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finally drove my Nova a good bit. to the mechanic and back. each way is about 10 miles on the highway. so i was doing about 60 mph. oil leaks. some up on the intake manifold around bolts. so i think they need some permatex. but about a day later I looked underneath and saw a lot more oil. the mechanic who did not address this problem, said the intake could be warped. he did straighten the valve covers so they would be flat and installed new gaskets so those aren't leaking. or are they. this engine is old. and i don't know the full history. so the rear main seal could be done for. check out the photos and I am open to advice or thoughts.

I did pull the car straight back to clean up the oil and get the photo.
 

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Based off your exhaust pipe, I say valve covers. I am sure your rear main seeps as most do at age. I see a frost plug is leaking too, neat.
 

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Did they replace the intake gaskets, did they use silicone at the front and back? I remember most leaking at the bolts, in the middle if silicone wasn't on the threads. Make sure your PCV is good, will force oil out if not.
 

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Mike - 74 Nova Baltimore, MD
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First step (in my opinion) is to give everything a good cleaning and take a few short drives to see where/if the leaks start forming.
If your fan is blowing it could scatter oil all over leading to you chasing your tail. Narrow the scope first. :D
I agree with BillyT. Another thing that I do to help find the origin of engine leaks (after cleaning all of the previous visible leaks) is to take some paper shop towels and shove them into places just below the valve cover gaskets and intake manifold seals - be sure the engine if not running while completing this step. This trick helps eliminate upper engine leaks moving further down the line.... which in turn makes the troubleshooting more difficult.

Now start your engine and drive around for a few minutes... but keep your speed slow. Recheck for leaks. If the paper towels show traces of a leak, the leak is most likely coming from above the towel. If traces of a leak are still shown on the lower portion of the engine (and the paper towels are dry), the leak is probably originating from a lower point than where the paper towels were inserted (head gasket, timing case cover gasket and/or balancer seal, rear main seal, oil pan gasket and/or lip seals, etc).

Another place to look for oil leaks is around the fuel pump... and on the engine block just in front of the fuel pump. You will notice two bolt holes (as shown in the photo below). The top hole is drilled and tapped thru the block and should have a bolt installed that has been coated with some type of thread sealer.


P.S. I also noticed what looked like coolant on the top of the oil pan rail.
 

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I agree with the posters about starting with your engine clean and dry, which will take a little work. A dye is sold that you put in your oil that will run through the engine. With a UV light (cheap, also online) you can see exactly where the dyed oil is seeping from and at what rate. A lot of shops use this method.
 

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Based on the photos, it looks like everything is seeping, and a few more things are leaking.
Rear main probably leaks, but I'd suspect front cover, rocker covers, and/or oil pan for dispersed drippage like that.
 

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leaks

Is this a six? Looks like it. The rear seal leak is obvious as it is around the tranny more as you drive it leaks backward. I don't see it. Clean the engine up and run it and look around. Many of your gaskets look old so it may be time to redo some of them. Pan gasket and valve cover is the normal ones to leak but I had a gasket that leaked for 5 years until I found it at the front of the pan around the pulley area. Replaced all of this and no more. Had rear seal done and tranny seal done too. No more leaks except valve cover gaskets tend to be wet most of the time despite changing and not over tightening. Best thing to make you not worry is to do them one at a time and eliminate each one. You also have a coolant leak so that is not good as it is a sign of rust on either a freeze plug or god forbid the head. Good luck.
 

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Check the valve cover breathers, when they get old they leak oil at higher rpms like highway driving and will look like valve covers and a intake oil leak.
 

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Discussion Starter #11
if it were the breathers, wouldnt there be some oil on top of the valve covers?

this is a 1969 350 V8. all the gaskets are new. I may need to take it to a mechanic to find out if it is worth saving. i dont want to pour a lot of money into an engine that isnt viable. if that coolant is an easy fix, i would keep it. but if that means the engine needs to go to a machine shop, i would rather get a different engine and a 700r4.
 

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If you have a mechanical aftermarket oil pressure gauge you likely have one of those cheese-ball compression fittings next the distributor. The heat and the vibration can get to it and the nylon tube.
I'd look closely in that area before I gave up.
 
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