Oil leakage

[Theo_NL]

Some weeks ago I experienced a huge leaking got oil after a one hour trip on the highway (60+ M/h). I must have lost more than half a liter, while I had no severe oil leakage after rebuilding the engine 10 years ago.

Today I cleaned all the oil on the underside of the engine and did a short test ride to let it get warm and show the leakage.

I found two spots: One seems to come from the seal of the carter pan at the rear side:

The other is a mystery for now. It looks like it is leaking from the cover of the clutch handle. But the clutch is working properly, there is no visible oil leakage from the hole in the clutch bell housing.

Any idea?
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[rogerowen]

Probably oil leak is coming from the rear crankshaft oil seal, and the oil on the clutch mech could be oil 'blown' back from the sump leak.

[bmcecosse]

Is oil dripping from the wiggle pin ? Does look like quite severe leak from the rear labyrinth - running into the bellhousing and obviously being splattered around by the rotation of the flywheel.. The tiny drip from the sump pan is more likely to be just a wee leak at the sump end 'gasket'. Look for pressure in the crankcase - rev the hot engine with the oil filler cap removed - is there a plume of smoke/fume? And check if the breathers are clear - and one is attached to either the carb - or the air filter.

[Theo_NL]

Bmcecosse, no there is oil leaking from the wiggle pin... (I assume you mean the pin in the hole at the bottom of the clutch housing). That makes it strange for me to believe it is the rear labyrinth. But I will check if the breathers are clear first.

[MarkyB]

The rear seal of the sump is certainly leaking a bit, how oil is getting on the clutch linkage but not coming out of the bell housing drain is a bit of a mystery, could the gearbox have been over filled when the car was jacked up or not on a level surface?

[bmcecosse]

The labyrinth must be leaking - there is a LOT of oil showing at the edges of the rubber bung.... The wiggle pin hole must surely be blocked - or has it all run away earlier?

[Theo_NL]

The test ride I made was not long enough to let the oil drop from the wiggle pin. When I looked some days later, it was dropping oil.

Took the engine out. Oil all over in the clutch housing (clutch was clean, great design!).


Flywheel and motor plate removed.


So: oil leakage thru the rear labyrint AND oil leakage thru the sealing of the carter. Bot indicating malfunction of breathers. Right?

Confirmed by this?:

[bmcecosse]

Certainly appears to be immense pressure in the crankcase - blowing oil out every which way ! I think you should look at the pistons/rings.... and check the breathers are clear of course. The oil in the picture of the bellhousing looks to be 'sparkly' - is that metal filings - or just a trick of the light ?

[philthehill]

The engine must be creating considerable crankcase pressure to leak as it is doing.
I would agree with bmc in that it appears that compression is finding its way past the piston rings and in no small amounts either.
What breathers do you have?
1. Rocker cover vent?
2. Oil filler cap (vented/non vented)?
3. Front cam follower housing cover vent?
4. Timing chain cover vent?
5. Any other crankcase vent/crankcase depression mechanism/apparatus i.e. PCV?

[Theo_NL]

Thanks for your help!

The oil in the picture of the bellhousing looks to be 'sparkly'

The oil was 'clean' no metal parts. Must be the light here.

What breathers do you have?

1. Rocker cover vent?

Yes

2. Oil filler cap (vented/non vented)?

Non vented

3. Front cam follower housing cover vent?

Yes

4. Timing chain cover vent?

No, don't think so

5. Any other crankcase vent/crankcase depression mechanism/apparatus i.e. PCV?

No, don't think so

Pictures (now it is out, 360 degr )

[Theo_NL]

After removing the rear backplate also the space behind the oil pump cover is not clean. Is oil here normal? Or is the oil pump also leaking

[philthehill]

Theo
Thanks for posting the replies and photos.
Your engine should have adequate negative crankcase pressure/crankcase ventilation provided the pipe from the rocker cover to the air cleaner is clear and the gauze in the breather canister on the front cam follower cover is allowing pressure/fumes to pass through the gauze to the carb. There has been some recent postings regarding the breather canister gauze being totally blocked. I would check the canister to ensure that it is clear; also the breather pipe from the canister to the carb and including the drilling/hole in the carb.
If the two breathers are totally clear throughout it can only be severe piston ring blow past and you will need to remove the pistons and check the rings.
As regards oil around the oil pump - there will always be some oil/oil mist around the oil pump as there is a direct oil return passage/drilling to allow any seepage from the pump to return to the sump. With all that oil/oil mist being pushed around at the moment it is no surprise to find excess oil around the oil pump.

[bmcecosse]

No - the crankcase pressure is blowing oil/fume back up the little 'drain' hole under the oil pump. The pressure must be really bad..... had the engine been 'rebuilt' recently? It's nicely painted.....but all that glisters is not (necessarily) gold...

[kennatt]

just seen this thread,its a real shame no one suggested a compression test before the engine was removed,it would have been a good indicator as to where the fault lies.I don't thin k you have any alternative now but to strip and look at the bore/piston wear. But supose with a bit of enterprise the comps could be bench tested. Have to think about that

[Theo_NL]

Thanks all for your advice and patience with me.

bmc, to give some historical data:
Bought the car in 1998, fresh import from UK, engine running well. Minor improvements/rust removal/coating done on the car. Took engine out 2003, replaced gearbox/clutch/flywheel and replaced all sealings, but did not remove the head. Engine was running well, with hardly any oil consumption. Don't fix it if it aint broken... Only driving in summer, trips of 50 - 150 km. Did not use the Morris from 2008 to 2011 due to working abroad. Always been in dry garage. This summer made several short trips and a 3 day tour of 400km. No problem at all. Before the tour I changed the oil. As mentioned in my first post here the problem started after 100 km at 90+ km/hr highway. It had leaked about a half a liter after that trip. Added all the oil i had with me and managed to come home with ending up an oil level 6 mm UNDER min. Added oil again for the short test ride as described in the posts. Engine is running very well, good power (as far as you can expect from a 1100), no smoke from exhaust. All seems fine. No signs the engine has a problem (except the leakage of course).

Kennatt, how can I do a compression test, never done that before
And don't worry, I needed to clean the clutch housing anyway, so the engine would have been removed anyway.

For me my first step will be checking the breathers when I'm home again this weekend. Could the new oil (unknown brand) causing the blocking? What oil do you advise?

[bmcecosse]

You can do a comp test by bolting on the starter - removing all the spark plugs, and lashing the engine to something reasonably 'solid' - workbench, something like that.. Then screw the tester into one spark plug hole and crank the engine using jump leads. Repeat for each cylinder and report the readings... It would be better done 'hot' - but better now than never. http://www.ebay.co.uk/itm/UK-Profession ... 3f35bea275 The problem 'may' be 'stuck rings' - although why now.... ? It didn't overheat on the last run - did it?

[kennatt]

Yes indeed,thats how. DO IT BEFORE stripping the engine It will indicate where the crank case compression is coming from,and could save a LOT of work.Def do it now before refitting the engine,you don't want to be taking it out again,unless you like taking engines out and in and out and.....

[bmcecosse]

I suppose the thread was working round to a comp test - which I often advocate - but the OP jumped the gun and wrenched the engine out catching us all by surprise !

[Theo_NL]

Hi all,
Update with some data:
- Yes the breather canister was completely blocked, the top cover breather was open
- Compression test: 105/115/110/115
Seems low to me, but engine is cold.

Compression test setup:
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Wanted to check the labyrinth seal, but could not remove the cover:
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Bolts seems too long. Any suggestion?

Thanks for your help!

[Theo_NL]

I also checked the length of the relief valve spring. According to the manual is should be 72,63 mm. Mine is 70,4 mm. Should I buy a new one or is there another solution?