Morris Minor Owners Club

I have the motor (original motor from 7/3/49 despatched tourer) rebuilt and running nicely in the car..... except I have a 'prolific' leak from between motor and gearbox. When i put the motor together the scroll on the crank looked good and I put a feeler gauge between it and the alloy bit etc and while i can't quote the number, my experienced cousin said that was good. I got this motor with all sorts of machining done and the words from my mate who was very experienced and had a business building racecars and restoring and had that done that it was all ready just to bolt together. He had brain cancer at the time and not thinking that clearly perhaps, but my cousin with something like 55yrs experience doing his apprenticeship and working most of his life at Adelaide engine service a major rebuilder.... helped me put it together and i thought I was all covered with him checking and advice... but then he wasn't that well and died weeks after we finished. So I am running a bit short of people to ask at the moment.

I started it, had a problem including the leak and had to drop the sump again and so i could look up and see that the area and on the freshly 'blasted' (looks like that water blasting or whatever they call it that they use on alloy) alloy sump under the main bearing and it was all dry. Where it was oily and you could see it had run down was on the cam side of the motor and I thought I must have somehow made a bad seal with the gasket there (silly in hindsight because there was much more oil than would leak from there). Sump back on, motor sounds particularly sweet but after something like 30 sec of running I went back in the pit and oil flowing out the hole at the bottom.

Thinking again, and very annoyed with myself, surely the position of oil leak and volume must be under pressure from the end of the cam. The exploded diagrams in my workshop manual don't show any sort of plug there, but then i thought logically that they had to linebore for the camshaft so surely there must be a hole there. There is a later water pump SV engine there so I pulled the sump on that, flywheel bolts and then fought for ages trying to get it out between the block casting and the pins in the end of the crank (ridiculous!!) and sure enough there is a welsh plug looking thing there. I just don't remember the area when i built the motor. Are those plugs available to buy? Seems hard to get any SV parts generally. Any other thoughts.

I don't think i have a lot of options other than to pull driveshaft, gearbox, sump and battle with that flywheel to get in there and look. If it ends up it is the scroll then the whole motor has to come out anyway and try and get that clearance right. Right now I can't wait to get back on to cars I know better!

Thanks Rob.... just came on to update...... I need a new welch plug! Any ideas where to get one? Been googling and not having any luck. Do you know what one looks like out of an engine?

Search welch plug on ebay for pictures and availability.

Use a brass core plug if possible & you should be able to find what you want from here:

https://coreplugs.co.uk/brass-plugs

They do core/welch plugs in other materials & in imperial and metric sizes too.

Thanks Ian - first thing i did but perhaps searching from Australia (that usually has lots of uk sources) has less - only saw a set for block but no confirmation of size and referred to 2 plus spare for block - figured probably for 2 in water jacket. Thanks too Phil and that would seem to cover it. But thinking the 'bird in the hand' theory, this afternoon I stripped the cam out of the spare motor and put a big brass drift in and popped the part out without damage. 45mm. Now just a matter of pulling gearbox etc etc.

And still on the topic of sv experience - are there any tricks to getting the flywheel off easily over the pins in the crank with the ring gear teeth wedged against that flange for gearbox on the block. My pins were flush with the flywheel - maybe i should file them shorter but flush would mean max strength - or maybe strength is in the bolts and pins are really just locating so it is perfectly centralised? Just seemed odd to me why such a simple task would be made so difficult and that surely i am doing something wrong. Only other way I could see is if you are supposed to mount the flywheel to crank and install as one piece.

As regards using the core plug from the spare engine.

Personally I would not use a previously fitted core plug because:-

1. The core plug will have been fitted to the hole it came from and not the hole it is going into.

2. The core plug will have been flattened when fitted for the first time and it will be virtually impossible for the core plug to regain its original shape to be of use the second time around.

You may find that after all the work and effort the pre-used core plug still leaks.

If required in an emergency - yes use - but if non urgent get a new core plug (preferably brass) and then you can be sure that you have done the job right.

Phil

CPI is a good source for core plugs -thats where I buy them too and I would also recommend installing the brass plugs.
Their postage is also quite reasonable.
Regards
Declan

https://www.ebay.com.au/itm/45mm-Stainl ... :rk:1:pf:0

https://www.ebay.com.au/itm/45mm-Dish-t ... :rk:5:pf:0

Any good?

Thanks for all that - yes the dish type one looks the right shape Rob. And just questioning the brass suggestion, given this is holding back oil and not water, what would be the advantage of brass? Easier to installl - ie. softer - or just a general rule go for brass re corrosion.

Whilst you are correct that the core plug is only holding oil within the engine it is preferential that brass core plugs are fitted in all cases.
I would suggest that production costs prohibit the fitting of brass core plugs in most cases so the fitting of brass core plugs is a quality assured improvement to reliability.
The brass core plug being made from softer material will form to the core plug hole in the block much easier.
The softer material will not compromise its strength or ability to do its job.
Once fitted brass core plus are a fit and forget item unlike its steel counterpart.
The cost of the brass core plug (£2.03 against £0.83 for the steel) is well worth it for the additional piece of mind.
Phil

Thanks Phil - I felt pretty sure there was going to be very clear reasons - thanks for educating me!