Woil

[davidwheeler]

Unfortunately, said hole is the main drain for the block!   Now I shall have to drill it our again.    I have dropped the sump and cannot see an obvious leak.

[donw]

I had an engine block sealed but the company I used is no longer there but I found this one that might help

https://www.surfacetechnology.co.uk/casting-impregnation-services/

[davidwheeler]

Yes, I had found them.   Unfortunately I am half way between Aberdeen and Slough.  The other block is currently in Manchester being repaired so I shall ask them if they know of anybody a bit nearer.

[davidwheeler]

Doubleplus unprogress continues.     I have taken the engine out of the car.    I cannot see any holes in the interior of the sump nor in the bottom of the water jacket.   I have even blasted it with my pressure washer and not seen any water coming through.   There are four brass plugs which seem fine.   The head is aluminium and a test fill of that did not show any leak.     I am left to surmise a leak via the head gasket from water hole to oil drainage channel.   It is unfortunate that I did not take of the sump when I was testing the intact engine minus water pump and finding water going through into the sump.     Where, classically, do Lambda blocks leak?  I dimly remember soneone saying round the base of the cylinders but I see no sign of that.

[donw]

at the bottom of the V where cylinder liners almost meet

[davidwheeler]

I cannot see anything amiss there.   However, I obtained some 2 pack floor paint mixed it up and poured it in.   Unfortunately, in my frigid workshop it failed to solidify.   Today I have been warming the block with two electric fires and a hot air gun, finishing by directing the infra red rays into the underside of the block.   The paint now seems to have gone off so tmorrow we shall proceed with re=assembly.

[lancialulu]

Do you think 2 pack floor paint will adhere? I know from experience it "blows off" easily if the substrate below has any damp causing vapour pressure.

[davidwheeler]

I hope so!     I think it was pretty dry within having blasted it with hot air from above and below.

I fitted the sump and filled the block again with water and watched - for several days.   The water level did not go down and there was no water in the sump so, yesterday, I convinced myself that there was not a leak in the block and installed the flywheel (a task requiring the use of a magnet on a stick and thin fingers - much easier if done before the sump is installed), the re rebuilt water pump and the oil pipes.   Today I put the engine into the car.   Hooray for electric lifts, much easier than my engine crane, followed by the dynamo/distributor (not the magneto, I have converted to coil) and tidied up various wires and the wiring covers along the side of the chassis frame.
We make progress.
I have decided that the leak was via the head gasket.   It was a thinner gasket than I usually use and the locating ring at the back of the block is perhaps just a little too thick allowing water eventually to make its way through to the iol drain pipe.   I'll fit the head and do another leak test before going any further though.

[davidwheeler]

Put the head back on.    Cleaned the faces with thinners as my gasket is made from compressed carbon which adheres very well to clean surfaces (with copper liners of course) and filled the engine with water.     Discovered a leak along the 5 o'clock screw on the face of the water pump and sealed that with Hermetite.   I shall leave it to settle and re-torque it in a day or two with, I hope, an "official" torque setting (see above).   The water level may go down a bit though  do not see any external leaks.   So long as there is not any water in the sump I shall be happy.

[davidwheeler]

Found this morning that half a gallon of water had leaked out - but not into the sump.  'Twas a little drip from a rubber pipe.
Felt confident enough to start reinstalling the gearbox.   Had to use the engine hoist as electric hoist in the wrong place and all a bit of a struggle.   To think that in 1972 I stripped the clutch in the car park of the Carlo Biscaretti Motor Museum using a jack and a concrete post to compress the spring and a loop of rope held while sitting on the scuttle to lift the gearbox in and out.    I guess I am not quite so strong as I was...

[davidwheeler]

Today opened the sump drain tap and found a cylinder head's worth of water within.  Aaaaaargh!
"Off with its sump" (as the Queen of Hearts did not quite say).   After a cup of tea I crawled underneath to find water dripping - apparently from the outer edge of the bottom of the cylinder liners of the front two cylinders.
BUT, stuffing the cylinders from underneath with cloth stopped the drip.
I have inserted strips of rag through the plug holes and will go and look in the morning to see which bits of rag are wet...

[davidwheeler]

No 1 cylinder full of wet rag and water and the rag beneath also soaked.   Applied air pressure to the plughole with the valves closed and water poured out of the radiator hoses so peoblem is in the cylinder itself, perhaps eithin the combustion chamber.
"Off with her head!" as the Queen of Hearts did say - but not today as I shall have to go into the pit and remount the prop shaft before I can roll the car underneath the electric lift and it is cold and wet out there!
To be continued...

[davidwheeler]

"Curiouser and curioser" said Alice.
No ! (i.e.the front) cylinder has clearly had water in it but none of the others - but there is no clear route for its ingress.   No cracks or devects in the combustion chamber nor in the top of the block.   New gasket.   Both surfaces seem flat.
So, coat the gasket copper liner with red Hermetite, put the head back on and fill with water...

[Dikappa]

David,

Could it be there is a leak to inlet or outlet channel in the head, and that is thus comes via the valves?  Do you have an inspection camera?  I bought one of these cheapish things on internet but it works very well, maybe that might help inspection?

[davidwheeler]

I think not.   This morning there was no sign of leakage whatsoever despite the anterior (?exhaust) valve being open a touch.   I closed the valves and applied pressure to the cylinder via the plug hole and there was an effusion of water from the head via the radiator feed.      The leak must be in the combustion/cylinder.
I removed the head but there was, alas, no clear indication of the locus of the leak.      I have a mirror to which I have glued some 400 grade emery paper and that showed the head surface to be pretty well flat.    I took out the head studs and did the same to the surface of the block which is a little less flat but no great irregularity.     Tomorrow I shall glue some 150 rade to another, thicker mirror and see if I can flatten the block surface.