[Von]

I dont't have any idea why but I think the harder I drive my car the more oil that sprays up on to the underside of my hood. Last night it was so bad that it got on the fire wall, the passenger fender well and all over the passenger side of the engine. It has done this multiple times and I am getting VERY agrivated. PLEASE HELP ME!!!!

[pete]

Is it definately Engine Oil & not Power Steering pump oil ??

If it is engine oil, likely chance is a Blocked Breather. If you take the Rocker Box filler cap off with the engine running is there a lot of pressure there ?

[dave-r]

There are so many places the oil could be coming from it is impossible to help you very much. When it gets everywhere it is often very hard to tell exactly where the source is. But you need to locate the source of the leak.

If it is not obvious where it is coming from you will need to CLEAN the whole engine first. Then start the engine and have good look. If it does not seem to be leaking at idle try hitting the throttle a couple of times. If still not evident take it for a SHORT drive and then pop the hood for another look. Hopefully you will be able to see where the oil is coming from before it soaks everything.

[Von]

could my engine be pressuring up and oil comming out of the dip stick tube?

[dave-r]

If the crankcase ventilation system is not working - yes.

[VON]

on my valve covers I have a fill cap on each side and a pcv valve on ONE. If I dont have a breather on the opposite side of my pcv valve could it cause this?

[dave-r]

Without a crankcase ventalation system the gasses that escape past the piston rings build up in the sump and can make the engine run rough or even force oil out of the engine.

A 'breather' on each valve cover will alow these fumes to escape into the atmosphere.

However this makes the car interior smell and the Green Party play hell about it. So we have Positive Crankcase Ventilation (PCV) instead.

The system works like this.

The pcv valve sits on the end of a rubber hose which is connected at the other end to a manifold vacuum port on the base of the carb.

The valve itself sits in a rubber gromet in the top of one valve cover (doesn't matter which one).

The suction from the manifold draws air and fumes out of the engine crankcase (below the pistions) and back into the combustion chambers where it is burnt with the air/fuel mixture. The valve is there to regulate the flow of air at different throttle positions.

To draw air out of the engine you also need an inlet for air. On the valve cover opposite the one with the pcv valve there has to be an air inlet. This is normaly a 'breather' or a filter that is connected to the air filter case with another rubber hose.

If the air inlet was blocked (or not there at all) it would not cause pressure to build in the system as it is being drawn by the carb. Rather there will be low pressure in the sump and there would be poor air circulation and sludge building up.

However if the pcv valve is clogged or stuck closed the pressure cannot get out except via the air inlet. And if that gets blocked as well it cannot get out at all causing the problem you may have.

The valve should rattle when you shake it. If it does not soak it in thinners/fuel or solvent and try again. If it remains blocked you can buy a new one.

You can test the system is working by removing the air inlet and placing a scrap of paper over the hole in the valve cover. The suction into the hole should be enough to hold the paper against it.

Make sure the air inlet is not clogged either so that plenty of air can circulate.

I hope this is the problem because it is easy to fix.

[john]

check the oil pressure switch- I've seen them pass oil if they break or leak at the seam.

john

[frank]

what about the rear main seal? the flywhl will sling the oil everywhere .....

[LITEMUP (Von)]

another problem associated with that: you will see a picture of the passenger side of my engine bay in the thread titled a/c hoses. I have two K&N breathers in that side of my valve cover. I ahve a pcv valve going into my carb on the driver side valve cover. First, i do have baffles on the inside of my valve covers and oil still leakes out of both breathers. my pcv valve is not plugged. it is not as bad as mentioned above earlier but I am still having problems. Second, why do i have to have a pcv valve? I have a friend with a C**vy and he doesn't have one and he has no problems. why cant I just have a breather and a cap on each side? If a concern it's a modified 360

[Dave-R (Roppa440)]

Just to remind people why you need breathers or a crankcase ventalation system....

Some of the combustion gasses in the chambers get past the piston rings causing the engine block to become pressurised. The more worn the rings the worse this is.

So to prevent this pressure from blowing your valve covers off, the covers need to be vented to the outside. This is what these 'breathers' are for. Pressure from the sump then finds its way up past the cam, into the valley, and out the valve cover breathers. Fumes from the hot sump oil get mixed in with this also so the hydrocarbon levels of these fumes is high.

Now you could just stick one breather on each vave cover and leave it at that. But these fumes stink and they will find there way into the air vents and into your clothes making you stink too!
Again, the older or 'looser' the engine, the worse the problem.

Now for emmisions reasons the factory prefers these fumes to be collected and mixed with the intake mixture so it can be burnt in the cylinders. So breathers that vent to the outside air are out of the question.

So the factory fits a pipe from the carb base (manifold vacuum) that runs to one valve cover. This sucks the fumes out of the crankcase and into the intake manifold. For this to work you also need an air intake. So a breather is placed on the opposite valve cover to allow air in. This breather usually has a pipe going to the air cleaner base so that only filtered air is sucked into the engine.

So in this system air is sucked in one side (passenger) and is drawn through the crankcase, out through a PCV valve in the drivers side valve cover, and into the intake manifold.

Notice I said the vacuum was applied to the drivers side valve cover. This is because oil from the spinning crank is thrown from the crank up into the passenger side valve cover. Any suction here would draw out a lot of liquid oil at high rpm or hard cornering. So the suction is applied to the drivers side.

Air is being sucked into the valve cover on the passenger side so this tends to stop any oil thrown up by the crank from exiting the breather.

To test the system is working right remove the breather from the passenger valve cover and hold a piece of paper to the hole in the valve cover. Suction into the engine should grab the paper and make it stick to the opening.

I think your problem Von is that with two breathers on that side the air speed being drawn into the engine is halved. So there is nothing to help stop the oil splashing up and out of the breathers. I bet if you tried that test you will find there is little or no suction through your breathers. Try the test after blanking one off.

Also if you do not have a crank windage tray (oil scraper), or have one that does not work very well, then the amount of oil being thrown up by the crank could be excessive. then no amount of baffling or suction will be able to stop oil from being thrown out the breather.

[Jeff Maxwell (Redchalleng]

Dave, again I tip my hat to you. I used the search function to figure out more about my valve covers and what goes into and out of the covers. When the engine was upgraded to a 340, they put this silver thing at one end of the valve cover, and that sucker leaks oil. In fact, when I drove it Friday to show off to a C**** fan who has his own 69, he saw a puff come out when I stopped the car. Oil comes out of this, and now I know why. I'll check the other side, but I'm sure it doesn't have a breather. I think neither side has a hose back up under the Shaker, but I found a picture on your site of some engine ready to drop in with a Shaker that had a hose going back under. Now I need to know what kind of hoses and PCV valve that should be on it. It has the MP covers, and I was thinking I should replace them with the standard painted ones. Mine are orange, is that standard MP option or did prior owner doctor them up?

[Dave_R (Roppa440)]

The MP cast ally covers come painted wrinkle black. Do you want me to find and scan some images of the stock system or do you have that covered?

[Jeff Maxwell (Redchalleng]

Thanks, Dave. I've seen enough stock. I just didn't know how my MP got orange. Somebody doctored them up, huh? I have another picture of them black, so I'll bet I know how they got orange.

[Caparco]

Just to remind people why you need breathers or a crankcase ventalation system....

Some of the combustion gasses in the chambers get past the piston rings causing the engine block to become pressurised. The more worn the rings the worse this is.

Dave I have lots of fumes in my car as well, and smoke comming from both my valve covers "blow by" they say. (valves have no sludge,that can be seen-just worn oil -needs change)could this be my problem all along as this goes right back in my engine through the PCV?

I'm reseting timing (again) tomorrow...thanks for all the help!

[insuranceguy]

Von,


I just had the same problem 2 weeks ago. When I nailed it, the engine smoked as much as the tires

When I cleaned it up again, I noticed that the grommet that holds the breather cap on the left side facing the motor did not have a hole cut in the bottom of it. I could not tell until I stuck my finger in and found the obstruction. Here is a photo that I took during installation, and you can see what the problem is.

(If I had paid better attention, it would have saved me a hell of a mess)

Hope your fix is as easy.

Todd