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i have replaced my valve cover gaskets but decided to replace my intake manifold gaskets so waiting for parts. But I was wondering if you could answer another question. I noticed that there is a whole in my head near the number 3 cylinder that must go to the crankcase. There is another one in the front side near cylinder number 1 but it has a plug in it like a freeze plug. Is there suppose to be a plug in the same place that has fallen out or corded away or something else? Seems like that is my oil leak and is covering my spark plug so replacing valve cover gasket and spark plug seals won’t keep this problem from happening again. WTF,
i have replaced my valve cover gaskets but decided to replace my intake manifold gaskets so waiting for parts. But I was wondering if you could answer another question. I noticed that there is a whole in my head near the number 3 cylinder that must go to the crankcase. There is another one in the front side near cylinder number 1 but it has a plug in it like a freeze plug. Is there suppose to be a plug in the same place that has fallen out or corded away or something else? Seems like that is my oil leak and is covering my spark plug so replacing valve cover gasket and spark plug seals won’t keep this problem from happening again. WTF,
can u post a pic? Could be a freeze plug but im confussd if its in the head or block. You said it goes to the crankcase?
if you’re missing a freeze plug, youd dump all your coolant on the ground
Hope these photos are clear. The first one is the spot on the drivers side head by number 3 cylinder where there’s a hole that looks similar to a freeze plug but is not, it goes all the way down to the crankcase and allows oil to foul the spark plug. The second pic is of the freeze plug in the front of the head by cylinder number 1 that has the same diameter as the spot in the back of the head by the firewall. The hole/spot is not for a freeze plug, which I know because after micing the hole it does not have enough depth. Also, the back hole has a bottom to it that may have some threads in it. I very much appreciate your help my jag runs great but found this hole/spot was causing a mess fire and each time I cleaned the oil from around the boot it stopped for a while. I purchased the car at an auction for $1000 with only 70,000 miles on it but am finding out why the grandson of Nana threw away the car. Lol!
The first one is the spot on the drivers side head by number 3 cylinder where there’s a hole that looks similar to a freeze plug but is not, it goes all the way down to the crankcase...
Are you positive the hole goes all the way through the head? Poke a wire in there? Look at this cylinder head on eBay:
If that big ugly link works, check out the pics. Look at the picture of the bottom, showing the four valves with the spark plug in the middle. Your mystery hole is maybe 2 inches max from the spark plug, and would be over the piston. There's no space between the cylinders for such a hole to reach the crankcase. I'm thoroughly confused.
Thanks for the input and when I put my finger in the whole there is oil on it so where else would the oil come from? However you gave me an idea so I looked at the other side, the drivers side and see a plug of some kind there. Here’s a picture!
This is a total view of the driver side head from EBay. See the plug or something on this head? It’s missing on mine.
Last edited by WendellB; Jan 10, 2021 at 09:35 PM.
Reason: Adding some photos
No idea of the purpose of those holes and plugs, and why your engine is missing a plug. The picture you posted clearly shows the holes are over the piston, so there's no way they could extend through.
Have you poked a wire in there yet? That should provide a definite answer. The hole has to have a bottom. The oil you found would have come from a leaking valve cover gasket, filling up the spark plug well. Clean it up and fit a plug in this hole if desired. Even RTV would work. Or just leave it. It's not critical at all.
Let's suppose that hole was somehow open at the bottom to the crankcase, and oil could splash up from underneath. When the engine was off, any oil in the hole would quickly drain back down. There's no way oil would sit there unless the bottom was closed off. This means oil would have to get there from another path, and nothing makes sense except via the valve cover gasket around the spark plug well.
My '02 V6 has oil collect around #3 spark plug. A new gasket is on my to-do list, but I'm lazy and keep putting it off. The leakage rate is so low, it's not a huge concern. Every few months, I pull that coil and sop up the oil with a paper towel. I clean everything up with electronic cleaner spray and I'm good to go for another half year or so. Ten minutes tops, maybe.
