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This isn't normal is it? - Oil in carb air intake.

Posted: 21 Apr 2009, 11:17
by conrad
Hi All

Was changing the throttle cable yesterday on my 87 1.9 DG. Had to remove the carb air intake to get near the cable at the carb and saw this.....

Image

Does this look very dirty (in an oily way) to you?

On further inspection I found this.....

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Now I'm no mechanic but I don't think that much oil is supposed to gather there? Could this have something to do with the fact that the hose that goes from the breather tower to the carb air intake has the consistency of warm blutac?

I checked the airfilter and the oil hasn't made it's way that far yet.

I am sorta hoping that this explains why the van has been feeling a little bit hesitant at about 45-55 MPH in 5th (and around the same rev range in other gears too).

Anyone got any idears as to what is causing the oil to get up there. Is it doing my engine any harm or is it a sign that the harm has already been done.

Many thanks in advance.

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 13:53
by Fritz
Oil residue probably from crankcase breather system, quite normal to find this sort of thing when buggering about with carburettor/intake, and if it isn't contaminating the air filter then it is nowt to worry about.......
A quick squirt with the old carb cleaner and she'll be as good as new.....
Regards


Fritz,,,,,,,,, :D :D

Nice photos BTW,,,,,,, :D

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 15:49
by conrad
Fritz wrote:Oil residue probably from crankcase breather system, quite normal to find this sort of thing when buggering about with carburettor/intake, and if it isn't contaminating the air filter then it is nowt to worry about.......
A quick squirt with the old carb cleaner and she'll be as good as new.....

That's a relief. Do you think that this residue could be causing the van to lightly shudder/hesitate at certain revs? With regards to the breather pipe (I think I'll replace it shortly anyway) What effect would the almost collapsed pipe have on the general running of the engine if any?

Fritz wrote:Nice photos BTW,,,,,,, :D

Thanks :D

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 16:03
by T'Onion
Take the oil tower off and pull it apart and clean it , also get a new breather to carb pipe under £20 iirc from GSF .

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 17:41
by conrad
The tower is only a few months old (cowboy mechanic let his apprentice try and top up the oil :shock: ) but I'll give it a clean anyways. Was at GSF earlier and apparently they don't do that hose anymore so I'll probably have to got to VW for that one now.

Thanks for all the help.
Conrad

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 18:01
by kevtherev

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 18:31
by conrad
kevtherev wrote:Breather pipe

:ok

Perfect, thanks kevtherev :wink: No idea why I didn't think to look there :oops: .

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 18:41
by kevtherev
conrad wrote:
kevtherev wrote:Breather pipe

:ok

Perfect, thanks kevtherev :wink: No idea why I didn't think to look there :oops: .

that's why we're here :D

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 19:34
by Mr Bean
Yes funny that! My "Plastic chimney like structure" had the top secured with polythene and an elastic band when I aquired machine. I reconed that someone had hacked it of trying to top up the oil. Bloke I got it from was a bit of a pi$$ artist so I recon he did it while in a drunken haze. :ok
Cheers
wolfie
Had to go to VW for it

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 22 Apr 2009, 20:02
by clartsonly
mine does the same, check it whilst it is running when it is cold and you may find a lot of "emulsified oil" splattering into your carbs, I think mine is condensation from the engine oil, it is okay after 20 minutes drive. I have a spring jammed into my pipe to keep it open instead of pinched but it still doesn't drain back through the breather properly.

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 23 Apr 2009, 09:00
by conrad
Well, I've cleaned the oil out of the pipe and had the carb air intake soaking in meths to remove the oil deposits. While I was there I decided to replace the little bits of fuel line that connect the thin vacuum hoses (think that's what they're for) to the carb/air filter housing etc as they were in terrible condition. One of the hoses was blocked so I cleared that with some break cleaner and stuck em back on. Seems to run loads better now but I suspect I'll need to get the timing checked etc - No idea how long that hose was blocked for but I presume it would have an effect on the fuelling - wouldn't it?

clartsonly wrote:mine does the same, check it whilst it is running when it is cold and you may find a lot of "emulsified oil" splattering into your carbs, I think mine is condensation from the engine oil, it is okay after 20 minutes drive. I have a spring jammed into my pipe to keep it open instead of pinched but it still doesn't drain back through the breather properly.

Might try that spring idea as a temp solution. Mine seems to be ok after about 5-10 mins (splutters a bit) which I'll put down to the oil splattering but mine can do the same at random times when driving. I suspect it's just all the crap in the carb so with the new/bodged breather hose and a clean carb I'm hoping this will stop.

Citizen Smith wrote:Yes funny that! My "Plastic chimney like structure" had the top secured with polythene and an elastic band when I aquired machine. I reconed that someone had hacked it of trying to top up the oil. Bloke I got it from was a bit of a pi$$ artist so I recon he did it while in a drunken haze. :ok
Cheers
wolfie
Had to go to VW for it

Me too. Bought a 2nd hand one but it was full of crud and leaked out the top just like the butchered one. Someone should print stickers for the top of that tower to warn muppet mechanics that 'oil doesn't go in here, it goes in the hole underneath the cap marked OIL'. Funny thing is, that mechanic I used is a German Vehicle Specialist!! :shock:

Pricey bit of plastic at £28 if I remember correctly, then again at nearly £25 the breather pipe is pretty damn expensive too. My vehicles are costing me a bomb this month, had an engine blow the big end bearings and trash the rest of the engine on my Saab, so that'll need replaced, and with all the stuff I've been putting off doing on the van due to cold weather it's all needing done now.

Planning to spend the next few weeks pretending to be a mechanic. :roll: After I've done the Saab engine and boosted my confidence a little I plan to drop the engine & box out of the van and clean it up a bit. Gots to do the flywheel oil seal, do the clutch if the clutch has been contaminated with oil from the leaking oil seal, replace the leaking slave cylinder, replace the bendy slave cylinder bracket, try and get to the bottom of my flashing oil pressure light, remove and flush the fresh water tank, repair/replace the 'self priming' water pump that doesn't self prime and probably replace the starting motor as it occasionally requires the gentle persuasion of a hammer to start the van. I'm sure I've forgotten another list full of 'wee jobs' but this should keep me going for a while. On top of this the rust is getting serious now :cry: so I'll probably need to get it down to my local VW restoration chaps for them to work their magic.

It never ends does it?

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 23 Apr 2009, 09:21
by AngeloEvs
Oil in the airfilter trunking/box is also a symptom of an 'elderly' engine, usually as a result of excees 'blow by' in the bores. However, under certain load conditions, the Crankcase pressure exceeds the vacuum demands in the inlet causing the problem of oil contamination along the inlet path. If a vehicle has a 'closed' PCV system (Positive Crankase Ventiliation) then a valve controls this mismatch and, if faulty, gives the same symptoms but I think the 1.9DG has an open PCV system. May be someone could confirm, never looked in the breather tower to see what's in there or whether this is a common problem with 1.9DG's. Mine does it too.

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 24 Apr 2009, 18:32
by clartsonly
I think you fellows that have had the pipe "removed" from the circuit, have got more of a problem "like me" that there is too much crankcase pressure pushing the oil through the breather. I was advised previously here to put a bottle in between to catch the oil and let the blow by gases to continue into the carb.

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 25 Apr 2009, 11:07
by conrad
AngeloEvs wrote:Oil in the airfilter trunking/box is also a symptom of an 'elderly' engine, usually as a result of excees 'blow by' in the bores. However, under certain load conditions, the Crankcase pressure exceeds the vacuum demands in the inlet causing the problem of oil contamination along the inlet path.

So am I correct in thinking this is the result of worn piston rings or am I talking out of something I should be sitting on? The engine is coming out in a few weeks so that might be a good time to change 'em?

AngeloEvs wrote:If a vehicle has a 'closed' PCV system (Positive Crankase Ventiliation) then a valve controls this mismatch and, if faulty, gives the same symptoms but I think the 1.9DG has an open PCV system. May be someone could confirm, never looked in the breather tower to see what's in there or whether this is a common problem with 1.9DG's. Mine does it too.

Can anyone confirm if the DG engine has a closed PCV system? Can't seem to find any mention of it in the Haynes or the Pocket Mechanic manuals.....

clartsonly wrote:I think you fellows that have had the pipe "removed" from the circuit, have got more of a problem "like me" that there is too much crankcase pressure pushing the oil through the breather. I was advised previously here to put a bottle in between to catch the oil and let the blow by gases to continue into the carb.

In the meantime I'm going to try the bottle method to see what crap is actually coming out of the breather.

Re: This isn't normal is it? - Oil in carb air intake.

Posted: 25 Apr 2009, 14:02
by AngeloEvs
No, as far as I can see its 'open', I took T'Onions advice and lifted the breather to look in it and give it a good clean, there is just a baffle. As far as I know on an open PCV system fresh clean air should enter from somewhere, usually from the oil filler cap (on most open PCV cars that I have owned) but there ain't one on a 1.9DG. It seems as though oil does get into the inlet on these (and it is normal) but it all depends on how much and wether this is due to the pressure differntial between the inlet and crankcase pressure under certain driving conditions. I don't know of anyone who has removed the breather pipe and venting to air, pretty sure that would be a contentious mod and I would have spotted that one as a thread. I check mine regularly and give it a good clean every so often but have considered fitting an in-line filter. My engine has covered 95K now so I guess its getting on a bit. See what others say as to wether this is normal. I have carried out Mocki's tip and replaced the breather pipe with flexible conduit and made it longer (hopefully catch some of the crud)......excellent tip that one and looks the Biz!
:ok