losing oil

[KreagerM]

I'm in need of your guys opinions on this one. I have a 65 with a fresh (5,000 miles) 289 bored .30 over (compression around 9.5:1), with an air gap intake, gt-40 aluminium heads, edelbrock performer carb, 1.7 rockers, tall valve covers and a mild cam. The problem I'm having is that I'm losing oil. From where I don't know, so I want to see what you all think.

After changing the oil (10w30) I started hearing a slight tick (days later) so I checked my oil level. It was at the add line. Thought this was strange because I just put in 5Q of oil when I changed it and the levels were perfect. And this was just after a few days of driving. So I watched it closer and I found that after hard driving (above 4K) I lose about 1/4-1/5th of a quart and this could be after an hours drive.

So I checked all my gaskets and they are perfect (just rebuilt). pulled my plugs, they look normal. Had a buddy watch me excellerate and no smoke is coming out the tailpipes. No smoke during start ups after sitting all night. I do notice that there is oil in my filler cap and it looks like it's misting on to the valve cover (concerned about this). The pcv valve is hooked up to the carb and this looks normal. The valve covers do have the baffels under the pvc and filler ports.

At this point I'm stumped. I'm thinking is the oil steaming away? The engine runs at normal temp (180 therm) though. Should I try a thicker weight oil, it is summer time and I didn't notice this issue until the weather got warm. I really don't know what to do. I'm open for all suggestions, any help would be greatly appreciated.

 

[ForceFed70]

There's only 3 places the oil can go...

- Into the combustion chamber where it's burnt. (rings, valve seals, PCV)

- Onto the ground.

- Into the cooling system.

It's got to be 1 of those 3 scenarios. You'll have to investigate each.

 

[dennis112]

To solve a major consumption problem on a new engine I moved the PCV valve from the rear passenger side valve cover to the front of the driver's side. Not as pretty but it certainly works. I also found that the intake gasket (underside) was saturated with oil.

Do you have the restrictor in the valve cover under the PCV valve? If not, rubber ones are available in the aftermarket. I found some made by Moroso that fit my 1 1/4 " hole perfectly.

 

[KreagerM]

Good advice but the valve covers I have, have the long neck for the filler cap. I do have the restricter plates under both the pcv and the filler neck though. I just put in a new pcv valve so hopefully that helps out, should know soon.

 

[fvike]

There's only 3 places the oil can go...

- Into the combustion chamber where it's burnt. (rings, valve seals, PCV)

- Onto the ground.

- Into the cooling system.

It's got to be 1 of those 3 scenarios. You'll have to investigate each.

Umm, 4 places. I have a console mounted mechanical oil press gauge... and when that sucker started to leak, I didn't notice until I had oily footprints one day!
Oh well, at least my passenger side floorboards won't rust!

 

[pabear89]

I'm in need of your guys opinions on this one. I have a 65 with a fresh (5,000 miles) 289 bored .30 over (compression around 9.5:1), with an air gap intake, gt-40 aluminium heads, edelbrock performer carb, 1.7 rockers, tall valve covers and a mild cam. The problem I'm having is that I'm losing oil. From where I don't know, so I want to see what you all think.

After changing the oil (10w30) I started hearing a slight tick (days later) so I checked my oil level. It was at the add line. Thought this was strange because I just put in 5Q of oil when I changed it and the levels were perfect. And this was just after a few days of driving. So I watched it closer and I found that after hard driving (above 4K) I lose about 1/4-1/5th of a quart and this could be after an hours drive.

So I checked all my gaskets and they are perfect (just rebuilt). pulled my plugs, they look normal. Had a buddy watch me excellerate and no smoke is coming out the tailpipes. No smoke during start ups after sitting all night. I do notice that there is oil in my filler cap and it looks like it's misting on to the valve cover (concerned about this). The pcv valve is hooked up to the carb and this looks normal. The valve covers do have the baffels under the pvc and filler ports.

At this point I'm stumped. I'm thinking is the oil steaming away? The engine runs at normal temp (180 therm) though. Should I try a thicker weight oil, it is summer time and I didn't notice this issue until the weather got warm. I really don't know what to do. I'm open for all suggestions, any help would be greatly appreciated.

If your sure there is no leaks anywhere, then Windage from the crankcase could be blowing it out your cap.
you did say after an hour of running 4k.

PB

 

[ForceFed70]

Umm, 4 places. I have a console mounted mechanical oil press gauge... and when that sucker started to leak, I didn't notice until I had oily footprints one day!
Oh well, at least my passenger side floorboards won't rust!

I'd sorta lump that one into "onto the ground" catagory.

I had the same thing happen to me. Which is why I'll never use one of those types of oil pressure guage again. The hose they use with the guage is way too fragile and can easily break or melt. Electrical senders for me from now on.