mysterious oil leak
#1
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mysterious oil leak
I'll be darned if I can find where this is leaking. I've lost several quarts over the past few months though and don't drive it enough for it to be leaking while I'm driving. Right now there's too much oil spread around to be able to track down to one place but I'm hoping someone will be able to give some hints ... Any thoughts/ideas would be much appreciated. It's only leaking on the driver's side. it has been for as long as I know. It isn't bad enough to be really concerned but enough that I want to find it so I can clean it up.
#3
Safety Car
Originally Posted by TEP061
I have an idea of what it is, but the first step to solving a mess like that is clean the area of all oil. Then you'll be able to monitor whats going on.
AND replace the valve cover gasket on that side. Better yet, replace both sides.
#4
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I'm going to clean it shortly. I was hoping to get some ideas to watch for so when I did get it cleaned i'd be in better shape (or know places to clean particularly well). My grease remover was dead today.
I did replace the valve cover gaskets on both sides recently. it's leaking from below the valve covers. I did that as an easy first fix.
it appears to leak primarily while sitting. Seems like something low in the engine. I'm just not sure where.
I did replace the valve cover gaskets on both sides recently. it's leaking from below the valve covers. I did that as an easy first fix.
it appears to leak primarily while sitting. Seems like something low in the engine. I'm just not sure where.
#5
Race Director
Assuming it is not your valve covers, (it looks like it is, even though you changed them, you may have not used new cork gaslets, or your covers are warped), i would look at your oil pressure line where it goes into the block.
Doug
Doug
#6
Race Director
Looks like valve covers to me also. Probably also need to check the intake seal at the rear but a leak there would not migrate around to the exhaust ports.
Dan
Dan
#7
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Oil pressure line is small tube that goes in on driver's side of distributor, correct? Anything special about that? It is tight but what else do i check for? Any way to tell if valve covers are warped? I bought gaskets from AutoZone a couple of years ago. Just asked for gaskets for a 327. Anything I should specify or look for to replace them again?
Thanks for the suggestions!
Thanks for the suggestions!
#8
Race Director
Originally Posted by blueray
Oil pressure line is small tube that goes in on driver's side of distributor, correct? Anything special about that? It is tight but what else do i check for? Any way to tell if valve covers are warped? I bought gaskets from AutoZone a couple of years ago. Just asked for gaskets for a 327. Anything I should specify or look for to replace them again?
Thanks for the suggestions!
Thanks for the suggestions!
Try not to get your distrib wet.
Take a couple dry towels and a screw driver to take the distrib cap off and dry out the inside if you do get it wet. You will know if it is wet if your car doesn't start.
Look at the oil line as you described after you wash the car, then look at it once you get home, if there is oil visible, you have a leak there. Get a new oil line assembly or try to tighten the one you have.
Cork gaskets, not neoprene.
A straight edge on the long side of gasket surfaces (off the engine, underneath) will tell you if it warped.
Doug
#10
Melting Slicks
Check your rear intake gasket as Dan said. On my '63 it was almost completely squished out in one spot. It was not only running down the sides of the block, but was going between the block and the bellhousing and making a heck of a mess.
Rich
Rich
#11
Last time i had a leak like that i thought it was my valve covers. I replaced the gaskets and something still kept leaking. After looking and looking i finally figured out that it was coming from the exhaust port. Turned out that somebody at the machine shop forgot to put the umbrella seal on that valve and so oil was leaking down into the cylinder and out around the exhaust. however, this was also combined with a fuel pump leak that made a big mess. I am not saying it is your valve, but if you are taking the valve covers off to replace the gaskets anyway, get a flash light and take a look to make sure the umbrella seals are there and ok. It could be something more serious, but hopfully its just a gasket.
#13
Mine has a slow leak from the oil pressure fitting, causing oil in similar areas. Fortunately, it is very slow. Worth checking before you do anything drastic. If you find a good tool to tighten it up, let me know.
#14
Originally Posted by 65Tuxedo
Mine has a slow leak from the oil pressure fitting, causing oil in similar areas. Fortunately, it is very slow. Worth checking before you do anything drastic. If you find a good tool to tighten it up, let me know.
#15
Team Owner
Clean up the area. Get some fluorescent dye (4 oz, $4.00) from your GM dealer, add to oil, borrow a black (UV) light, drive car, shine black light on that area. Origin of leak will be readily apparent.
#16
1. You have a spin on filter conversion- they are famous for leaking.
2. If you have new valve cover gaskets, I assume you put them on because of the leak? Did that change the leak at all? The gaskets sit on a ridge at the edge of the head- can you feel the gasket sitting out at the edge all the way around the valve cover?
3. Check to see your intake bolts are torqued correctly- how long since it was off? Do you have a rubber gasket at the back of the intake and can you see it or feel it all the way across?
4. Have you pulled the plugs- are any of the plugs fouled with oil?
5. Most times, the oil is leaking while the engine is running and creating oil pressure. The oil on the outside is then blown around while driving and it is hard to find the leak because everything is covered with oil.
Clean everything with a rag to remove all visible signs of oil at the seams where it could be leaking- valve cover, back of block at the intake, the oil pressure line, and the spin on filter. Then let it sit for half a day or so and see if anything leaks out without starting the engine. If nothing happens, start the car and let it run for 3 or 4 minutes to build up a bit of oil pressure, then check again for visible signs of oil. Doing this should eliminate some areas and help you find a leak.
Don
2. If you have new valve cover gaskets, I assume you put them on because of the leak? Did that change the leak at all? The gaskets sit on a ridge at the edge of the head- can you feel the gasket sitting out at the edge all the way around the valve cover?
3. Check to see your intake bolts are torqued correctly- how long since it was off? Do you have a rubber gasket at the back of the intake and can you see it or feel it all the way across?
4. Have you pulled the plugs- are any of the plugs fouled with oil?
5. Most times, the oil is leaking while the engine is running and creating oil pressure. The oil on the outside is then blown around while driving and it is hard to find the leak because everything is covered with oil.
Clean everything with a rag to remove all visible signs of oil at the seams where it could be leaking- valve cover, back of block at the intake, the oil pressure line, and the spin on filter. Then let it sit for half a day or so and see if anything leaks out without starting the engine. If nothing happens, start the car and let it run for 3 or 4 minutes to build up a bit of oil pressure, then check again for visible signs of oil. Doing this should eliminate some areas and help you find a leak.
Don
#17
Burning Brakes
I agree with Don on point #1. and it will drip/leak with eng off. Clean eng and clean cardboard under eng, check for static leak.
let us know
rene
let us know
rene
#18
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I have cleaned and found that at the least I have a crack on the valve cover around the bolt. Engine was hot so I haven't been back under to see if there are any other leaks. Thinking I need new valve covers. Ones that tempt the the most right now are made by Edelbrock
http://store.summitracing.com/partde...5&autoview=sku
I don't have the stock heads (70 Z28 heads for unleaded gas) so I'm not worried about keeping it stock. I do have the original heads and valve covers boxed up if I ever want to go that way.
Any thoughts on valve covers? I do have the finned aluminum now. Anyone have just one they want to get rid of?
Thanks
Bryan
http://store.summitracing.com/partde...5&autoview=sku
I don't have the stock heads (70 Z28 heads for unleaded gas) so I'm not worried about keeping it stock. I do have the original heads and valve covers boxed up if I ever want to go that way.
Any thoughts on valve covers? I do have the finned aluminum now. Anyone have just one they want to get rid of?
Thanks
Bryan
#19
Le Mans Master
post up in the parts section, lots of traffic there. These covers come up often on ebay too, but usually in pairs.
As for your leak, my money is squarely on an intake manifold gasket failure, rear corner.
As for your leak, my money is squarely on an intake manifold gasket failure, rear corner.
#20
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check the front and rear intake manifold for a gasket. If it has a gasket, that is most likely your problem. They rarely seal very well and I learned that the hard way. Easy fix though. just buy new gasket set, throw away the front and rear seals and use correct RTV to seal front and rear with about a 1/4" bead. You can find tons of information how to do this with Google search. For some reason the front and rear of intakes don't match up well with blocks.