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Oil Leaks

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Oil Leaks

I took the air filter cover off my 1.1 E's lump today and there's some oil in there. It was covering about 10% of the inner area of the element  around the orange oval thing and the white tube area.
Any idea what causes this? does it come up thru the carb or something?

Also, would it be a good idea to spray the carb with carb cleaner before i put the new filter in? - obviously i'll clean up all the oil too.

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Also, there were a few drops of oil on the ground under the engine this morning, i did go for quite a 'spirited' drive last night and made the little lump work a bit harder than its probably used to. But what are the common oil leaks on these engines, and are any of them easily fixable?

cheers :D

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I found this on another site, does this sound like the culprit. If so how do you fit it? (i don't have any mayonnaise, phew)


Q: I have oil in the air filter housing. What is wrong?

A: Your oil separator is perished. On 1.1/1.3 engines, this is on the back of the block, and must be changed. On 1.6/1.8 engines, this is part of the rocker cover, and the whole cover must be changed. If you have a 'mayonnaise' type mixture in the air filter housing rather than oil, then the chances are that your head gasket also needs replacing.

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I would say almost definitely the answer, if the oil separator's decintigrated, then it will allow oil up the breather pipe and into the air filter housing, particulalry if you drive the car hard.

This had happened on my 1300 golf I owned about 5 years ago.  I never actually replaced it, as I wasn't interested in keeping the car long term at that time.

No idea what the common oil leaks on that particular engine are, but normal culprets on most cars are sump gasget perished, sump nut not sealing or rocker cover gasget perished (then oil drips down side of engine causing a right mess)  Also the seal around the oil filter if it not tightened properly. There are loads of other places, but these are probably the most common.

Basically see where abouts the oil is dripping from, then have a good look around that part of the engine. Most oil leaks are in my experience simple to locate, and usually fairly easy to solve.

1983 White cabriolet GTi - daily driver now with new cam belt. :-)
1992 Mitsubishi Delica Chamonix 2.5 Turbo Diesel - currently broken.

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Great, thanks for the info ! i'll grab the seperator on me way home if its cheapish - and they have em.

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Not 100% sure but I think only MK11s had a plastic oil separator :?: , MK1s simply had a rubber hose from the semi circular sheet metal bulb at the back of the block up to the filter. If any thing the hose collapses or disintegrates or the  metal bulb clogs up meaning no oil/vapour can get out leading to leaks elsewhere due to back pressure. :?  If there?s loads of oil coming up it probably due to high crankcase pressure due to a worn engine. Try changing the oil and just clean out the air filter occasionally. Make sure you can get a metal bulb back in before you hammer the old one out. It?s a pig of a job with the engine out and on the floor???almost impossible sandwiched up the bulkhead with the exhaust preheat pipe in the way. :x

As I say unless its throwing gallons out I?d leave well alone, even new engines would have had some oil vapour condensing in the air filter.

1983 Mars Red 1.8 Golf GTI
1987 Alpine White 1.8 Clipper Cabriolet

The trouble with doing nothing is that you never know when you are finished.

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right ok, i'll change the oil then and hope that the oil seperator is ok.

What exactly does the oil seperator do? i dont understand why it would send oil up into the air intake - is it a pressure release mechanism or something?

I'm afraid i have a habit of driving cars quite hard, is there anything i can do to prepare the car for this (other than lube and filter changes), or should i just calm down and pretend miss daisy's in the back seat?

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Oil in the air filter housing can be a sign of piston ring wear. Excessive wear causes crankcase fumes to be forced out past the breather and into the air filter. If the air filter then gets clogged it in turn causes a rich mixture which can lead to excess fuel washing oil from the cylinder bores making the problem worse.

I would temporarily remove the breather hose from the air filter housing until you find the cause.

As well as normal oil leaks from the valve cover and oil cap, the small block engines suffer from an oil leak from the head gasket at the front left hand corner above the alternator. The reason for this is that the oil gallery from the pump sits outside the ring of cylinder head bolts rather than inside. If any oil leaks onto the alternator it can quickly ruin it. Best solution is to fit new gasket on a skimmed head with special gasket sealer.

Cheers
Rajan

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In simple terms the oil separator separates oil from the air. Normally it's a dense metal gause of some sort. The oil gets trapped in the gause, and falls back into the engine crank case, the fumes from the crankcase carry on to the air filter housing, where they get taken back into the engine.  It's almost a form of recycling!!

1983 White cabriolet GTi - daily driver now with new cam belt. :-)
1992 Mitsubishi Delica Chamonix 2.5 Turbo Diesel - currently broken.

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cheers for the explanation maniac.

Rajan, removing the breather hose from the air filter housing is a safe thing to do then? can i just leave it like that or will it cause damage.

Sounds like the oil sender replacement is a very tricky task. Not sure i can do that myself. And i wasnt planning on re-skimming and fitting a new head gasket - unless you can assure me its an idiot proof task !

I'll see how i get on with an oil and filter change first.
cheers again.

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You need to find the cause asap, removing the breather is only a temporary measure especially if it is a lot of oil. Is there significant oil consumption?

You need to check both the oil separator and breather hose as described plus do a compression check for piston ring wear.

You also need to find out where the oil leaks are coming from, otherwise you may have to take the head off twice to fix all your problems.

Find where all the problems are coming from before you fix them one at a time and spend money on oil, filters and stuff.

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Not sure on oil consumption yet. filled to exactly 1/2 way between the dots on the dipstick yesterday, will check it regularly.
Checked the air filter at lunchtime, as i'd cleaned it yesterday. There was a tiny bit in there, hardly any, and i guess i did about 30-40 miles since i cleaned it, some at around 85mph.
Would it be high speed or acceleration, or just a hot engine or too much, too little oil in it that makes more oil shoot up there?

I will look into fixing it asap, i want to spend almost as little as possible though. Will this oil problem mean the lump will die if i don't sort it right away, or can i get away with regular air filter cleaning for a while?

Oh, and i  put 4 or 5 squirts of carb cleaner into the carb with it running too. there was a little gunk in it but not much. Its a weber 31 pic from GSF a year or two ago.

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Greg, my first car was a 1272cc GF engine (same as yours, but with bigger pistons/bores, and a 34mm carb instead of the 31 you have).

Here's my experience with oil in the air filter housing (may repeat some of what was said above).

The reason you have any oil in the air filter area is that some of the compression pressure is getting past the piston rings, into the sump area (how many miles are on the engine?)
The pressure would build up here and blow all of the gaskets on the engine, except that VW (and all makers) have put a breather system on the engine, which feeds the high pressure back up and into the air intake (where the pressure is low from the pistons sucking air into the engine). The reason that they don't just allow the high-pressure fumes to vent into the air is that they contain a high level of partly-burnt fuel which, as such, are very bad for the environment. EU and US legislation means that it would actually be illegal to sell cars without this EGR (exhaust gas recirculation) feature. Also, if the system is disabled (pipes removed) you will fail the MOT.
From what you say, the problem isn't too bad yet - if the filter was soaked in oil, and there were small puddles in the plastic filter housing, then you would have a serious problem.
It won't ruin the engine if you don't do anything with it soon - you can use the level of oil in the air filter housing as a gauge to how worn the engine is. It's tempting to drive fast, when you're young (God, I sound old!), but if you do drive it hard, it will need sorting sooner than if you "drive Miss Daisy", so you decide…
Changing the hemispherical breather on the back of the engine won't cure the oil in the air filter issue, because that's due to (normal-for-age) bore/piston-ring wear, but you should check that the breather isn't blocked with crud, because if it is, the back-pressure will blow the gaskets as mentioned, and you will have oil leaks from almost everywhere on the engine.

The issue with the head gasket leaking oil out over the alternator is common enough, but you don't need to do anything with it unless there is actually wetness going in through the vents in the casing of the alternator body, and onto the windings. I ran mine with some actual oily wetness on the engine itself, a damp, dusty area on the alternator bracket, and almost no oil marks on the alternator itself, and there was no problems.

Above all, keep an eye on the dipstick oil consumption, and on staining in the air filter housing, and near the alternator, but other than that, enjoy your car…  :lol:

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Do a compression check, monitor oil consumption and check air filter housing. Only then can you decide on the condition of the engine and the best/cheapest way to fix any problems.

Cheers
Rajan

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Also I don't think how you use the engine will make much difference to oil consumption. If the cooling system is working OK, the engine will remain within operation conditions anyway.

Cheers
Rajan

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Type17 said

you should check that the breather isn't blocked with crud, because if it is, the back-pressure will blow the gaskets as mentioned, and you will have oil leaks from almost everywhere on the engine.

Wow, thanks for the reply Type17, its very much appreciated. Excellent explanation of a problem i didnt really understand.
If i could ask yet another question, how would i check the breather?

DB - I will keep my eye on levels etc, cheers.

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With the engine off, you should be able to blow down the breather tube (after removing the air filter housing - two bolts and the spring at the rear). Blow really hard, with the oil filler cap off (so there's somewhere for your breath to go). If there's any resistance at all, there too much resistance for the engine (which can "breathe" a lot more air per second than you!), and you need a new breather which, as mentioned above is a pig to fit when the engine is still in the car.

Also you can start the car with the air filter removed (fine for a few mins), to see if fumes are pulsing out of the breather, but you can't tell if it's partly blocked by this method, as you may be looking at (eg:) only 5% of the fumes (ie: the breather is blocked by 95%), so this method only works if it's 100% blocked.

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I have had the airbox open and noticed a few fumes coming out thru the tube, so i guess its not 100% blocked like you say. I'll try to clear it a bit more by blowing, and will re-check to see if oil is still getting up there. Thanks again mate.

Off to GSF for some GTi arches & a new fuel cap today :) (i get a 10% discout which is handy).

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I' had a good look around the airbox, and the tube in question from the breather to the air box housing has a split in it about halfway up. Its not too oily though, but there's an inch long split straight down it. I guess i should replace, then try blowing down it to check for resistance ?

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Greg said

I' had a good look around the airbox, and the tube in question from the breather to the air box housing has a split in it about halfway up. Its not too oily though, but there's an inch long split straight down it. I guess i should replace, then try blowing down it to check for resistance ?

You need a new hose, but see if you can get one from a Polo or Mk1 Golf at the breakers (Don't think that I'm a cheapskate, always mentioning breakers - I don't mind buying new parts when required, but this is one of those parts that will cost a packet from VAG, and will be easy to find used, and where a new one will have no advantage over an ok second-hand one)
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