Hi Guys,

I recently emptied out my oil catch can and to my surprise it had been collecting water. It would have easily been 2L of water.

I also took the block breather hose out to have a look to see if the water was going back into the block and saw a large build up for white greasy froth build up. On touch it it's like greasy blubber fat looking and has a strong fuel smell. I assume the fuel smell is because my car is running rich and it maybe just the excess fuel running down the cylinder walls.

As for the water I take it to be a collection of condensation as my car runs a large oil cooler without a thermostat sandwich plate.

Anyhow my question is if anyone knows what the greasy froth build up is? or if it's damaging to oil supply to the motor.

BTW pics where taken after a drive and motor had cooled down but still a little warm so it doesn't look like the substance melts away on heat.

Edited August 7, 201212 yr by MKI4EVA

There is water getting into the oil somewhere. Have you changed the oil recently. Is there oily film in the radiator. Are there air bubbles in the radiator with the engine running.

Yeah, by that description it sounds like a head gasket or block issue.

Just curious, but what year Z has a 2 liter oil catch can?

How often do you drive the car, and how far each time? Maybe you just need to drive it farther on each trip.

Just curious, but what year Z has a 2 liter oil catch can?

How often do you drive the car, and how far each time? Maybe you just need to drive it farther on each trip.

I'm with Zed. Looks like excessive condensation in the crankcase from not running the car to full temp many times over (lots of short trips).

Pull the valve cover and see what's inside. Whatever it is, it's not good.

When you pull the dip stick, what does it look like?

Edit: Is this the hose from the valvecover or the hose to the PCV vavle from the crankcase. If it's to the PCV valve, safe top say the PCV valve hasn't worked for some time.

A picture of this catch can and it's plumbing would be helpful.

If you see dropplets of water are they clear or green like anti freeze

Edited August 8, 201212 yr by Bruce Palmer

There is water getting into the oil somewhere. Have you changed the oil recently. Is there oily film in the radiator. Are there air bubbles in the radiator with the engine running.

Yeh I noticed this was happening some months ago after I first purchased the car. So the first thing I did was to change the oil. Oil colour looked fine and wasn't browny and there was no coolant in the oil as far as I can tell.

I have not tried to see if there are bubbles in the rad as the car is warming up. I'll try that and get back to you.

Just curious, but what year Z has a 2 liter oil catch can?

How often do you drive the car, and how far each time? Maybe you just need to drive it farther on each trip.

It's a 1971 and I may have exaggerated the oil catch can size - it's a big unit and i'll put up a pic shortly. I drive the car say 3-4 times a week and it would just be getting around town. They are quite short drives. The car was set up for track so it maybe just a case of being too cool for punting around town.

Pull the valve cover and see what's inside. Whatever it is, it's not good.

When you pull the dip stick, what does it look like?

Edit: Is this the hose from the valvecover or the hose to the PCV vavle from the crankcase. If it's to the PCV valve, safe top say the PCV valve hasn't worked for some time.

A picture of this catch can and it's plumbing would be helpful.

If you see dropplets of water are they clear or green like anti freeze

I haven't pulled off the valve cover as yet. Dip stick seems fine in terms of the colour of oil coming out. Nice a black oil not a brown of any sorts.

That pic is of the crank case and the hose is off the crank case. I run a pipe from the valve cover to the oil catch can and a exit hose from the oil catch can back into the crank case. I assume this is normal. Obviously there is a vent filter on the oil catch can itself.

I'm going to run a radiator fluid chemical test this week and that should settle things.

I have done a cylinder compression check on all 6 chambers and they all read consistent 170'ish PSI. It's a low comp motor with a mild cam so nothing special and is pulling roughly 150PS at the wheels (L26)

It sounds like there is not enough air flow thorugh the crankcase due to the PCV valve having been removed. Consider putting a PCV valve back on.

The PCV valve was on, I just took it off to show the goo that was in there.

Hmm maybe the oil catch can breather needs to be cleared out as that's the only part I haven't cleaned. It's just a cylindrical air filter.

Edited August 8, 201212 yr by MKI4EVA

The PCV valve was on, I just took it off to show the goo that was in there.

Hmm maybe the oil catch can breather needs to be cleared out as that's the only part I haven't cleaned. It's just a cylindrical air filter.

Ok. Where does the PCV valve pull the air from? Maybe it is getting air from the filter rather than from the crankcase. If the air does not circulate through the engine it will not remove the moisture and you get the goo build up. Try taking the hose off the valve cover and place the filter there. Route the PCV to the side of the block.

The PCV valve was on, I just took it off to show the goo that was in there.

Hmm maybe the oil catch can breather needs to be cleared out as that's the only part I haven't cleaned. It's just a cylindrical air filter.

A-ha! You have a PCV valve but no connection to the intake!

This means that the PCV valve never sees vacuum and thus never opens. Therefore. your crankcase is not adequately vented. The PCV valve is designed to open with vacuum pulling on it (light-throttle conditions) and close at atmospheric (WOT conditions). Without a connection to the intake, all the valve sees is atmospheric pressure.

I suggest ditching the PCV valve altogether and simply venting the crankcase through that catch can. This is the typical (but not optimal) setup for anyone running triple carbs.

The valve cover pipe goes into the catch can, then theres the PCV hose that goes into the catch can as well. The catch can itself has a vented filter and a drain plug. But since the catch can isn't catching any oil I might vent the PCV to atmosphere.