PDA

View Full Version : Oil leak, high miles...



DND
10-24-2018, 11:45 AM
My 2001 A4 1.8TQ is leaking oil badly from the valve cover gasket... (I believe).
The engine is old (180K+ miles), it has burned oil for years but the "new" leak is "worse".
Starting from the front my compression numbers are:
120+
100 - 110 (tested twice, got 100 the first time, got 110 the second)
120+
120+

I'm going to replace the valve cover gaskets and hope I can keep driving the car without doing a rebuild but I'm wondering if I should try to replace the valve stem seals while the cover is off?
I don't want to remove the head if I don't have to... (I'm not sure why I'm so afraid of doing that).

I still like the car, and have sunk too much money into over the years, but its market value is so low now that serious work (unless I make time and space to do it myself) isn't cost effective...
I'm not sure what to do with it if I can't get it running cheaply and easily since my wife forbids me to part it out. ;)

Thanks in advance for your advice.

DND
10-24-2018, 05:37 PM
Don't be shy, any advice is appreciated. [wrench][:)]

WagonGuy
10-24-2018, 07:21 PM
If market value was the only consideration then none of us would be fixing up these cars, we do it because we like to drive them, and some of us even like working on them :) I picked up my 2001 for $800 and have more in it than I will admit in it now, but I don't regret any of it; a newer car doesn't have the same feel as the B5.
You could fix the oil leaks (be sure to change the timing chain tensioner seal and half moon plug) and wait until the timing belt is due and then replace the valve seals. I would not try it with the head on the engine. The valve keepers are a bit of a pain. With new seals if your engine does not have sludge or been abused, you should be able to get at least another 100k miles out of it. I have 200k on mine with new seals and rings and it runs like new, does not use a drop of oil.

Turbo_B5
10-24-2018, 08:56 PM
buddy its fucked. get a used engine.

warrenzo
10-24-2018, 09:47 PM
I agree with wagonguy, you'll spend more time than it's worth replacing valve seals with the head on. Taking the head off is easy, but you have to dish out for a hg and head bolts. Valve cover gasket and cam seals should be quick and cheap enough, and if worst case scenario it doesn't fix anything, you haven't spent too much at it.

Davdraco1
10-25-2018, 07:31 AM
What should compression numbers be?

RENOxDECEPTION
10-25-2018, 07:55 AM
I mean, there are basically 3 places your car could be burning oil, turbo, valve seals, or piston rings.

How do you know your turbo isn't the culprit? It's the easiest fix.

It is absolutely possible to change the valve seals with the cylinder head on, some people stuff rope into the cylinder at top dead center and knock the valve keepers out, other people use compressed air (I don't trust that method).

One note is probably to block off every single possible hole that a valve keeper could fall down with shop towels because if one drops into your crank case, you're screwed.

I've never changed them with the head on, but I could see how it could be a major pain in the ass, and by the time you have the cams out you've already reached a point where you might as well just pull the head and be done with it.


If you want to attempt it, do yourself a favor and buy one of those nice valve spring compressors that bolts to the cylinder head like this (https://www.handsontools.com/Baum-Tools-3362-VWAudi-Valve-Spring-Compressor_p_155375.html?gclid=Cj0KCQjw08XeBRC0ARI sAP_gaQByMcSpuH1ry8Ui1VvxXTUphh76ZJqFxzvONRQ3Bj24-uo_NsyxN5saApNuEALw_wcB)

and also a set of some nice long skinny valve seal pliers/installation tools.


But, with that mileage, be prepared for it all to be in vain as it could be your turbo, or piston rings also.

You can find cheap, low mileage engines, also turbos.

DND
10-25-2018, 10:26 AM
What should compression numbers be?

According to my manual the compression numbers should be in the range of 145 to 183 (I think) with 100 being replacement time.

DND
10-25-2018, 10:31 AM
I've got oil on and around the valve cover, three of the four coils have crud on them, the worst one is also the worst compression cylinder. I could be wrong but I'm thinking the only way for oil to get there is from the valve cover gasket.
As for the turbo, I don't know how healthy it is, I don't think it spools nearly as fast as it used to. K03S, I think it's supposed to fully spool by 2500 but I think it's over 3000 now.

DND
10-26-2018, 10:21 AM
Does anyone think I should bother with the really expensive ARP head bolts?
I'm not planning on taking the head off enough times to justify $150 vs. $20 or less for regular stretch bolts but if I'm missing something please let me know.

DND
10-26-2018, 10:25 AM
Also, any expert opinions of gasket kits?
There is this one (https://www.ebay.com/itm/OEM-Audi-A4-TT-1-8T-VW-Passat-Turbo-Cylinder-Head-Gasket-Set-Bolts-2000-2006/253897007654?_trkparms=aid%3D555018%26algo%3DPL.SI M%26ao%3D1%26asc%3D20131003132420%26meid%3Dccaf668 072524ce183ac31371346e71c%26pid%3D100005%26rk%3D4% 26rkt%3D4%26sd%3D152577383104%26itm%3D253897007654&_trksid=p2047675.c100005.m1851) that is basically the same stuff that ECS Tuning sells.
Or a way cheaper kit (https://www.ebay.com/itm/97-06-Audi-A4-TT-Volkswagen-Passat-1-8L-Turbo-DOHC-Head-Gasket-Kit-AEB-AWM/300871427863?hash=item460d55a717:g:UpsAAMXQTghRNom E:sc:FedExHomeDelivery!98077!US!-1)...

DND
10-26-2018, 10:38 AM
buddy its fucked. get a used engine.

I looked into that, it seems they cost more than the car now. [;)]

Turbo_B5
10-26-2018, 02:25 PM
Not really An engine is $2-500.


Sent from my iPhone using Tapatalk

Turbo_B5
10-26-2018, 02:29 PM
At this point you are looking at a full engine rebuild, rings, valve guides possibly, machine work. If you don’t think you can do rings yourself just get a used engine a lot less work. My “quick” rebuild on my tdi is currently at like 5 weeks.


Sent from my iPhone using Tapatalk

DND
10-29-2018, 04:18 PM
Not really An engine is $2-500.

Clearly I'm looking in the wrong places then...

DND
11-29-2018, 12:56 PM
I did some searches on car-part.com and partshotlines.com and the engines that are no better than mine start at $500 and go up.
The ones that aren't hundreds of miles away from me start $950 and go up.
Anything with lower mileage and better compression, anywhere in North America, is typically well over $1000.
I did find one "$5" engine core that requires complete rebuild and is missing parts with 210K+ miles on it but that's just pointless as I could do the same rebuild to the engine I've already got and not have to pay hundreds in shipping for an incomplete block.

Wooshy
11-29-2018, 06:01 PM
Hey, i thought i had the same type of leak check your oil sending unit, the damn thing dumps oil if it get a pin hole in it

mobildetroit
12-03-2018, 02:38 PM
Put a new valve cover gasket on it (easy and cheap to change) then dump 10oz of Seafoam in the engine with a fresh oil change. Do this for about three oil changes (3000 miles). Make sure you use a 10w30 synthetic oil, any brand. Audi engines are shitty and coke up easily if you don't change the oil frequently enough. I'm not talking about the sludge issue from putting non synthetic oil in the engine, but even still, if you did have the wrong type of oil in the engine the seafoam thing will help over the course of three or maybe four or five oil changes. Valve cover gaskets usually don't leak though unless the cover has been off a few times, usually oil collecting at the base of the spark plugs is the tell tail sign the cover gasket is leaking. Also check oil pan and oil temp/level sensor in pan, if that seal is bad because it was removed you should replace the oring seal on it...or just get a new sensor....they are cheap. If the oil pan was replaced because you too have hit something with the oil pan and popped a hole in it, the new pan may not be sealed correctly. Audi doesn't use an oil pan gasket, they use RTV...and if there is any oil on the pan or the engine block mating surfaces it will eventually leak oil there...Best way to tell where oil is leaking on the bottom of an engine is to degrease the bottom, dry it over night, then run the engine in the drive way until it get's hot then inspect the bottom of the engine. If no new oil runs are obvious, go drive it around the block a few times (as long as it's not raining) then take it home and look again. You should see by then where it's leaking.

How do you know your engine is burning oil versus leaking it?
Those compression numbers are ok, they don't indicate you have a bad engine or that it's burning oil. As long as the compression levels are all about the same, within about 10 psi of each other then you are fine. I even think 120 or 120+ is normal for a used engine, so in my opinion those numbers are not indicators of overhaul time. I would keep running it until you have obvious oil pressure issues because of worn bearings, then do the engine rebuild/swap.
#3 is always lower then the rest because that's where the oil vapors come in to the cyl from the PCV system and the extra oil causes the rings to blow by a bit more (the idea with the seafoam is to free up coke on the piston rings and possibly help improve flow through hydraulic lifters, possibly even improve compression if the rings free up some coke and can expand fully/freely).
Also, did you do your compression check on a hot or cold engine, can be low (and that's normal) if it's cold.

The problem with Audi's are Audi' owners making assumptions about what's wrong with their car and assuming they need to rebuild their engines. The other problem with Audi's is that they are shitty cars that basically start falling apart as soon as you buy one.

Blazius
12-03-2018, 05:27 PM
Put a new valve cover gasket on it (easy and cheap to change) then dump 10oz of Seafoam in the engine with a fresh oil change. Do this for about three oil changes (3000 miles). Make sure you use a 10w30 synthetic oil, any brand. Audi engines are shitty and coke up easily if you don't change the oil frequently enough. I'm not talking about the sludge issue from putting non synthetic oil in the engine, but even still, if you did have the wrong type of oil in the engine the seafoam thing will help over the course of three or maybe four or five oil changes. Valve cover gaskets usually don't leak though unless the cover has been off a few times, usually oil collecting at the base of the spark plugs is the tell tail sign the cover gasket is leaking. Also check oil pan and oil temp/level sensor in pan, if that seal is bad because it was removed you should replace the oring seal on it...or just get a new sensor....they are cheap. If the oil pan was replaced because you too have hit something with the oil pan and popped a hole in it, the new pan may not be sealed correctly. Audi doesn't use an oil pan gasket, they use RTV...and if there is any oil on the pan or the engine block mating surfaces it will eventually leak oil there...Best way to tell where oil is leaking on the bottom of an engine is to degrease the bottom, dry it over night, then run the engine in the drive way until it get's hot then inspect the bottom of the engine. If no new oil runs are obvious, go drive it around the block a few times (as long as it's not raining) then take it home and look again. You should see by then where it's leaking.

How do you know your engine is burning oil versus leaking it?
Those compression numbers are ok, they don't indicate you have a bad engine or that it's burning oil. As long as the compression levels are all about the same, within about 10 psi of each other then you are fine. I even think 120 or 120+ is normal for a used engine, so in my opinion those numbers are not indicators of overhaul time. I would keep running it until you have obvious oil pressure issues because of worn bearings, then do the engine rebuild/swap.
#3 is always lower then the rest because that's where the oil vapors come in to the cyl from the PCV system and the extra oil causes the rings to blow by a bit more (the idea with the seafoam is to free up coke on the piston rings and possibly help improve flow through hydraulic lifters, possibly even improve compression if the rings free up some coke and can expand fully/freely).
Also, did you do your compression check on a hot or cold engine, can be low (and that's normal) if it's cold.

The problem with Audi's are Audi' owners making assumptions about what's wrong with their car and assuming they need to rebuild their engines. The other problem with Audi's is that they are shitty cars that basically start falling apart as soon as you buy one.

If that is your view on the subject, why are you on an Audi forum lol. The engine is probably the most durable part in the whole A4 B5 chassis. also I believe the recommended oil is 5W30. Compression must be min 101 PSI @ 30 C oil temp atleast. with 45 PSI permissible difference between cylinders.

DND
12-11-2018, 10:57 AM
I did the compression check on a cold engine in cool weather so now you've got me curious what it would be when warmer.
I've done checks for oil leaks in the past and I don't think anything is coming from the pan but oil has been consumed for years without any ever showing up in my garage or driveway.
The oil on top is a recent development, I need to check again if replacing my worn out filler cap gasket had any effect since I think it had been leaking for a while.

Fasterd
12-11-2018, 11:19 AM
If its high mileage Mahle makes a stock stroke 81.5 piston that you can get matched to the bore by a machine shop, then scat rods at 400 bucks you got a rotating assembly. Low compression numbers aren't a bad thing if uniform but are a good indicator of wear. after 100-150k the valvetrain should really be refreshed and if you want to reuse the block for a build its getting to that age where its time to commit or ride it to death. (Iv'e seen too many worn valve guides cause prolific consumption, especially in cars where vacuum is constant due to highway driving/low load)

the valve guide is made of softer metals, and the valve sits in at a slant, not perfectly perpendicular to the ground. This is why they knurl guides when replacing a single valve, otherwise the perfectly straight new stem can have clearance issues because the old valve had slightly contoured to the worn guide over time. These voids/ wear spots are what cause consumption, you can replace the stem seals but the lateral travel in the valve caused by guide wear will open that seal right up effectively wasting your time and money.

TBH it looks like by your garage items you have expendable income so if you like the car just rebuild the motor (if you want to go big, otherwise swap in a junkyard special)


from the 30,000 foot view the pressure test/ oil consumption tells ME that rings/valvetrain are beat (understand this is not mileage dependant, improper lubricants/service intervals/operation conditions can cause catastrophic material erosion at an impressive rate....of seconds in extreme cases)