Running in - Leak problem !

[m.hunter]

Hello all !
Greetings from Germany ! Yes, there are quite a few of us over here getting our hands very dirty trying to keep our Moggys alive and kicking!

I`ve run into the old problem of oil leaking from the rear crankshaft. After first seeing this, I checked the breather pipes and that I had the correct mesh oil filler cap. There isn`t an vac. inlet on the carb for the breather pipe so it goes onto the airfilter. When I took the oil fillercap off there was no change in leak-drip speed. All OK there. I then read in one of these threads that a worn crankshaft/bearing shells/Thrust washers could also cause play through which oil could escape( and noticing that there was a light knocking coming from the crankshaft) I decided to get a new one. Once the engine was stripped, I inspected the bores which were quite shinny but measured perfectly round and undamaged.I honed them all (is that the right word?) and fitted new pistonrings. After fitting the new crankshaft and all bearing shells, I fitted a new oil pump, timing chain, waterpump, new valves, springs & seals and a rear crankshaft sealing kit.
So, after putting everything back together, now I`m running her in for about 800Kms with the special Running in oil. We`ve coverd about 200 of the said 800Kms and the oil leak is still going strong, as if I hadn`t spent the last 3 weeks and hundreds of Euros on her!?

Is it normal whilst running in, untill the piston-rings are beded in, to loose excesive oil? The running in oil is very thin. After a 30 Km ( 20 Mile ) run, if I park her up over night, there will be a 4-5 inch diameter puddle!

Just point me in the right direction !

By the way, she is a LHD. 1957 4 door saloon with a 1098cc engine.

[downsey]

I have no experience with the rear crankshaft seal but others have said that its basically a flip of a coin as to if it will be succesful in stopping the oil leak.

[bmcecosse]

There is no doubt that having vacuum connected to th block cuts down on seal leaks in general - but sould not be necessary on a re-built engine - and yes 'honing' is correct. You need to determine where the leak is emerging - is it from the rear seal on the sump pan (directly dripping from the sump) or is it from the rear crank seal (dripping from the gearbox hole with split pin). I'm intrigued by your 'rear crankshaft sealing kit' - and if it's not doing it's job you should go straight to the supplier (who was it ?) with a complaint!

[Kevin]

The running in oil is very thin

Thats not needed with the A series engine normal 20w50 is fine for running in, the oil you are using may just be too thin and making the leak worse.

[m.hunter]

[quote="bmcecosse"]There is no doubt that having vacuum connected to

Thanks for the reply, the oil leak is coming directly from the rear of the crankshaft and drips, as you said, from the split-pin. All the other gaskets are fine, including the sump. I think I`ll change the oil to the standard 20/50 in the morning and maybe take the thermostat out ( she seems to be running a little warm) and maybe advance the timing a bit.

Silly question : Do you think, if I were to put a small 12 volt hoover in the boot and conect it via piping to the tappet chest breather outlet, it would stop the oil leak alltogether?
Another silly question : What would happen if I were to drill the both sides of the sump at the top, and weld a pipe onto each side coming straight up to the level of the oil filler cap, say 15mm diameter? Would things become very wet and soggy?
I`m just so fed-up of stripping the engine and getting nowhere

Thanks again for the posts.
PS. The rear seal gasket came from E.S.M.

[bmcecosse]

Rear seal gasket ??? Where does that go ? The rear seal should just be a semi circular piece bolted on (3 bolts) the rear edge of the block and matching closely with the similar shape on the rear main bearing cap. These two parts should be a very close fit on the 'scroll' shape on the tail of the crank extension. This scroll is designed to wind the oil back into the engine - and by and large it works very well! It is sometimes possible to slightly adjust the top part to get it best fit to the crank scroll - but there will always be a running clearance. Assuming that's all right - then it's back to the 'thin' oil (forlorn hope I fear) - or maybe too high oil level in the sump - or maybe incorrect main bearing clearance allowing terrible 'flooding' of the rear main - or pressure in the engine. When hot and idling - if you take the oil filler cap off - is there a plume of fume pouring out ?

[m.hunter]

[quote="bmcecosse"]Rear seal gasket ??? Where does that go ?

Sorry, I think they call it a `Rear crankshaft sealing kit`. Anyway, it`s about as much use as an ashtray on a motorbike. When she is hot and the oil filler cap is removed there is no smoke, it does tend to suck a little, as I suppose it should. The Crankshaft has been re-ground - 10" and the relevant shells fitted (again from ESM) no excessive play noticed whilst fitting. Oil pressure seems good, even when hot and drippy!

[bmcecosse]

So - what did that 'crank sealing kit consist of' ? Otherwise - the engine seems fine - if the bearing shells had been wrong size - there would not have been good oil pressure - so have to assume that's ok.
Is this the kit ?
http://morrisminorspares.co.uk/shop/pop ... c307364c9c

[Peetee]

So I'm confused
What is it about the rear seal and it's specifically 'redesigned' replacement that is proving to be such a weak link? Other engines seem to cope without problems so what is it about an 'A' that is proving to be a stumbling block to a efficient seal?

[m.hunter]

[quote="bmcecosse"]So - what did that 'crank sealing kit consist of' ?

Yes, that`s the kit which I bought from ESM. I`m slowly coming to the conclusion that there is blow-by due to slightly worn bores (although, when stripped no apparent damage noticed). So this morning I measured the compression after a total 200kms of running in - will it improve after furter running in?
9.2, 9.3, 9.5, 9.4 all measured in bar from 1 through 4. Should it be higher?
I`ve changed the oil back to SAE30, the running in oil was rather dark after only 200kms ( maybe another sign of slight blow-by ?)

[alex_holden]

9.2, 9.3, 9.5, 9.4 all measured in bar from 1 through 4.

That's 133, 135, 138, and 136 PSI. It does sound a little low. Did you remember to open the throttle while turning the engine over? Do the pressures go up if you squirt some oil into the bores first?

[Kevin]

I`ve changed the oil back to SAE30, the running in oil was rather dark after only 200kms ( maybe another sign of slight blow-by ?)

You really shouldnt use an SAE30 oil as its only a mono grade oil and is not suitable for your engine, its fine to use 20W50 multi grade oil for running in just use a supermarket version and then change it to a better one if you wish.
As a matter of interest quoted from Millers Oils
SAE30 mono grade oil
Very low leak down 4% after running in.
Well if its leaks 4% after running in how much does it leak before and this is in a suitable engine, I still feel you are using an incorrect grade of oil.

[bmcecosse]

But if that kit has been correctly installed- it should hold back any leakage - if not - get on to ESM and demand money back!! You say no plume of fume - so it's not undue pressure. Yes these comp test figures are quite low - but not desperate. You should be on 20W50 oil - SAE 30 is hopeless. But it's not going to make a huge difference - you really will need to investigate the rear seal.

[aupickup]

[bmcecosse]

They sell it - so if it's not 'fit for purpose', then they should refund money and possibly even be liable for all costs to put the matter right!