Yes, but down a hole inside that cavity. Image Unavailable, Please Login You can't see the hole due to the picture angle, but it's "beneath/under" the head stud. I've marked the circle above where it is, inside the cavity. It's at least 10" deep, according to the magnet-on-a-line I've dropped down the hole (the magnet seemed to bottom out on something after about 10".)
Update: I pulled the oil pan again (great, a brand new $22 gasket in the trash) and ran a long line down the hole. The line exited into the oil sump. So the nut could end up down there. Bad news: there's no 10mm nut in the oil pan. Which makes me think it dropped somewhere above. Possibly right into the crankshaft area? Starting to think my car may become a barn find in 30 years.
Not to doubt you but you’re absolutely sure the nut went down that drain hole and is not hiding up there around the valves or head stud? Here’s a picture I found of the bottom of the block, looks like it pretty much has nowhere to go other than the pan if it went down that hole. Picture
Another picture. See how the transmission forms a ledge just under where those drain holes from the 1-4 head come out?
getting my scope as far down that hole as possible all I can see is that it apparently exits just above the top of the gearcase and it doesn't look like there's much of a gap. Maybe the nut is sitting there edgewise. Try running a fishtape all the way through or possibly a piece of bent wire from the bottom to scrape along the top of the gearbox. The nut should fall through to the pan so long as the gap is big enough. Good luck I'm sure you'll get it one way or another.. Image Unavailable, Please Login Image Unavailable, Please Login
Wow, cool. First, thanks for the pics. Incredibly helpful. No worries wondering if it really fell down that hole. After I pulled the pan I started wondering if I'm crazy... wish I was. But it was clear to me when it did, and the cavity is easy for me to see in that it's not hiding there. Wish it were... There's a half cylinder sheet cover that the oil tube connects to above the pan. Like a coffee can cut in half. There's a small gap just beneath the drain hole, but not much. Based on your pics and thoughts, I have the same conclusion - being stuck/wedged on that ledge. Going to focus my efforts on that particular haystack and see if the needle appears.
Wow, cool. First, thanks for the pics. Incredibly helpful. No worries wondering if it really fell down that hole. After I pulled the pan I started wondering if I'm crazy... wish I was. But it was clear to me when it did, and the cavity is easy for me to see in that it's not hiding there. Wish it were... There's a half cylinder sheet cover that the oil tube connects to above the pan. Like a coffee can cut in half. There's a small gap just beneath the drain hole, but not much. Based on your pics and thoughts, I have the same conclusion - being stuck/wedged on that ledge. Going to focus my efforts on that particular haystack and see if the needle appears.
Probably won’t work but have you tried a strong shopvac and creating a seal around the nozzle? maybe that will at least cause that nut to make itself know.
Just wanted to say your doing a great Job, and I'm hoping you find it easily and move on With the servicing
I've put it aside for a couple of days. Have a lot of studying to do (taking an ASE test tomorrow), and decided I needed to focus on books for awhile without anger floating over my head. I'd thought about a shopvac, but didn't think it would create enough pressure (like a true high-pressure shop air system would)... but ya know, it's sitting right next to the car. Worth a shot. I'm also going to try attaching a small cotton patch to the bottom of the inserted line (from the bottom of the pan) and pull up. Hoping if it's in there, ya know - dislodge it. Thanks so much. I really appreciate everyone's encouragement and suggestions.
Take your air gun and blow like crazy through that hole, moving continually. That's how I found my 4th dimension travelled A/C rubber bushing after an hour. Just be certain that you have a blanket or something to catch it when it goes whizzing away.
Taking a break is a good idea, you don't want to be doing this when you're mad. Since I can currently clearly see the drain passage on my engine I would say, given it's diameter, that it is highly unlikely the nut would be hung up half way down. My guess is it is sitting on top of the gearcase and there may not be enough clearance for it to pass through the gap between the bottom of the drain passage and the top of the gearcase. If that is the case then there is a possibility that just leaving it there would be an option. Since you have the sump open try pouring some oil down the drain and see that it's not restricted or plugged. The last thing you want to do is get something else stuck in there (like a wad of cotton)
From under the car (oil pan off), and looking up, I can see a bronze-colored curved cover. Parts diagram calls it a Protection Cover. I've highlighted in yellow. I'm wondering a few things: 1. The area in red, above this cover, looks like gears... and... stuff that moves (can't tell, the cover is in the way). I'm worried the nut could have dropped with a weird bounce, and be on top of whatever is in that area (and kill something). It could also be sitting on the cover topside too, i guess. 2. I have considered removing the protection cover, due to this. 3. It seems if I remove the oil feel nuts (highlighted blue) and the 2 nuts in the diagram (highlighted green), the cover may drop down. 4. Or, there may be FOUR cover nuts (green), and only 2 are accessible - and thus, without full engine removal, you can't get them out. So - thoughts on all that? Image Unavailable, Please Login
Updates: 1. I was able to run a line from the top of the block, through the hole, to the floor. With wire, I fastened a tiny ball of kevlar fishing line to the low end. Sort of a hook+wad arrangement, larger than the inside of the nut. 2. Pulled this back UP through the block, to see if it would drag the nut up and out. The wire pulled without a lot of resistance. Repeated the process 2-3 times. The nut never appeared up top, nor dropped out of the bottom. 3. I'm now fairly confident the nut is no longer in the drain hole, but due to angular obstructions I can't borescope the tube. 4. If the nut IS in there, I don't think it's coming out. 5. I poured oil down the tube. It drains as you would hope. As long as there's nothing inside that oil case above the protective cover that the nut could bind into and destroy (biggest concern), I may just have to seal it all up and forget about it. I really don't see many other options at this point besides pull the entire engine out and take the whole thing apart. I'm willing to do that if I have to, but if the nut cannot be possibly in a place that causes damage then I won't go that far.
Friday Evening Update: The wayward nut was given a hard stare and tossed in the trash for bad behavior; God was given a quick thank you. 2 new Grade 8 nuts are now keeping Cap #2 happily in place. A new oil pan gasket to replace the new/newly-ruined oil pan gasket arrived from Ricambi, along with new studs to replace all the ones I had over-torqued and potentially messed up. Fasteners are one of those things that shouldn't always be reused, and the studs were prime candidates for replacement. 9 of them went in with little effort. The 10th felt ok going in, but after about the 4th thread I could tell it was going far off-angle. Whether the bad torque is responsible or just bad luck, that particular journal-cap hole is cross-stripped. I'll be repairing that with a helicoil this weekend. I've doing a couple helicoils in the past with steel parts, so hopefully the aluminum will be easier to drill accurately and install. Helicoils are structurally superior to the original aluminum block itself, but taking a drill to a $25,000 engine will be a bit unnerving. As an aside: I suppose I could have only mentioned the successful points in this service project, but decided to include all the mistakes and bad events as well. Many perfect plans often don't execute perfectly, and I hope by mentioning the bad stuff - others who pick up a wrench will remember my pitfalls and hopefully avoid them.
So where was the bad nut and how did you retrieve it? Don't leave us hangin' like this... As for the helicoil be careful and take your time. Do you have a drill cup or something to ensure you're perfectly square? If this is a journal cap you need to be sure it's right.
This is sort of a guess: I was taking a break from "work" and cleaning up my tools that were laying all over the place. You know, let's take a moment and clean up and get re-centered and re-organized. During the process, I found the nut in the middle of the trunk as I was removing a couple tools. I'm 110% confident it wasn't there yesterday afternoon, before I did my final "yank the drag line hook/wad combo" thing. There were exactly 2 8mm nuts in the trunk for the past week. So, my guess is that on one of my final attempts, it popped out of the hole at the top and landed in the trunk. Given the dimmer lighting conditions late last night, I guess I didn't see it pop out (and was rather tired and grouchy) and didn't notice the success. I've been judicious with bagging and labeling all the hardware, and had accounted for every single 10mm nut that was removed from the car - including 10 discarded nuts in the trash. I can even see the circular wear pattern from the black washers, and it was slightly oily. So... yeah, that has to be the one. I'm going to tape and cover everything for debris. Possibly tape 2 t-squares to the block to ensure I'm going in straight. I've also found an angular power drill guide (sort of a standalone chuck attachment that makes a handheld drill behave like a drill press), which I may purchase. Only one shot to get this right, I know. Get it perfect, and it's better than perfect. Get it wrong, and ... lots of tears.
As I'm sure everyone is on the edge of their seats (ha)... engine drilled, helicoil installed, stud inserted, and all 20 cam journals back in their happy place. Time for some Indian food to celebrate. Image Unavailable, Please Login
Doing all this stuff makes you and your car "one". Its a great feeling knowing that you did it all. (Yes, that was really over kill with all that sealant on some of the gaskets you removed.) Have done belts and cam seals a couple of times on my 308. The last time I had to remove the intake manifolds to replace the gaskets there also. Well done!!
New valve gaskets in place, with proper RTV dabs applied to the o-rings. Waited an hour for the RTV to cure. Set my torque wrench to 6.5 ft lbs, and began carefully tighten down the valve cover in sequence. And the valve cover cracked. Image Unavailable, Please Login
