Clearing the block

[Dougie212]

Hello all

I’ve just taken my cylinder head unit off to send away for refurbishment.
Exposing the top of the block I’ve discovered what I think are some mucked up ports which I think may be a further symptom to the water problem I’ve had - in that… no water drained from the block drain tap, and it was bunged up with junk.
I guess I’m hoping that I don’t need to take the block out too but if necessary I will. I was sort of hoping I could clean the surface off with it still in the car.
I’ve attached a pic.
Any suggestions would be hugely appreciated as always.

Thanks
Duncan

[svenedin]

You can certainly clean that up. I did mine a few months ago and it came up well .

First take all the studs out. You can use the 2 nut method to do this. Screw one nut on and then screw a second nut on. Using 2 spanners tighten the nuts against each other. Then using a spanner on the bottom nut remove the stud.

Now stuff the cylinder bores with rag or paper towel and using a green plastic scouring pad clean the top of the block. Using a liberal quantity of WD40 as a cleaning agent/lubricant helps.

Check each stud hole for pulled-up threads and if in any doubt lightly countersink the stud holes taking care to remove any swarf (again use WD40).

Looking at you photo I would also suggest replacing the neoprene tappet chest gaskets and remember there is a rubber cup washer on each to replace as well.

I wonder why your piston crowns have such localised scorch marks?

Stephen

[philthehill]

The engine block is a 948cc gold seal unit so will have the cork gaskets fitted to the cam follower aperture covers as per the photo. The washers that go under the bolts holding the covers to the block are fibre washers.
The 1098cc covers are of a different design and have neoprene gaskets and neoprene washers fitted under the cup washers of the cover holding bolts.
The covers are interchangeable but there is my opinion not much gained by fitting the later covers. Do not over tighten the cover bolts. Grease the cork gaskets before fitting.
Run a suitable drill down the coolant transfer holes in the block to clear the holes. Flush the engine after rebuild and cleaning the transfer holes.

[Dougie212]

Brilliant!! Thank you both!!

I’ll set to it over the weekend.

[svenedin]

Phill is right about the tappst chest gaskets and washers of course. I hadn’t realised it was a 948 block.

On my block I also used a scraper of the type with a mounted Stanley knife blade. It is for scraping paint from window glass. It worked very well and also detected pulled up threads in the stud holes by catching on them. Just use the scraper carefully so that you don’t gouge the block. Pulled up threads could cause a new cylinder head gasket to fail.

Stephen

[ecifiedthyt]

In the event that you are unsure, softly countersink the stud holes, taking care to remove any swarf (once again, use WD40). Check each stud hole to ensure that the threads have not been pulled up.

[myoldjalopy]

The engine block is a 948cc gold seal unit so will have the cork gaskets fitted to the cam follower aperture covers as per the photo. The washers that go under the bolts holding the covers to the block are fibre washers.
The 1098cc covers are of a different design and have neoprene gaskets and neoprene washers fitted under the cup washers of the cover holding bolts.
The covers are interchangeable but there is my opinion not much gained by fitting the later covers. Do not over tighten the cover bolts. Grease the cork gaskets before fitting.
Run a suitable drill down the coolant transfer holes in the block to clear the holes. Flush the engine after rebuild and cleaning the transfer holes.

According to ESM, the neoprene types are suitable for 'all OHV engines': https://www.morrisminorspares.com/engin ... ll-p830243
They also sell the cork ones said to be for the 'convex cover'. So my question is which will be best, as I need to replace my gaskets soon due to an oil leak from the covers?

[philthehill]

The two seals are for two different covers. The neoprene seals can be made to fit the earlier covers but it is better if you fit the cork seals to the covers you have. Glue the cork seal to the cover and then grease the mating faces before fitting.
You will need the cup washers to go under the bolt heads as well as the neoprene seals that go under the cup washers.
The cover holding bolts are different to accommodate the different seals.
So to recap my advice is to fit the cork seals to your covers not forgetting the fibre washers that go under the bolt heads.
See the MOSS link for details and part numbers
https://www.moss-europe.co.uk/shop-by-m ... 51-71.html

[myoldjalopy]

Hello Phil. Surely the existing cup washers can be re-used?
And so: bolt head, fibre washer, cup washer and then neoprene seal before the covers?

[Sleeper]

P.S. If you're not taking the block out don't forget to block up the stud holes , oilways and pushrod holes before any action..

John ;-)

[philthehill]

There are no factory fitted cup washers to the original covers unless someone has fitted them post factory.
If you have cup washers you do not need the fibre washers.

[myoldjalopy]

Thanks Phil. I'll take a look. The job itself can wait until I decide to replace the rattly exhaust, although I've got so used to it now it hardly bothers me Its possible the cup washers are present as the engine was re-conditioned by a local firm about 16 years ago.
'Ave 'ee got any Tribute in fer Chrissmus yet, boay?

[philthehill]

Well stocked up with Tribute and Proper Job.
When competing at the Tregrehan Speed Hill Climb, St Austell in the 1970s my main watering hole was the Ship Inn at Pentewan just outside St Austell.

[myoldjalopy]

Gwra aga omlowenhe, Phil! (Enjoy them, Phil!)
The pub is still there as well!