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Smokescreen?

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I've seen the same thing (though not all THAT blue) from a burst of oil sucked through a PCV unit (from the oil separater into the carbs)... and took a fair length of time to clear out.
 
The Lucas additive didn't really seem to make a difference. Raising the idle to about 850 - 900 rpm helped a little bit. Also after about 20 miles of driving the smoke was not nearly as pronounced. What I did notice was a significant increase in my oil pressure (gauge reading 80 psi cold), which appears to have been enough to blow oil past the dipstick, which doesn't have the greatest seal in the world. I first noticed it driving home this afternoon when I saw a few droplets on the extreme right side of the windshield...even though it wasn't raining. I traced them to coming up from the hood. When I popped the hood, Oil spewed EVERYWHERE, but it was far worse from the dipstick back. It also left a really nice puddle of gooey oil on the ground.

The other thought might be that it spewed from the filter. Baby Blue's motor is fitted with a screw-on type adapter, but when I checked, the oil filter was completely devoid of any oil on the outside. I thought I might have blown the pan gasket, too, but it appears intact, although with the quantity of oil, I'm going to have to clean things up a lot to see what happened.
 
Oil pushing out the dipstick tube would not be caused by oil pressure. It would be caused by pressure in the crankcase caused by combustion gasses and pumping from the pistons. I think you have blown the oil filter seal or oil filter adapter seal or gasket due to the greater oil pressure caused by the Lucas stuff. Did you check your oil level?
 
Oil level at cold is midway between the "max" and the "add" marks on the dipstick. This morning it was a 1/4" under "Max" when the engine was warm.

I think you're right and it may be the filter seal. When I reached under the filter, I felt oil. There was also a fresh drop of oil directly under the filter. Oddly, though, when I wiggle the dipstick there is oil around the tube as well. How would the oil get work it's way up, out the hood and onto my windshield?
 
Make sure your crankcase ventilation system is working. Remember that yellow plug on the intake manifold did not look right. How is the front cover vent connected to vacuum? It should go through a PCV. It's not all your problem, but it needs to be right to prevent oil from blowing past the rear crank scroll.
 
Here's the problem with my crankcase ventilation -- In '69, they used an air pump and a canister. The air pump...well, it's gone. Somewhere in this car's 45 year history, one of the P.O.'s decided to remove at least part of the emissions gear. The air pump was what hooked up to the yellow plug. I still have the tubes coming off the carbs and going into a canister attached to the front of the engine. Curiously, the vacuum line from the distributor to the carbs was disconnected when I first got the car. I'm wondering if that was by design and maybe by hooking up the vacuum without the "other half" of the air pump, I'm sucking things into my carbs that shouldn't be going into it.
 
You can plug the vacuum ports on the carbs and instead run the hose from the timing cover to a "flying saucer" PCV connected at the intake manifold. I've got a PDF on 1275 ventilation, can't figure out how to post it, so I'll email it to you. (I think I still have your email)
 
All the air pump did was to pump air into the exhaust manifold to burn up any fumes that EPA didn't want getting into the atmosphere. Shouldn't really affect crankcase ventilation. If you are blowing oil out of places it shouldn't blow out of crankcase venting is something you need to look into.

Kurt.
 
I decided the best course of action was to go back to square one. I drained out the oil with the Lucas treatment and changed the filter. While waiting for the oil to drip out, I went back to re-check some of my work on the cylinder head. A couple of bolts needed to be torqued down again. I also found that the bolts attaching the carbs to the head all needed to be tightened up, too. I decided I'd wait until I put the oil back in to pull the valve cover gasket.

As I'm refilling the engine with oil, I start to hear fluid hitting the ground. I look and see HUGE quantities of fresh oil dumping on the ground. My heart begins to sink...I thought I had blown up the engine at worst, or blown out the pan gasket, at best. As I start looking for the leak, I see that oil is coming out from under the valve cover. Even though it made a huge mess, it was probably a blessing in disguise. I'm thinking that oil leaking from the valve cover was seeping into the intake.

I ended up dumping about a quart on the ground. I pulled the valve cover, rechecked the valve adjustments, checked to torque on the head bolts (one needed to be torqued down) and spent a bit more time sealing the valve cover back up again. I'll put the missing quart in tomorrow morning, fire the car up and see where we stand. I still think I may have crankcase ventilation issues, but they were probably being compounded by the oil leakage issues, too.
 
Does the oil separator ever need to be emptied or cleaned out? If it is full or clogged, then maybe oil is blowing past it and into the carbs?
 
I assume that the leaking during refill revealed a bad valve cover gasket and that you have replaced the gasket.

If the separator is clogged nothing will pass. Try just blowing through it, should be no real resistance.

You seem to have symptoms of a crankcase pressurization issue. When you start the engine tomorrow, leave the valve cover filler plug out and just put a rag over the opening to catch mist. Then with the engine running smoothly feel for air coming from the filler. Should not be much at all. If it feels like a breeze or powerful pulses then you may have a holed piston.
 
I'm not sure what combination of things I did made this happen, but this morning, the smokescreen had dissipated. I had one large cloud on my first launch after start up, and then nothing. There's still a touch of blue here and there, but that's not unexpected. I don't know if it was the cranking down on the head, the carburetors, or readjusting the valves that was the culprit.

Before I took the car out, I decided to degrease the engine so I could see where any oil was coming from. After the test drive, I still have one small leak on either side of the valve cover gasket towards the rear. I'm either having poor luck or I'm using poor technique with valve cover gaskets. I tried the VB silicone gasket. The one that is on there now is the BPNorthwest cork gasket.
 
Sometimes the valve covers get warped from someone over tightening the bolts or prying up on the flange to remove it. Check to see that the flange is straight and flat with a straight edge or ruler. Everyone has their preferences, but I have always used Permatex tack and seal compound on just the cover side of the gasket and nothing on the head side. I've never had one leak. I don't like silicone in combination with a gasket.
 
yeah, be sure the valve cover is flat where it meets the head. If it's distorted from over tightening, it'll leak.

I glue my valve cover gasket to the valve cover (using contact cement). Then, when you attach the valve cover to the head, the gasket doesn't move.
 
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That's always been my trick, glue the gasket to the cover first.
 
Same here and I keep a couple spares stretched over the outside of an old valve cover. They do still have a tendency to shrink and sometimes begin leaking.


Kurt.
 
Ok...got it. I just glued the gasket to the cover, and I can see what's been happening: The gasket wants to take the shape of a dog bone instead of the valve cover. It took me a while to get the gasket to straighten out while the glue set up. Do you put anything between the gasket and the head? RTV? Grease?
 
you still have cast iron heads? I got rid of mine years ago. got some aluminium heads. cast iron were easy to crack.
 
I use grease on the gasket where it will contact the head. Hopefully that will keep it from sticking to the head so that you can remove the valve cover without damaging it for future maintenance.



Kurt
 
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