High oil consumption

[Torqued]

I've had a 1990 Escort for a couple of years and oil started appearing in the air cleaner. I checked for a PCV valve and this model doesn't have one. (According to Ford) The crankcase gas goes through a 2 stage orifice directly into the intake and any excess goes to the air cleaner. Compression is 130 on all 4 cylinders. If I remove the hose from the top of the valve cover the blowby seems excessive to me and contains lots of oil drops. Could a valve problem cause this? Any other ideas? The engine is a 1.9 CFI with 190,000 mi.

[chevyn0va1]

Originally Posted by Torqued

I've had a 1990 Escort for a couple of years and oil started appearing in the air cleaner. I checked for a PCV valve and this model doesn't have one. (According to Ford) The crankcase gas goes through a 2 stage orifice directly into the intake and any excess goes to the air cleaner. Compression is 130 on all 4 cylinders. If I remove the hose from the top of the valve cover the blowby seems excessive to me and contains lots of oil drops. Could a valve problem cause this? Any other ideas? The engine is a 1.9 CFI with 190,000 mi.

I always thought blowby was a sign of bad valve seals.

[A. Souphound]

Originally Posted by Torqued

I've had a 1990 Escort for a couple of years and oil started appearing in the air cleaner. I checked for a PCV valve and this model doesn't have one. (According to Ford) The crankcase gas goes through a 2 stage orifice directly into the intake and any excess goes to the air cleaner. Compression is 130 on all 4 cylinders. If I remove the hose from the top of the valve cover the blowby seems excessive to me and contains lots of oil drops. Could a valve problem cause this? Any other ideas? The engine is a 1.9 CFI with 190,000 mi.

Torqued,
From your description, it sounds like you believe it is a crankcase ventilation problem.....I agree that it's a possibility, although it is a high mileage engine.
On some of the CFI engines the crankcase ventilation filter is part of the filler cap. If the filter is clogged crankcase pressure can build up. I would change the oil filler cap.
With that much oil being returned to the intake manifold, I would expect an engine to smoke ....does it?

Alvin

[Torqued]

It smokes like a forest fire. The cap doesn't have any filter, It's sealed. No fresh air is brought into the crankcase with this system. There's only one hose from the end of the valve cover to a tee on the side of the air filter. Another hose from the tee goes to the intake manifold through an orifice. The excess that can't be taken up through the intake manifold goes into the air filter. I expect that on a new engine there would be little blowby and air would flow from the air filter through the tee into the intake manifold. On this older one, the blowby is excessive and over producing what can be accepted through the manifold, dumping the excess into the air filter, along with lots of oil.
I was considering replacing the entire engine but since I'm now suspecting it may be only a valve guide or seal problem, I'm tossing that out for discussion to see if it's worth pursuing.

[chevyn0va1]

Originally Posted by Torqued

It smokes like a forest fire. The cap doesn't have any filter, It's sealed. No fresh air is brought into the crankcase with this system. There's only one hose from the end of the valve cover to a tee on the side of the air filter. Another hose from the tee goes to the intake manifold through an orifice. The excess that can't be taken up through the intake manifold goes into the air filter. I expect that on a new engine there would be little blowby and air would flow from the air filter through the tee into the intake manifold. On this older one, the blowby is excessive and over producing what can be accepted through the manifold, dumping the excess into the air filter, along with lots of oil.
I was considering replacing the entire engine but since I'm now suspecting it may be only a valve guide or seal problem, I'm tossing that out for discussion to see if it's worth pursuing.

you know in my escort the pcv valve is in line in a hose and unless you know its there its hard to see. just a thought.
I have seen like alvin said about a vented oil cap. you sure it dont have (or supposed to have) one? I have bought cars where people adding things that didnt belong to that car like one time a wrong radiator cap

[Torqued]

When this first started to happen I went to a local Ford dealer and they let me look through their shop manuals. That's where I found out it doesn't have a PCV valve as most cars do and it uses a 2 step orifice that allows a limited amount of crankcase gas into the intake manifold depending on engine load. There is no fresh air vented into the crankcase. Crankcase gas is sucked into the intake manifold through the orifice and to keep the crankcase from being drawn down by vacuum, fresh air is vented into the hose from the valve cover and then goes to the orifice assy. If the blowby gets excessive (my car) then there's too much crankcase gas and the excess goes the other way into the air cleaner. In my case it carries a lot of oil and makes a mess. If I take the oil filler cap off when the engine is idling, I get oil and blowby out of the valve cover. This is with the hose to the intake manifold still hooked up. If I disconnect the hose from the tee to the orifice, I have strong vacuum from the hose.
I have a factory service manual that I bought used and it doesn't even mention a PCV valve. It doesn't go into detail about the emissions systems (a different book) but the regular servicing schedule doesn't mention a PCV valve either. The emissions book I read at the dealership is where I found out there isn't a PCV valve.
I've been picking at this problem for over a year, but the smoke and oil consumption have finally made me park the car until I can fix it.
The spark plugs are all clean, no trace of oil. That kept bugging me and that's why I started to wonder if I have a valve seal/guide problem.
I can afford to take my time and check things out if anyone has any ideas, but I'm not inclined to spend huge amounts of money. It's a commuter car and has otherwise been very reliable and if the repair is economical enough, I'll fix it. Otherwise it's off to the big garage in the sky.

[A. Souphound]

Originally Posted by Torqued

It smokes like a forest fire. The cap doesn't have any filter, It's sealed. No fresh air is brought into the crankcase with this system. There's only one hose from the end of the valve cover to a tee on the side of the air filter. Another hose from the tee goes to the intake manifold through an orifice. The excess that can't be taken up through the intake manifold goes into the air filter. I expect that on a new engine there would be little blowby and air would flow from the air filter through the tee into the intake manifold. On this older one, the blowby is excessive and over producing what can be accepted through the manifold, dumping the excess into the air filter, along with lots of oil.
I was considering replacing the entire engine but since I'm now suspecting it may be only a valve guide or seal problem, I'm tossing that out for discussion to see if it's worth pursuing.

You probably know there are several schemes used by Ford for crankcase ventilation, and yours is the calibrated orfice type. Fresh air is brought into the engine from the air filter housing, and there is a coarse air filter in the housing which the hose is attached to.
You are probably right about the excessive blowby being due to wear. If the engine smokes more when you accelerate....it's worn rings. If you decelerate and then punch it, and there is more smoke then....it's valve guides/seals.
There may be one other thing to check. Remove the valve cover and see if the oil return drains in the head are open. I have seen these drains sludged preventing oil from returning freely to the crankcase and pools around the valves. With pooling and worn valve seals, oil is sucked into the cylinder on the intake stroke, and blows oil on the compression stroke.

Alvin

[chevyn0va1]

If the engine smokes more when you accelerate....it's worn rings. If you decelerate and then punch it, and there is more smoke then....it's valve guides/seals.

I never knew that

[Torqued]

It definitely smokes more on acceleration. But the compression is good at 130 on all 4 cylinders. It's was burning a quart every 75 miles when I parked it. It would burn worse if I got on the throttle or drove at more than 55 mph. I will check out the oil return drains like you mentioned. Thanks for the info.

[delta148]

Originally Posted by Torqued

I've had a 1990 Escort for a couple of years and oil started appearing in the air cleaner. I checked for a PCV valve and this model doesn't have one. (According to Ford) The crankcase gas goes through a 2 stage orifice directly into the intake and any excess goes to the air cleaner. Compression is 130 on all 4 cylinders. If I remove the hose from the top of the valve cover the blowby seems excessive to me and contains lots of oil drops. Could a valve problem cause this? Any other ideas? The engine is a 1.9 CFI with 190,000 mi.

TORQUED the problem with the excessive oil in the air cleaner & blue smoke is; the 2 piece orifice system consist of a baffle & the valve, the baffle is the rectangle box that connects to the crankcase breather filter & the valve is connected to main vacuum, the valve operates the same as a conventional pcv valve and will stop up as a pcv valve wood, when the valve stops up the valve is left open. the excessive pressure you stated when the hose is disconnected from the valve cover is normal at idle speed if you notice once the engine is revved up the pressure lesions; now at idle the orifice valve is about 90% closed letting about 10% pressure pass from the crankcase doing so limiting oil from passing into the breather filter & to the intake manifold at the main vacuum, when the valve stops up it is left wide open at idle and pulling oil through the system from the main vacuum. Ford designs of this system works exactly like the conventional pcv system except when the orifice valve stops up, raising the compsumion of oil the valve must be replaced, but the catch is, you can only buy this valve from Ford and it cost around $50.00 -to- $60.00, compared to the conventional pcv valve which is about $3.00. REPLACE THE ORIFICE VALVE, the one closes to the intake, that will solve the problem, but these engines that have high mileage & have not been maintained regularly have sludge build up in the valve cover baffle and in the main valve in the intake manifold; so if that takes care of the problem but it starts the oil consumion again eventually the baffle inside the valve cover needs to be cleansed & the intake manifold where the main vacuum enters should be checked for sludge/build up and cleaned. You can also have someone redesign the Orifice/baffle system to use the conventional pcv valve, jest make sure they reconnect the hoses to the TBI housing and to the EGR system, which is very important. Good Luck, delta148