Crank seal oil leak (again)…

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philthehill
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Re: Crank seal oil leak (again)…

Post by philthehill »

Many of the after market alloy rocker covers use a standard Minor oil filler cap. I would check that yours is or is not using a standard oil filler cap before doing anything.
If you have the sealed crankcase system the oil filler cap should be the vented type.
A photo of your rocker cover with oil filler cap would be appreciated.

kevin s
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Re: Crank seal oil leak (again)…

Post by kevin s »

This is the one, it has a tiny pin hole in the cap.
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I'll dig out a minor cap and see if it fits.

Reason I'm interested is it's a brand new engine with new A+ guides and seals on the inlets but puts a small puff of oily smoke out every time it is started, wonder if not having the cover vented could be a cause. (Doesen't leak, smoke any other time or use much oil though)
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Re: Crank seal oil leak (again)…

Post by philthehill »

Thank you for posting the photo.
If you cannot fit a standard Minor vented oil filler cap you could always fit one of these to the rocker cover.
https://www.ebay.co.uk/itm/203204527194 ... BMgLP9pJVg
You would have to fit a stub to the body of the rocker cover.

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Monty-4
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Re: Crank seal oil leak (again)…

Post by Monty-4 »

I think those oil filler caps may be vented - I have one that looks the same and I can blow air through it. Worth checking.
68' 4-door Saloon, another 'Monty'.
kevin s
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Re: Crank seal oil leak (again)…

Post by kevin s »

Yes it has a tiny hole in it but I don't think it will flow anything like a vented cap, the filter Phil posted is what I was thinking of, like a Rover V8 has on the back of the non vented LH cover. I'll probably drill and tap it to take a bypass hose fitting (I have the correct tap and a spare fitting somewhere).
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Re: Crank seal oil leak (again)…

Post by ampwhu »

has anyone tried the JB Weld solution? I have the info on it if anyone is interested. It has been done by a few friends of mine and they get the occasional drip but as a whole, it's better than the 'solution' that Moss etc sell.
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Re: Crank seal oil leak (again)…

Post by philthehill »

ampwhu
I am lost - what is the solution that MOSS sell and can you enlarge on what and how the JB weld is utilised.
Phil

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Re: Crank seal oil leak (again)…

Post by ampwhu »

hello Phil, i'm on about these

https://www.moss-europe.co.uk/shop-by-m ... -kits.html

they don't work as you pointed out above.

https://www.mgexp.com/forum/mg-midget-f ... t.1992078/

if you read through the thread, it mentions the "JB weld" solution. I do have a step by step guide on how to do it.
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Re: Crank seal oil leak (again)…

Post by philthehill »

Thanks for the explanation.
I would not fit a rear seal kit to the 'A' Series other than the MED kit unless the flywheel mount flange outer face is surface ground - see my post below.
I have read the instructions contained in the second link and to me it is not an easy option. Too much fiddling and faffing about and no guarantee of success.
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Last edited by philthehill on Sat Jun 11, 2022 8:45 pm, edited 1 time in total.

ampwhu
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Re: Crank seal oil leak (again)…

Post by ampwhu »

fair point. but other than going to MED, who will only do a 1275 in line block, there aren't any other options.

Try the JB weld method. It does improve the rear drip. A few have tried it with success. Granted, it needs to be done when rebuilding a new engine.
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Re: Crank seal oil leak (again)…

Post by philthehill »

As regards fitting a lip seal to the 948cc & 1098cc engines - if the outer face of the crankshaft flywheel mounting flange was surface ground there would be a much better chance of the lip seal working. The outer face of the flange is not machined just rough finished which is the downfall of the lip seal. If the outer face is not absolutely smooth the lip of the seal will be easily torn leading to seal failure. Very little if any metal has to be removed from the flange to make it smooth - so to me having the circumference of the flange surface ground, the spacer between the crankshaft and flywheel installed and the lip seal kit fitted would make more sense and give a better chance of curing leakage from the rear of the crankshaft.

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Re: Crank seal oil leak (again)…

Post by ampwhu »

i agree with that. However, you know what your doing and have a lathe. Average Joe Public can have ago at the JB Weld method without any machining equipment. I think this method is aimed at the garden shed engine builder.
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Re: Crank seal oil leak (again)…

Post by Sleeper »

ampwhu wrote: Sat Jun 11, 2022 6:50 pm has anyone tried the JB Weld solution? I have the info on it if anyone is interested. It has been done by a few friends of mine and they get the occasional drip but as a whole, it's better than the 'solution' that Moss etc sell.
Yes, I have the JBWeld along with the lipseal from Moss , have not run the engine yet so can't give any feedback...

Maybe as belt and braces and buttons , will also fit the drip-tray mod.

John ;-)
oliver90owner
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Re: Crank seal oil leak (again)…

Post by oliver90owner »

Phil is spot on re surface grinding. The issue can be both surface finish and concentricity, but hopefully only the former…
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