Crankshaft oil eaks

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Crankshaft oil eaks

Postby bigGandhisMK1 » Sat Nov 12, 2016 9:36 pm

Mk1 1993 Eunos - engine and box out, complete engine rebuild on reconditioned short engine, new water pump, new oil pump. Engine back in but oil leak appeared at front crankshaft area /sump interface. Engine back out, sump off, new half seals again and rescaled with RTV sealant. Engine back in, runs like a Swiss watch but oil leak still there, searched for external leaks but found nothing. Is there anything that could be at fault which is creating excess sump pressure and forcing oil out through the seal, oil seepage is tiny at tick over but ramps up when revved. Any ideas folks!
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Re: Crankshaft oil eaks

Postby drumtochty » Sat Nov 12, 2016 10:09 pm

If the oil pressure relief valve is stuck closed that could be it.

I assume you changed the front crank oil seal.

The sump has not been overfilled how much oil did you put in.

Are the oil breathers on the topside of the engine working or blocked.
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Re: Crankshaft oil eaks

Postby bigGandhisMK1 » Sat Nov 12, 2016 10:25 pm

Hi, the recon engine was fitted with all new seals on both crankshaft and cam shafts, every seal is new. I also ran the engine with all the timing belt covers off and did not find any leaks running down from above. Oil level is about 75% on the dipstick, as I was waiting to cure the leak before fully topping up. I will check the breathers asap. Oil pressure gauge showing expected levels and not high ones hence its a mystery.
Did think the oil pressure relief valve was sticking but it is a new unit hence low down on the suspicious list
As you can imagine I do not want to remove the engine for the 3rd time
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Re: Crankshaft oil eaks

Postby drumtochty » Sun Nov 13, 2016 12:24 am

Deep scratch on the crankshaft as it comes through the front of the block where the seal sits.
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Re: Crankshaft oil eaks

Postby bigGandhisMK1 » Sun Nov 13, 2016 12:40 pm

I will be doing more checks today and if I come up with anything of note I will let you all know. It's up on blocks so it's a mission with the torch and an eyeball on a stick !
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Re: Crankshaft oil eaks

Postby mgrays » Wed Nov 16, 2016 5:27 pm

When replacing seals you should use 1000 wet n dry with WD40 to polish the seal running surface on the crank. Old oil will have left a varnish and may even have grooved the steel surface. If there is still a groove after the polishing then do not drive seal in so far or drive in too far so as to move the seal lip away from the groove. TBH this is not likely to be your issue but before I started doing this 20 odd years ago .. my replacement seals always weeped more than I would like, now they are always tight. I have seen second hand engines that were sold as good .. and then found they were accident damaged due to the crash that wrote the car off.. so it might be a damaged/cracked front cover; a bodge is get engine hot, clean with petrol around the leak and then plaster over something like plastic padding etc and leave it to harden. At least 3 engines of mine were fixed of oil leaks from hard to reach gaskets/impact damage like this. Not the best and all over 20 years ago now!
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Re: Crankshaft oil eaks

Postby bigGandhisMK1 » Fri Nov 18, 2016 9:08 pm

After much poking about and eventually running the engine without the plastic timing covers, pulleys and belts, the crankshaft front seal looks like the culprit. This is a new oil pump and a reground crank so this should not have leaked, however new seal has arrived and hopefully will get changed out this weekend. Will double check crank for grooves or scratches. Fingers crossed for half decent weather as its on the drive on breeze blocks.
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Re: Crankshaft oil leaks

Postby bigGandhisMK1 » Fri Dec 02, 2016 8:25 pm

Hi All,

Well finally got the crankshaft oil seal changed out, used a home made tool to remove it as opposed to using the screw method and it worked a treat. No gouges, scratches on the surfaces so straight swop. All back together now and the moment of truth showed no oil leaks - result! Guess I must have nipped it when installing the new oil pump, just goes to show you need the touch of a midwife for these things.
I can now carry on with my other list of jobs now that's sorted, thanks for all the comments, no doubt I will have other queries about other things down the line.
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All good under the hood !
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Re: Crankshaft oil eaks

Postby IanH » Fri Dec 02, 2016 9:44 pm

Thanks for sharing the fix, it's always good to see the outcome.
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Re: Crankshaft oil eaks

Postby drumtochty » Sat Dec 03, 2016 11:51 am

Lookin Good!
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Re: Crankshaft oil eaks

Postby OldSpice » Wed Dec 07, 2016 11:14 am

That's Show quality presentation. I think I'd pop the bonnet at every fuel-up to show it off. :mrgreen:
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Re: Crankshaft oil eaks

Postby bigGandhisMK1 » Wed Dec 07, 2016 4:47 pm

Hi, thanks for the comments, I cleaned up all the parts whilst the engine was out and splashed some paint around in the engine bay after jet washing it. The rocker cover was rubbed down and powder coated in Subaru gold, it makes all the difference, £70 well spent I think. The induction parts were bought separatly on the net and came to under £50 and I made up the bracketry myself . It's amazing what you can do once you have the time after being made redundant ha! Back working now so all is good
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