AAZ Vanagon losing oil

[RockOcean]

Hello all, it has been almost 4 years since my "AAZ rebuild (broke down in Maine)" post where I rebuilt my motor thanks to the help of you all. I have put about 90,000 miles on the motor since then.

About 6 months after the rebuild I did a compression check and got 500psi on all but one cylinder was 490psi.  I was having to put in a half quart of oil every 1500 miles. About a year ago I started getting a good few drops of oil every time I parked. I then had to put a half quart of oil in every 800 miles. The leak turned out to be a combo of rear main seal, but mostly it was leaking from the oil galley plug.

Before I left home one month ago I fixed all the oil leaks. The only noticeable one was from the oil cap that wasn't leaking that bad. I have driven over 2000 mile thus far with not a single drop of oil hitting the ground. But all of a sudden I was having to put a half quart in every 600 miles, then 400 miles, then 300 miles.. I have a catch can setup that drains back into the block, and have had this setup since my rebuild. I checked the inter-cooler piping and there was no pooling of oil. I took off the hose that goes into the intake from the catch can and put it into a test can to see if that is where the oil was going. I drove like that for about 100 miles with hardly any oil in the can.

The motor fires right up and has no signs of performance loss. I then decided to take the hose directly from the pcv valve and put that in the test can to see if any oil comes out when bypassing the catch can. I sealed the catch can openings simply by tie wrapping a plastic bag around them so dirt would not get in it while driving. Once again, no oil in the test can. But, oil shot out of the catch can that I sealed off. I am thinking maybe the catch can drain got clogged up and the crankcase pressure cleared it and shot the oil out that was in it.

There are no signs of any blue smoke while driving. Only when starting the van cold at high elevations does it puff a little white/blue smoke. I am waiting for some injector seal plates so I can run a compression check. Other then that I don't know what else to do. Is it possible for my valve cover/ oil cap to be leaking down onto the exhaust manifold and then burning off, hence not showing any drops of oil when parking? . I left Florida a month ago and am currently in Utah with plans to head up to Alaska. Any help would be greatly appreciated.

Thanks, Ryan


CatchCan by RockOcean.com, on Flickr

OilCap by RockOcean.com, on Flickr

IntakeOil by RockOcean.com, on Flickr




 

[vanbcguy]

3 cylinders at 500 and one at 490 is pretty damn good actually.  A 10 PSI difference between cylinders is nothing to worry about at all.  500 PSI is great compression too.  You definitely don't have any issues with ring seal!

So you're still having to add a quart every 300 miles?  I see your valve cover is pretty wet in that picture; the severe tilt of the engine in a Vanagon will definitely shed quite a bit of oil from a leaky valve cover.

Also, in the picture below it looks like your oil cap has a pretty poor seal?  Doesn't appear to be sitting flat on the valve cover?

[RockOcean]

Im now losing a half quart every 100 miles! Any suggestions? Im currently in Grand Priarie, AB (Canada) on my way up to Alaska.

[air-cooled or diesel]

ive seen a few times where a leak should seem obvious but can be hard to detect. 1st i might use a big piece of cardboard covering from wheel to wheel and front to back(motor area, etc) and check, other than that it has to be going somewhere, most likely a leak, joint or gasket. get motor nice and hot, park it on cardboard, maybe let idle for a while and trace for oil leaks. either than that check breather vent for excessive oil or smoke, would end up going down intake, so it doesnt sound like your problem, as it would runaway if what your saying was going there.
check oil pan and under timing cover crank flange, can be hard to see, (im shaft seals?)

[RockOcean]

Thanks for the quick reply. There are no leaks on the motor besides from the oil filler cap, and that leak is very minimal.

Since my last post a couple of hours ago I went to the local diesel specialist. I got super lucky and the nicest mechanic came out to check it out. Right away he took off the oil filler cap and let it bounce up and down in between the engine and his fingers. "Its blow by" he said. Then he looked at my cone filter and said "You gotta put some oil on that filter, you probably got some dust in your engine and it's worn your rings to cause the excessive blow by." He explained everything so spot on. Then he recommended using a 5w-50 oil and adding some Lucas oil additive. Saying that should get me up to Alaska and back.

So I got some 5w-50 Castrol . I am going to hold off on the Lucas oil for now and see if the 5w-50 works better.

[air-cooled or diesel]

one thing im working on you can do. until you 'fix' the blow-by problem. separate the vents, you may need other vents(crankcase). although new vents require you to drill(clean) and have vent 'nipple(s)'. was very common on T1 bugs and like. you had lots of possibilities. like alt stands with multiple vents available. in separating vents and blocking off intake you now start with more venting, i was thinking an oil cap that fits yours with venting in it. get a vent box, for you with the oil looking like its coming up thru the cc venting youll need to set up something, as it ends up you can recover the oil coming up to a vent box. the more venting you have, until you fix, the less chance oil will be pushed up vents, and will give you a chance. i doubt pepboys has anything like this anymore, thats sometime ago, possibly napa can order something -special. or an independent shop, possibly a speed shop will still carry something like this.
id start with separating the (2?)vents, blocking off(open ports), and running vents into a vent box. a box may start to fill with oil, but on 1 side it wont go down the intake.

[air-cooled or diesel]

id start with separating the (2?)vents, blocking off(open ports), and running vents into a vent box. 

on some further thought, and some specific explain,, such as, the lower cc hose you can use a sleeve, prob can find something that fits in like a plumbing shop(can even perhaps have threads), or such as a brass(or similar) connector, that slips into lower hose, then run 1 hose to vent box, clamps. the valve cover vent has 2 openings, run both of these now to vent box, find extra venting, such as from cap would be easiest, even trying to get 2 vents coming from top of cap, run to vent box, make sure box can breathe to outside. when you get done (fix it), the only thing youll really need at this point is a new oil cap.

[RabbitJockey]

i wouldnt give that blow by test too much weight.... they all have some amount of blow by, a compression test will tell you much more than just observing how much the cap rattled around(they will all do that.)  what is the history and condition of the turbo?

[RockOcean]

Thanks, I have been thinking about adding an extra vent. My catch can drains the oil back into the motor.

I put the new 5w-50 oil in and drove 450 miles before having to put another half quart of oil. That second half quart only lasted 250 miles. When I changed the oil it seemed super thin. Is there any chance that diesel is getting past the rings and in the oil making it thinner? The oil does not smell like diesel tho. I reluctantly put in a half quart of the Lucas oil to see if that helps. We made it up to Fairbanks, Ak and are now heading South to Northern California over the next month.

The turbo is a stock K03 with about 90,000 miles on it. Boost and performance seem the same as it was when new. It's not blowing out any oil, or abnormal smoke. Which leads me to believe the seals are ok.

[libbydiesel]

I bypass the catch can AND block the drain to the block.  Reconnect the stock puck to the intake and drive it for a while like that for a while and measure how much oil is consumed.  If the oil consumption is reduced, you know it is an issue with the catch can system, namely allowing it to suck oil up the drain and into the intake. 

[RabbitJockey]

yeah also, if you're running that, i would think the hose going to the intake should be on top and the hose coming from the puck should be on the bottom, but i don't know whats inside of the can

[RockOcean]

Yes I have thought of deleting the catch can and drain to see if it is the culprit. I just need to find the bolt to put in the drain hole into the block. Will let you know how that works out. Thanks

[RockOcean]

I switched the hoses so the top one does go to the intake shortly after my first post. It doesn't seem to make much difference. But I will contact the manufacture and see what they say. Thanks

[RockOcean]

Today I ran a few tests. First was running the catch can hose from the top outlet into a catch bottle for 20 miles on the way to the auto parts store. No oil in the bottle. Then I plugged the crank case hole for the catch can oil drain. Then deleted the catch can system returning it back to stock. Except I plugged the intake hole and routed it to a catch bottle in case there was excessive oil from blow by coming thru. I drove about 10 miles and sure enough there was about 1/20th of a quart of oil in the bottle. So  I assume it is definitely bad rings? Could it just be the oil rings that are bad. Hence there no lack of performance, or hard starting?

I ended up hooking the catch can and oil drain drain back up. But this time I kept the intake hole plugged and ran the top cc hose to a bottle that I mounted where the rear mud flap would be. I am thinking that more oil might drain back into the crankcase of there is no suction from the intake on the other side. I mounted the bottle at the mudflap in order to keep fumes from creeping thru the engine lid into the van.

I might have an  opportunity at some garage space in Anchorage to change the rings. Anyone know of someone around there that maybe able to help out? Another plan is to take the ferry from the there to Bellingham. Leaving me with with only 700 miles to my final destination. Thanks for all your help!

[libbydiesel]

You may be relegated to rings at this point.  Oil control rings might account for oil being burned in the cylinders directly but they do not account for excessive oil usage from the crank vent.