Engine & Cylinder Head Numbers Mismatch

[ramjam2005]

Just preparing to clean and hopefully un-seize my engine which has been sitting out of the car for a decade or more so I took the opportunity to check the engine number which has now left me a little confused.

So, as a reference my Stag is a 1972 Mk1 M/OD commission no.LD118520. Cleaned off and noted the engine number - LF30647HEA - which differs from the V5. Not surprised there as I had a reconditioned engine fitted back in the 80's by The Stag Centre in Hackney, so it was more curiosity on my part to see if they had used my block, hoping I would have retained matched numbers on the V5.

What is confusing is the engine suffix of HEA relates to High Compression 65 AUTO, yet my car is Manual with overdrive. Is there any significant difference to a HEA? I would have thought the only difference would be the block to gearbox adaptor plate used.

Second part of the confusion is the high sequence number would possibly indicate the block originated from a Mk2 commission number car yet information gleamed form a forum search would indicate I have Mk1 heads fitted with the sequence numbers 307872 and 3. So what sort of Frankenstein's monster have I as an engine ?

I also noted another number lower down on the side of the block just above the sump line - 88309123 V3176. What is this number?
Any info gratefully appreciated.

Ray

[StagJonno]

Engine numbers on Mk1 were on the side. Mk2 had them at the back, around/ below where the coil normally sits. I thought the HEA indicated a factory replacement engine, but don't confuse me with an expert!

"88309123 V3176" are, I think, Stanpart casting/ part No references. Can't get to see the block markings on mine, but I do have similar format markings on the cylinder heads 88313210 V3294 and 88313211 V3293 (these are Mk2).

Jonno

[flying farmer]

Engine blocks don't differ between manual and Auto.
If Mk1 heads have been fitted to an engine with Mk2 domed pistons you have a very high compression engine as the heads had smaller chambers.
That depends on what pistons it was fitted with as you say it was a reconditioned unit. It may have been fitted with Mk1 pistons, and these are the only ones available these days, though that may have been different back in the 80s.
Mk1 and mk2 engines have different distributor advance curves, and these need to be matched to the type of pistons fitted.
Neil

[mole42]

Mine is a later engine, 21162 which was changed in 1985. It has Mk1 heads and Mk1 pistons.

[DJT]

Engine numbers on Mk1 were on the side. Mk2 had them at the back, around/ below where the coil normally sits. I thought the HEA indicated a factory replacement engine, but don't confuse me with an expert!

"88309123 V3176" are, I think, Stanpart casting/ part No references. Can't get to see the block markings on mine, but I do have similar format markings on the cylinder heads 88313210 V3294 and 88313211 V3293 (these are Mk2).

Jonno

Very early Mk1 engines had the number on the side. Most are on the rear upper part of the block.

V31** = Mk1
V32** = Mk2

HSS were factory replacements.
HEA BW65 auto

[ramjam2005]

Engine blocks don't differ between manual and Auto.
If Mk1 heads have been fitted to an engine with Mk2 domed pistons you have a very high compression engine as the heads had smaller chambers.
That depends on what pistons it was fitted with as you say it was a reconditioned unit. It may have been fitted with Mk1 pistons, and these are the only ones available these days, though that may have been different back in the 80s.
Mk1 and mk2 engines have different distributor advance curves, and these need to be matched to the type of pistons fitted.
Neil

Cheers guys for your input.

Neil, I did think that i.e having Mk1 heads would mean matching with Mk1 pistons. With the shallower chambers I didn't think Mk2 domed pistons were compatible (i.e valve clearance)? IF I do have such a combo giving a very high compression would this not lead to higher running temps ?

The engine ran perfectly before being laid up and I did regularly turn it over on the starter motor with no spark until it was removed. I'm hoping I can free the engine without a strip down or heads off so won't be able to confirm unless the latter happens.

Anyone got any advice/precautionary steps on freeing the engine? So far I'm giving the pistons/bores a few days soak of diesel oil thru the spark plug holes but was contemplating rotating engine on the stand removing the sump and liberally coating the crank/shell bearings with assembly lubricant or engine oil as been dry for many a year - similarly with the cams. And what about the notorious jack shaft seizures?

Ray

[mole42]

If the engine is out of the car, I would strip and check lots of things before I thought about trying to run it. As it has been idle for "a decade or more" there are likely to be problems which would be easier to sort out on an engine stand than in the car. I once bought a 'new' Triumph 2.5PI engine from a Technical College that had never been run but was used to learn tappet setting. I fitted this to my 2.5PI Estate and used it for a few months quite happily, until one of the piston rings broke and destroyed No6 bore. The rings had siezed during their ten years of idleness....

It seems like doom-mongering, I know, but if you strip the engine and check everything, at least you'll know it's okay before you put it back in the car.

[jakesmig]

Nothing to do with heads / block numbers, but I saw a 'salvage' type show with Sugs and others where an old hand unseazed a really stuck engine by pouring boiling water into the cylinders and leaving to sit for a while. They had tried all the usual tricks of forcing with a long lever, oil down the blocks, penetrating oil etc without any movementbut the hot fluid did the trick. If I recall correctly it was the engine of a Gypsy Moth they were trying to sort.

John.

[jakesmig]

Wrong fluid, it was oil they heated up.

https://www.youtube.com/watch?v=tivUXdrA8zE

16 minutes in.

[Guest]

HSS were factory replacements.

NO SS means SPARES STOCK.
They were usually "snagged" off the production line for a quick QC hit (quality control), and that meant lots of them were actually REJECTS.

Most people don't realise the vast majority of Triumph spares stock, particularly the wonderful "beans industries of Tipton"specials were rejects or relapped odd crown and pinions, remarked and then sold as new...

Been there done that, rebuilt lots of SS engines and axles!

You should see the crappy TKC brand new NOS cylinder heads I had.
Lots had the stud holes machine out of line with the cylinder bore centres....caused chaos and destruction that did!

[flying farmer]

Cheers guys for your input.

Neil, I did think that i.e having Mk1 heads would mean matching with Mk1 pistons. With the shallower chambers I didn't think Mk2 domed pistons were compatible (i.e valve clearance)? IF I do have such a combo giving a very high compression would this not lead to higher running temps ?

The engine ran perfectly before being laid up and I did regularly turn it over on the starter motor with no spark until it was removed. I'm hoping I can free the engine without a strip down or heads off so won't be able to confirm unless the latter happens.

Anyone got any advice/precautionary steps on freeing the engine? So far I'm giving the pistons/bores a few days soak of diesel oil thru the spark plug holes but was contemplating rotating engine on the stand removing the sump and liberally coating the crank/shell bearings with assembly lubricant or engine oil as been dry for many a year - similarly with the cams. And what about the notorious jack shaft seizures?

Ray

Mk1 heads have smaller chambers but not shallower so no difference in valve heights.
Higher compression actually makes an engine more efficient so it would actually run cooler rather than hotter provided it is set up right.

I wouldn't even think of not stripping the engine down if it is out of the car.
Cam buckets often corrode after a long lay up which will do the cam bucket bores no good at all if it is run. Rings often rust into the bores but sometimes can be freed off with a lot of patience.
The Stag engine in the TR was just like this, it was bought as a non runner but turned out to have had a full rebuild before it was laid up. One valve was bent because a corroded bucket had stuck, and one piston was corroded in the bore. I saved the piston, and even the rings although I had to have a liner fitted to that bore. All it needed in the end (apart from the liner) was a gasket set and a new set of cam buckets and I replaced the valve springs as I was fitting uprated cams.
Don't even think of not replacing all the core plugs even if they look ok on the outside as it is a serious PITA removing a head to replace a leaking one BTDT!

I once made the mistake of running an engine after a long lay up (it was in the TR6 I once had, stood for 8 years)
It had only done 58,000 so I thought it would be all good at the bottom end. I had swapped the head and converted it to injection (it was a USA carb version). When I changed the oil after 500 miles I found the filter had collapsed under the volume of crap that had fallen out of the inside of the block. I ended up taking the sump off and found all the bearings were down to the copper backing despite the 50psi hot oil pressure, fortunately the crank was still good.
Fitted new bearings and seals and found hot oil pressure had risen to 80 psi and in the end it was a really good engine that ended up in my current TR until I fitted the Stag engine. It ould have been a damn sight easier to have done the job properly in the first place and I wouldn't make the same mistake again.

Neil

[Kithmo]

Wrong fluid, it was oil they heated up.

https://www.youtube.com/watch?v=tivUXdrA8zE

16 minutes in.

Get the chip pan on dear

[ramjam2005]

Strip down it is then. Many thanks for all your replies.