Ever just have one of those weekends where it seemed like everything that could go wrong does? I'm just coming off one of those
In six months I'll read this post and be able to think objectively about it, but tonight all I can do is think of various four letter words...
On Friday I had planned to be at the track, but after finding the major oil leak in the engine last weekend, and not finding any simple solutions by Monday night, that plan went out the window. Instead, with my day off Friday I resolved to get the leak fixed. On Thursday I stopped into my friend BradFORD's shop, and my friend Tom lent me some engine oil dye, and also a UV penlight, to help track down the leak. Thursday night I got under the car and cleaned everything off with solvent so it was nice and oil free. I also bent the block plate back towards the flywheel somewhat, so that I had at least a very narrow view of the back of the main cap. (It dawned on me during this process that the portion of the block plate around the main cap isn't really necessary, and I think that the next time I have the block plate out, I will cut this section away).
I dumped the dye in the dry sump tank, then started the engine and ran it for 30 seconds, then shut it off and crawled back under the car to look for any signs of the leak. After the fourth 30 second run, I saw a drip running down the back of the main cap. Looking up into the narrow gap between the block plate and the cap though made it difficult to identify the source of the drip. I thought it might be coming from the junction of the cap and the block, but it was really tough to tell for sure. I got back in the car and ran it for another 30 seconds, but when I looked again there was just too much oil down there to identify exactly where it was coming from. This is a very serious oil leak, with 3-4 drips per second coming out at the back of the engine once it gets going.
After seeing the drip down the back of the main cap I decided that I had no choice but to replace the rear main seal. Friday morning I got under the car and started disassembling. With the front suspension on this car, the entire front suspension assembly has to come out to get at the oil pan. Here's a picture of the front suspension removed, and sitting out in front of the car:
I drained all the oil out of the dry sump and the pan, and saved it because it was new, and I wanted to re-use it because it had the dye in it, and it would be easier to check for leaks with that oil. After disconnecting the dry sump lines, I pulled all the pan bolts and removed the pan. After getting it off I took a look at the gaskets and the engine's oil pan rail, and noticed with some surprise that all along the rail there was evidence of sealer and gasket material stuck to the rail, except between the two oil pan bolts that went into the main cap! There didn't appear to be a good seal to the gasket at that point. Maybe this was part of the leak issue?
By this time, laying under the dripping engine and the dry sump lines, I was pretty well soaked in oil; this is always a miserable job. But as long as I was under there I figured I'd finish the job, so I pulled the two #5 main cap bolts and got ready to pull the cap. On the Shelby block you have to use a slide hammer to get the caps off, but when I tried to fit my slide hammer it hit the floor; it was too long to use in this position. I had to cobble up a makeshift slide hammer to get the cap off. After I had the cap off, I grabbed the top half of the seal with a needlenose pliers; it came out easily.
Finally out from under the car, I inspected the cap and seal closely. It appeared that I had a good seal along the sides and parting surface of the cap, because there was evidence of sealer in these positions. The main bearing looked fine, and so did the main seal halves. No real evidence of a problem here. Hmmmmm...
I let the engine drip dry for a few hours while I did some other work on the car, and then I started the reassembly process. I made sure to get the pan rail and windage tray nice and clean, free of old sealer, and then spent some time getting dripped on again to get the pan rail cleaned up. I put the rear main seal in the normal way this time, and clocked the seal in the block just a little to offset the seal gap from the cap gap. When I installed the cap I put some sealer on the block surface of the cap, as usual. This time I had decided to try the side seal method that Ross described in another post, so after torquing the cap I installed the side seals with them lubed up with plenty of sealer, and then drove in the nails. Seemed like it worked just fine.
Finally I got the pan and windage tray installed, using a pair of SCE gaskets that I had ordered this week. It had occurred to me while cleaning the pan and windage tray that the area on the main cap where there didn't appear to be sealer and gasket residue was exactly the spot on the Fel-pro oil pan gaskets where they fold it in half for packaging. Maybe that had something to do with the issue, so the SCE gaskets (which don't come folded) should eliminate that possibility. By around 11:00 PM on Monday I had the oil pan re-installed. I decided to let the sealer dry overnight, then hook up the pan and fill the engine with oil for the test in the morning.
Saturday morning I was back out to the shop by 9:00, and was ready to test fire the engine by 10:00. After firing the engine up I watched for a couple of minutes, and no sign of oil. Great! The phone rang, and I answered it and talked for a couple of minutes, then cam back to the car and - oh no - another huge puddle of oil in the same spot as before
Well, crap. Everything had seemed to go together pretty well; why was it raining oil under the car? I checked again up top, to make sure that there was no oil leaking from the valve covers, heads, or intake manifold, but it was dry up there. I cleaned off the area under the back of the engine, and went back in with the UV light after running the engine for a minute or so, and this time I didn't see a drip down the cap, but I did see some that appeared to come from the sides of the cap. But it was difficult to tell for sure; there just isn't much room up there to see what is really going on.
At this point I decided to call a friend of mine who assembles a lot of FEs, and see if he had any suggestions. His name is Kurt, and after talking this through with him on the phone he volunteered to come over and take a look. Once he got there I ran the engine again while Kurt watched from under the car, and he agreed that it looked like the rear main and/or the cap to block interface. So, we decided to do it all again
Sparing the gory details of the oil draining and dissasembly, we finally took the rear main cap off again. I looked closely at the area where the side seals were, and there appeared to be a good track of sealer there, and also at the cap/block junction; disassembling this I would not have expected to see a leak. Again the main seals looked fine, and this time there was no evidence of sealer missing at the center of the main cap. It just did not look like there could be a leak here.
Kurt and I took excruciating pains to make sure that the new top seal went in properly, and that the block and cap were perfectly clean and prepped before installation. This time I did not clock the seal halves like I usually do, but put them in straight because that's the way Kurt likes to do them. Also we didn't use side seals; we filled the side seal groove in the cap with black Permatex RTV, and then after the cap was installed Kurt pushed into the cavity with a round punch and forced sealer out between the cap and the block, so that we had a bead of sealer coming out the back. I've done the same thing in the past, using the side seals to force the sealer out.
Kurt left around 6:00, and after a break I came back out to the shop to put the oil pan and windage tray back on (again
) After cleaning everything up (again!
) I decided I would lay a straight edge across the panand make sure the surface was still flat. Boy, was I surprised what I found. The back left corner of the pan rail dipped way down, out of line with the rest of the pan rail by a good 1/8"! How the heck did that happen? It wasn't that way when I assembled the engine, that's for sure. I was left with the conclusion that the heat cycles on the dyno had warped the pan, and when I uninstalled it the warp appeared.
Due to the design of the pan it is not possible to hammer this part of the pan rail into shape, so Saturday night I stuck it on one of my CNC machines, and started re-machining the pan rail. Turned out I only needed to take about .090" off to get it all squared up. I got about half way done and the CNC machine quit; it said it had run out of air. I checked my compressor, and sure enough the circuit had blown and the compressor was off. I tried to reset the breaker, but it just kept tripping. So no air compressor, and I couldn't finish the CNC work on the oil pan.
This pretty much just capped off a rotten day. Earlier in the day UPS had delivered a package to me. But the package was one I had shipped to a guy in Connecticut with a 351C intake in it. They delivered it back to me instead! I called UPS and they basically said OOPS, drop it back off at the UPS store. Then halfway through the day my daughter had a personal crisis that required a family conference, with lots of wailing and gnashing of teeth. When the air compressor quit, I'd had it. I shut off the lights and went to bed.
Sunday morning I was back out to the shop for more punishment
First I flipped on the air compressor breaker, and it fired right up; I think it is getting sensitive to the heat or something, and just needed some time to cool down. I spent the next hour finishing off the CNC work on the oil pan; while I was doing this I was thinking about the leak, and if this could have been the cause. When I first saw this issue I thought, aha! But now I wasn't so sure; the leak had not appeared to be coming from the area where the pan was warped. Plus, the bolts should have pulled the pan up into position when it was installed; its not totally rigid in that area. In any case, making the oil pan rail flat couldn't hurt, so after I got done with that I installed the pan. During this process though I ran out of my favorite sealer, Ford TA-31. I rummaged around in my sealer box and found an unopened tube of Loctite grey sealer, which I have used successfully in the past, so I finished off with that. By 11:30 I had the pan installed. I went back in the house to grab some lunch and let the sealer dry before test firing the engine.
At 1:30 I went back outside. First I crawled under the car to make sure the sealer had set up, and was surprised to find that it was still not skinned over. That was odd. I read the sealer tube, and it said that it should skin in an hour, and be completely cured in 24 hours. Hmmmm.... I busied myself with some other tasks on the car, and then at 3:30 I crawled back under the car to check the sealer. Still wet, and not skinned! I grabbed my heat gun and hit one section of the oil pan where the sealer was pushed out with heat for a couple of minutes. The stuff was still not skinned, even after that!
Well, I sure wasn't going to try to fire up the engine with the sealer not drying. I decided to try an experiment. I dug a bunch of RTV sealer out of my sealer box, including a couple more tubes of the Loctite stuff, and put some beads on a piece of cardboard:
After another hour I checked again. All three beads from the three different tubes of the Loctite sealer were not skinned, and all four beads from the other four tubes of sealer were nicely skinned over.
So, as I type this, the sealer has still not skinned over, and I haven't yet test fired the engine to see if it still leaks. I've spent three solid days on this problem, with no resolution yet. And, frankly, I'm not optimistic about the results of the next test. In both dis-assembly and re-assembly procedures, I didn't find the smoking gun I was hoping for on the leak. I'm starting to become pretty convinced that it is coming from the back of the block somewhere, and that next I'm going to have to pull the transmission to look back there. It could be the cam plug (although I have that held in place with some screws and washers), and it also could be one of the five plugs in the back of the block. I guess when the sealer finally cures I will find out. Drag Week starts five weeks from today. Still waiting to make it to the track...
