emeryz28

I just replaced the head gaskets and had the dealer install a factory oil pump. I also installed the Jegs short polished aluminum valve covers. Now, oil is coming out my dipstick at the top.

I replaced the PCV valve on the driver's side and checked the vent valve that goes to the throttle body intake on the passenger side. There are no obstructions.

I installed the passenger side valve cover with the vent hole towards the back firewall because I recall I was having trouble getting the cover to fit on with the hole towards the front like the original valve cover. Also, my stock oil filler cap would not fit (to small) so I had to get a chrome cap with a rubber stopper base. I'm not sure if my original cap had a vent but the chrome cap does not.

Would either the vent hole in back or the new cap cause the problem I am experiencing?

Thanks.

pound

iTrader: (7)

Sounds like you have some blow by and the crank case is getting pressurized which forces oil out of the dipstick tube. If your signature is accurate and the motor is original with 200,000 miles I would not be surprised that the rings are worn. You can do a leak down test or compression test to confirm this.

emeryz28

I just had the dealer do a compression test and it was okay.

305sbc

iTrader: (3)

If the oil still comes out the dipstick tube with the oil-filler cap removed, then you need another vent.

If you keep running without enough crankcase ventilation then you will start blowing oil out of most of your gaskets, and you will not be happy about that.

emeryz28

I'm not sure I understand the flow of pressurized air within the engine. The driver's side has a PCV valve but the passenger side has basically an elbow going to the intake. I just checked my old oil cap and there is no vent hole in it. I'm wondering if it's the new valve covers that are somehow not allowing it to vent.

305sbc

iTrader: (3)

That isn't relevant.

You need to test for excess crankcase pressure as I said, then go from there.
At this point, even putting your old valve-covers back on may not solve this problem.
It sound like you installed new valvecovers after getting your car back from the dealer.
You may have had a gasket leak before that the dealer repaired, thus not allowing the excess pressure to escape anymore.
But, guessing won't help, so do the test.

emeryz28

The new valve covers were installed when it went to the dealer to have them do the oil pump. It was running rough so they adjusted the valves and did a compression test, which checked okay.

You said, "If the oil still comes out the dipstick tube with the oil-filler cap removed, then you need another vent." Should I just take the cap off and drive it for a while to see? I could drill a small hole in the new cap since it wasn't very expensive. Or, would I need an additional vent on the passenger side?

The new valve covers came with tiny metal boxes that could be installed under the holes and I presumed that the tiny boxes should be installed for both the vent and PCV holes. Is this correct?

akanitro

iTrader: (2)

Do like Pound said and do a cylinder leak down test. A compression test isn't going to identify your problem.

emeryz28

Okay. I wasn't aware that a cylinder leak down test was different than a compression check. Also, Pound said I could do either to check it.

TreeFiddy

The compression check will show if you've got one cylinder with lower compression than the others, or if they are all generally low. What it won't tell you is why - could be rings, valves, head gasket, piston damage etc.

The leakdown test will tell you where the problem is, by listening for where the air escapes.

It's got to be blow-by either normal or excessive, like you suggested run it for a little bit with the cap loose (not off), and see if the dipstick leak ceases.

emeryz28

The cap is an unthreaded rubber stopper glued to a chromed cap, so it's either completely off or on tight. I will drill a hole in it and see how that works.

The dealer just did a compression check and, although the work sheet didn't state the specific numbers, it stated that compression was "good." I will contact the dealer and see if they have the actual numbers. The heads were just redone by a reputable machine shop and there was no oil on any of the old or new plugs.

I'm still wondering if the new valve covers are causing the problem but it is such a hassle to get the passenger side cover off that I will do some other checks first.

For my own information, if a perfectly good engine had a blocked PCV/vent system, could it cause the crank case to be pressurized and oil to come out the dipstick?

TreeFiddy

Definitely. Even a new engine will have some degree of blow-by, and if the pressure cant get out thru the pcv system, it will soon find its own way out.

emeryz28

Good. Can you explain how the flow of blowby is circulated through the PCV and vent system. For instance, why does only the driver's side have a PCV but the passenger side has a vent? Is it to vent the pressure regardless of the state of vacuum in the manifold, e.g., with vacuum in the manifold, the PCV valve opens and sucks the blowby into the intake plenum and with no vacuum the vent from the passenger side sends the blowby into the intake of the throttle body?

TreeFiddy

You have manifold vacuum, which acts on the pcv valve in one of the valve covers, which allows a regulated amount of crankcase gases to be sucked out.

The other valve cover should have the vent on it, to allow fresh air INTO the crankcase, replacing the air that the pcv valve sucks out. This vent should be a filtered air source, either integral with the vent, or via a hose that comes from the air cleaner.

emeryz28

Thanks. I think I understand it now. Hopefully it's just a vent issue.

305sbc

iTrader: (3)

Yes you can but you'll need to temporarily put something over the hole to keep debris out of the engine.
The boxes are baffles to keep excessive oil from escaping with the blowby.

I have seen the baffles & rubber stoppers that come with valve-covers come without any holes so that you can drill/place them how you like. Check that this isn't the case here, otherwise your flow would be stopped or severely limited.

I posted some info about dealing with blowby from high-mile engines here:
https://www.thirdgen.org/forums/tech...rator-pcv.html

You may need two vents, two PCV valves, or two of each to prevent problems from popping up.

emeryz28

Thanks. I pulled the chrome top off the oil filler cap, leaving a rubber stopper with a 1/2" hole in it, then wrapped a rag around it and drove it a while. There was no oil leaking from the dip stick in this configuration, however, when I put my hand over the oil filler cap hole with the engine running, I noticed some white smoke coming from the dip stick, which I had pulled out about 1/2" out of the tube.

I noticed that I have a 2088 PCV valve installed but Autozone's web site calls for a 1227DL. I don't know if the wrong PCV valve would make that much of a difference but I will definitely replace this later today.

If the new PCV valve doesn't do it, I suppose I will have to install more in the valve covers. Am I correct in assuming that the additional PCV valve would go on the driver's side where the existing PCV valve is located and the additional vent would go on the passenger side, or could I install two PCV valves on both sides?

305sbc

iTrader: (3)

That is progress!
A four cylinder and a V-8 both come from the factory with only one PCV valve installed, so it stands to reason that some PCV valves are larger or flow more internally than others. I don't have a good way to determine the flow of one and I normally just use generic valves from the wall-display .

It's your choice how to arrange your valves & vents, but your PCV will remove more contaminants from the engine if the valves & vents are separated. In your case that would be two valves on one valve-cover, and one or two vents on the other.
If you T-connect the two valves into a common line, then your PCV flow will not increase significantly. If you do increase the PCV flow significantly then you will probably have to adjust your idle ( min air-rate ) to compensate a bit.

I would keep a close eye on your blowby contents once you do this. If you start seeing greenish foam appear then you may be getting coolant into your oil or burning it in a chamber. Coolant creates a lot of steam and increases blowby dramatically. Your heads and intake were recently off for some reason, so this is a possibility to watch for.

emeryz28

I was planning to T into the existing PCV line with a second PCV right in the top of the oil filler cap. Would this be an exercise in futility or would it help to increase flow?

305sbc

iTrader: (3)

That would be fine. I was saying that it will probably not need an adjustment to the idle setting in that case.
You will probably want to run 2 vents on the other bank.

emeryz28

The driver's side was easy to install an extra PCV valve right in the rubber oil cap. The passenger side will be much harder to install an additional vent because I will have to remove the valve cover and drill a hole.

I'm hoping the additional PCV valve will fix the problem, but I haven't driven it yet.

sofakingdom

iTrader: (1)

There's youre clue, right there.

It's not the PCV valve; the car ran for however many miles with the one that was in it, and (I take it) was just fine.

If your new valve covers have a hole in the one side for the PCV valve and a hole in the other for the filtered make-up air that the system requires to replenish that drawn out by the PCV, then it's fine. Leave it alone.

The oil pump isn't causing this either. It sucks oil up out of the pan and pressurizes it into the tiny spaces between moving parts. All of its "output" is contained within the block casting. Since you didn't change the casting, none of that is any different either. Don't worry about it.

Your piston rings and all of that sort of thing didn't change by unbolting and re-bolting the heads. All of that is EXACTLY as it was before. Once again, let me remind you, if it was OK before, it's OK now. Leave it alone and don't waste time with "compression tests" because that's not the problem.

So, return to the "clue" up above.

When you put the heads back on, you probably noticed a port in the center of each, that has exhaust in it.

THINK about that concept for a minute. The guys that are talking about "blowby" are sort of close to the right track, although not quite. THINK about those exhaust ports in the heads, and what would happen if the intake gasket was bad right there.

OK, now that you've THOUGHT about it for a little bit, what would happen?

Exhaust gas would force itself into the crankcase and create pressure which would then blow oil out every possible hole, eh?

Pop your intake back off, and you'll find the gasket is damaged on at least one side, across the bottom, at the center.

Put all the "doom & gloom" scenarios of needing a new motor, "compression tests", messing with the PCV valve, and "maybe it's this maybe it's that" OUT OF YOUR MIND, and instead, THINK. It's absolutely amazing how powerful the human mind can be when allowed to do its job. Then proceed to THE ONLY logical explanation for the symptoms you are observing, and LEAVE ALL THE REST OF THAT STUFF ALONE.

See my signature for a helpful mental discipline when diagnosing.

305sbc

iTrader: (3)

I did mention that there could be a gasket sealing problem, though it is by no means certain at this point that there is one, or where.

As well as other types of gasket failures, I do see this on occasion:

http://i702.photobucket.com/albums/w...ng/EGRleak.jpg



In this case the user often complains of multiple oil leaks from the engine and overheating. Obviously there can be various levels of this kind of failure. Worn exhaust valve-guides have a similar but less severe effect on blowby.

edit: This engine had been taken out of service for the problem and left outside in the rain for a while. I got it after that to use as a core for an engine build.

usajay38

wow thats nasty

emeryz28

Thanks for the advice, sofakingdom. If I have to pull the intake manifold and heads off again I would just as soon drive it until it blows up. I have invested more than the car is worth in the last month and I think I am done dumping money into it. The only reason I did was because I've had the car since it was new and it has acquired a sentimental value over the past 20 years. Both head and intake gaskets are new Felpro and I was very careful to torque them to the prescribed specs. I can't imagine why the gaskets would fail already.

I drove the car today and I am still getting oil out the dipstick, but I also got a DTC 32 (EGR), so I need to look into this and see if an EGR issue could affect the PCV function. The car is a third vehicle and is just for running errands around town, so I may just live with it until it keels over and dies.

BTW, 305sbc, that is the nastiest looking engine I have ever seen.

305sbc

iTrader: (3)

Do you have a photo of your intake manifold gaskets?

It is likely you would have to only pull the intake manifold to address the problem mentioned above.

I assume you never got a code 32 before you pulled the intake and heads?

by the way, why did you replace head-gaskets in the first place?

emeryz28

I wish I had taken a picture of the intake manifold but got wrapped up and forgot. This is the first time I got a DTC 32. I replaced the head gaskets because the last time I did it back in 2002, I listened to the fool at Autozone who said that I should never put any sealant on the head bolts of a small block Chevy because it would adversely affect the torque setting (I guess I was just as stupid for listening to him). As a result, the heads started leaking coolant after a few years, probably through the bolts that went into the water jacket, but it was only towards the outside of the engine--at least primarily towards the outside--because I never smelled any antifreeze in my exhaust. I managed to keep it going for over 5 years by using the CRC head gasket sealer.

These are pictures of the old head gaskets that were on there from 2002 to 2011.

305sbc

iTrader: (3)

Holy Hell !!
I'm surprised it didn't leak from both sides immediately.

Did you use any sealant on your intake gaskets?

Did your gaskets look like this, with the center ports blocked off?

http://thumbs2.ebaystatic.com/m/m500...iYiuxg/140.jpg

emeryz28

No, it was from the Felpro head gasket set and it looks like the picture below.

The only sealant I used on the intake manifolds was on the edges that faced the China wall (valley) because the manual called for running sealant in the valley and up towards the intake manifold gaskets.

305sbc

iTrader: (3)

I always use high-temp RTV on the intake gaskets around the coolant and water ports at the very least, and often over the whole thing.
The gaskets shouldn't leak without sealant, but then again a lot of things "shouldn't" happen. I'm not much of a gambler.

I know that a lot of factory intake manifolds I work with have a pitiful amount of meat around the sealing surfaces, and I often end up using hardening epoxy to widen the sealing surfaces.

When factory intake manifolds see 200,000 miles or more, I often find that they have a lot of pitting and erosion around the gasket mating surfaces which makes it harder for the gaskets to seal. This is a time when building up and reforming the sealing surfaces with epoxy is a big help. If you have a TIG welder, then you can do it that way as well.
Using hardened flat washers under the bolt heads that hold down the intake manifold also help to distribute the clamping force more evenly and to get proper torque on the bolts.

Here's a pic of some of this sort of epoxy work. This was a case where I went a little over-kill on the sealing surfaces because the requirement with this job was absolutely NO leaks, using old parts on a 200,000+ mile engine. It was a work truck that gets parked inside on a shop floor, and was making a big mess daily. The intake was very pitted and eroded, especially around the coolant passages. This kind of stuff just happens with very high-mileage engines.

The screen is under an extra crankcase vent that I added to the front of the manifold to vent the lifter-valley.
I know the RTV looks pretty sloppy on the outside, but it was intentional and this pic is while it was still setting up. It can be trimmed and cleaned away after setting up. Looks weren't a priority on this work-truck.

http://i702.photobucket.com/albums/w.../DSCF5800b.jpg


I believe you can see the hardened washers under the bolt-heads in this pic below. You can also see that I used the high-temp RTV all the way around the thing just to ensure there were NO leaks and the truck could go back into service without more interruption. It had a good bit of blowby (no engine damage though) and weak gaskets that were puking oil out from multiple places on the intake and the oil pan. In the end the leaks were all stopped and it has been running happily for over a year like that.

http://i702.photobucket.com/albums/w.../DSCF5812b.jpg

305sbc

iTrader: (3)

By the way, just how much blowby do you see coming out at idle if you remove the oil-fill cap?
Is it a pretty crazy amount or just typical for a high-mile engine?
Does it increase a lot if you rev the engine a little?

emeryz28

It's hard for me to tell because I've never seen how much blowby comes out of a high mileage engine. I have two PCV valves installed on the driver's side. When I open the oil filler where one of the PCV valves is installed, there isn't a lot of blowby coming out even when I rev the engine.

Also, I test drove it today and the oil is not leaking out the dipstick. I'm not sure if this was due to the fact that I pushed the dip stick all the way down as it should be or whether it was my fixing the EGR Code 32 last night. There was a solenoid valve with a coil on it that accepts two vacuum lines--one comes from the EGR valve the other from the throttle body. The plastic fitting was broken where the EGR line went into the solenoid valve. I was able to repair it with some superglue. Could the EGR valve problem have anything to do with the blowby?

I don't want to speak too soon, but I think the blowby problem has disappeared.

Next time I am at Autozone, I'm going to pick up some starting fluid and check to see if the intake manifold is leaking.

305sbc

iTrader: (3)

If your exhaust was leaking out into the crankcase (as in my nasty pic above) I would expect it to put on a pretty good show if you remove the oil fill cap and rev the engine up.

The EGR? logically, no it should not have anything to do with the blowby.
I'm confused on the dipstick issue. I was assuming you had oil coming out the top of your dipstick tube, not the bottom. I thought this because heavy blowby will pop the dipstick up out of the tube and sometimes cause oil to leak from there. In fact, the dipstick popping up is a sure indicator of either excessive blowby or a malfunctioning PCV/vent system.
I would think that the dealership that serviced your car would have reinstalled and sealed your dipstick tube correctly.
So, please clarify if the oil was coming out the top or the bottom of the tube?

An intake gasket can leak on the inside of the engine where you probably would be able to detect by normal testing.
I hope your problem is solved, - whatever may have done it.

emeryz28

I sealed the bottom of the tube myself with Permatex as per the manual. The oil was leaking out the top. You are correct--it never leaked out the bottom. I guess if the dealer replaced the pan, then they would necessarily have to reseal it anyway.

In the process of troubleshooting the problem, I discovered that I had the wrong PCV valve installed. In addition, I decide to add a second PCV valve where the oil cap screws in because the PCV valve fit so perfectly into the rubber plug there and I never have to add oil after an oil change anyway.

While all this was going on, I had read here that the excess pressure could cause the seals in the rest of my engine to blow out, like the oil pan gasket, etc., so as a precaution, I never actually pushed the dipstick all the way back in because I was concerned about the pressure and wanted to leave an escape route.

Today, I decided to push it all the way in and drive it. I noticed that no oil came out. So, to make a long story even longer, I'm not sure what happened to fix the problem, or whether it is even permanently fixed. I'd hate to speak too soon. When I drove it today, I didn't take it above 3,000 RPM. I guess the test will be to see if it comes out at higher RPMs. Although, I have found that the older I get, the less need I feel to operate in the upper envelope. Thanks so much for all your help on his. I'll let you know if it recurs. I sure hope not.

emeryz28

I found this test for the PCV system in the shop manual. I am going to try it tomorrow.

sofakingdom

iTrader: (1)

That test will not be effective if the intake gasket has the leak described above... because, if there's exhaust gas pressurizing itself into the crankcase, you could have 10 perfectly working PCV systems on there, and there STILL won't be any vacuum. IOW, the "test" will "fail" the PCV system, but the PROBLEM won't BE the PCV system, the PCV system is merely the SYMPTOM. You can replace every single piece of the PCV system every day for the rest of your life, and twice on Sundays just for good measure, and NEVER make the slightest dent in the REAL problem.

Also note that if the car is idling, there is MUCH less pressure in the exh system generally, than when it's under load; just checking it sitting idling in the driveway may not be a very good test to begin with.

And also, a stopped-up exhaust (which would usually be a catalytic converter with busted-up guts) will cause HUGE pressure in the exhaust, which in turn will cause all sorts of weird things to happen. And this, unlike most of the other potential REAL causes of your symptom, can possibly come and go, as the broken-up chunks of honeycomb material in there wander around and rearrange themselves. And if that's really the situation, it'll be back.

All in all, I doubt you'll find that the "test" is anything remotely near "conclusive". Factory service manual procedures are designed for NEW CARS, where certain assumptions can be made about the overall mechanical condition of the engine; they often don't translate very well to cars with lots of miles, or modifications of any kind. You're going to have to be a little more open-minded.

emeryz28

The symptoms have disappeared for now, but you make a good point about a clogged exhaust--especially on a 20-year-old car. I imagine there's a lifespan to the catalytic converters. I will keep an open mind about that. Thanks again.

brandon lee

ok i have a l98 and i just replaced my intake gasket and stop leaking for a while then started again but the motor had been rebuilt before i bought it the car only has 75000 miles on it i was thinking that there might be building up to much presser and making that china wall leak any ideals