi block.
I have not heard of a Thornycroft T90 with a Mitsubishi block.
TNLI
Active member
The scrap yard will be the best bet for modern engines for sure, unless they are expensive German electric motors!
Yanmar are probably the worst offenders in my opinion, as they can be very expensive to rebuild when some expert operator runs one out of oil, fails to change the oil, fits the wrong prop causing a valve to snap off from over torque and the most common one of all, suffers a head gasket failure due to an expired warranty. If you use too low a power with many modern engines the cylinders start to foul up leading to bore glazing issues. The same low power foul ups can happen with older classic diesels, but it's not an expensive fix in terms of parts, or alternative varnish removal methods using acetone, (Only works if you deal with it before the valve guide oil seals are involved).
Rant over, and back to the question about oil filters. It seems there are 3 types of oil filter installations on a BMC 1500, that was used for the associated Thornycroft lifeboat or sailboat engine, which is now back in production. Firstly some older BMC's had removable canister type oil filters where you unscrew the can, drop oil all over the place, inspect the element to see if it needs to be changed or even cleaned using Bio diesel if available, (It's a better solvent of sludge), and then refitted with a new oil seal. Dirty oil filters are far more efficient than clean ones, until they are so sludged up that the bypass valve, (It's in the BMC block), opens, which it does for a short time during cold starts due to high oil pressures.
Alas Mr Morris decided to go with the oil flow, and fit spin on canisters thar can't be inspected, so we get a version no 2. Finally some BMC 1500 blocks were modified by fitting a conversion part into the old push in canister location, so customers could improve their image by using smaller spin on filters, (They need changing more often, due to smaller element size). I think they even moved the oil pressure relief valve inside the back of the can, just to allow anyone who tries to use a far Eastern copy of a BMC oil filter, to blast the entire can off the side of the engine when it fails to open during a real cold start!
No idea if the Thorny 1.5 uses a spin on oil filter, but ASAP do list Thornycroft parts, so it's easy to figure out which oil filter is used. I love the BMC 1500 block, and I think it's great to see Thornycroft diesels in production again. Both the BMC 1500 and the Thornycroft version in particular, have a serious cult like status in Blighty, or in our wonderful Commonwealth countries, like India, where they still make BMC parts.
Long live the BMC 1500 and the Thornycroft 1.5.
I will now stand and sing, "God save the Queen"!
PS: For those folks in the USA that admire the BMC 1500, WESTERBEAK (Iffy spellin), are like Thornycroft, they also use a BMC block. They only seem to make one diesel, and it has a modifyed governor that reduces the max HP from 35 to 30hp. So those Yankee boat diesels do indeed last forever and a day. They might well have been designedto run dry standards, where the manufacturer has to prove that running out of oil or coolant does no real harm at full chat, although they are allowed to use oil additives to help prevent the engine siezing.
I've read the specs of a similar miltary gen set diesel, and the oil had Liqui Moly Ceretec added every oil change. That additive contains 200ppm of high grade Moly, (Mo), AND a hexagonal form of Boron Nitride, which is a ceramic. In ultra fine particle form it's incredibly effective at coating bearings and upper cylinder parts. The combination of the 2 allows the engine to run dry in oil terms. There is also some type of additive in the coolant, but no idea what that is, although it might be some type of soluble sealant, designed to keep the HG sealed up and functioning correctly. If it's a ceramic particle additive, there is a company in the USA that makes a HG sealant that really does work, and does not block up the heater matrix like the cheaper Bars products used by many dodgey used car or boat engine experts.
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TNLI
Active member
That type of Thornycroft is now in production by Marine Enterprises Ltd in Dorset. Not sure if they are going to make any Thornycroft 1.5's, as the BMC block is no longer available. They did recondition a few, but they got sold before I had a chance to call the CEO Sean.
Ink
Active member
I know this thread has had the Lazarus touch, but just for completeness :
Thorneycroft/T90 is BMC 1500
Thorneycroft/T80 Mitsubishi KD4 35hp
Thorneycroft/T95 Mitsubishi SL4 39hp
Regards
Ink
Thorneycroft/T90 is BMC 1500
Thorneycroft/T80 Mitsubishi KD4 35hp
Thorneycroft/T95 Mitsubishi SL4 39hp
Regards
Ink
Jim@sea
Well-known member
I bought a boat with a BMC Thornycroft engine purely because in the 1970,s I sold Austin J4 Vans and they had these diesel engines in them.
I made a mistake though as I thought that as MGB engine parts are readily available, so would the BMC Thorncroft parts.
I wanted a new or reconditioned water pump but could not find one. Yes I could get one if I sent my old one off but I wanted a spare in a box.
I made a mistake though as I thought that as MGB engine parts are readily available, so would the BMC Thorncroft parts.
I wanted a new or reconditioned water pump but could not find one. Yes I could get one if I sent my old one off but I wanted a spare in a box.
Graham_Wright
Well-known member
Boater Sam
Well-known member
To my knowledge there were 3 slightly different water pumps used on the BMC 1.5D. The MGB pump is one of the 3. This one is the same AFAIK as the BMC 1.8D pump. But as far as I know all are still available from factors. The other possibility is the Marina "B" engine pump but I have not tried one.
ASAP and Calcutt should both be able to supply you.
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