The best part of the process, though, is the feeling of having just ordered a part. At that point, the puzzle has been solved, the project is back on track, if somewhat delayed, and all you have to do is sit back and wait for the part to arrive. Then the part shows up and it's like Christmas. Then the part doesn't fit, and ... well, let's not think about that right now.
When I ordered an oil pan, I sorted by my engine type, my car type, and by orange paint, because I wanted it orange, and I didn't want to have to paint it. I also picked this specific pan because it has a custom-fabricated enlarged sump with an internal baffle to control sloshing and keep the oil pickup submerged. That's all "race car stuff" that I don't really need at all, but which I think is neat, and is not prohibitively expensive, so I'm going to have it.
Unfortunately, as I mentioned in the last post, I had to pull the engine back off the chassis due to an interference between the oil pan and the steering linkage. The larger sump (which I don't really need) interferes with the center drag link in the steering linkage. According to the information listed on Summit, the pan was supposed to fit my application, but when I put it all together, there was just a very slight interference when the wheels were turned all the way to one side.
Part of the problem was probably that I had installed aftermarket control arms, and a disc brake conversion kit which required modifying the steering arms, and all of this may have contributed to changing the geometry of the steering linkage. It may have been further complicated by the fact that the steering box on the '65 Impala is mounted behind the front wheels, which puts the steering linkage between the oil sump and the chassis crossmember. Bertha, my 1972 Monte Carlo, had the steering box mounted in front of the front wheels, which puts the steering linkage in front of the crossmember and nowhere near the oil sump. Same goes for a Chevelle, which is probably a much more popular application than a 1965 Impala, so less likely to generate complaints to the manufacturer of the pan.
In fact, 1965 Impala projects seem to tend to be of the type that get either a stock oil pan, or maybe a chromed stock oil pan. It's possible I might be the first person to ever put this particular style of oil pan on a big block in a 1965 Impala. Who knows. In any case, the oil pan and the center drag link want to be in the same spot, and that's no good.
So, I pulled everything off the chassis and put the engine back on the stand. As received, without modification, the front of the sump was pretty much just a vertical wall. I didn't really get any pictures of it before modification, but you can kind of see it in this picture from the Summit website:
The interference was so slight, I originally thought maybe I could just bend the front of the sump to form a "pocket" that the centerlink could tuck into when the wheels were turned. I didn't want to cut up the pan and then have to get it welded back together if I could avoid it, so I decided to try smashing it with a hammer, instead.
Before I pulled everything off of the chassis, I marked the vertical centerline of the centerlink on the front of the oil pan. After I had everything apart, I took a section of an old jack handle and used a couple ratchet straps to clamp it on to the front of the sump. I put some masking tape on, too, in a foolish hope that maybe it would keep me from messing up the paint job too bad.
Once I had that all set up, I pretty much just started whaling away on the jack handle with a hammer. The next couple pictures show how the front of the sump started to cave in to form the desired pocket. I tightened the ratchet straps as necessary to hold everything together.
Of course the paint was pretty messed up, so I did have to re-paint the pan at that point. Good thing I ordered an orange one, so I wouldn't have to do that.
After mashing and painting:
Re-installed on the engine
So then everything went back on the chassis. The centerlink tucked up into the pocket nicely. There was probably still less clearance than I should have had, but I decided it was good enough, and I pressed forward.
At some point, I decided it was probably time to think about mounting the exhaust headers. After wrestling one header up into position, I found that it was going to be impossible to install the headers, because the mounting flange interfered with the nuts on the cylinder head studs. The stock cylinder head bolts sit relatively flush to the cylinder head, whereas the aftermarket studs that I decided to use stand up a little bit taller. Why do I need studs? I don't, I just decided it would be cool to have them. When you start talking about bolts vs. studs, everyone mentions that if you use studs, you'll have to remove your brake booster if you want to remove the heads with the engine in the car. Nobody mentions that your header flange will hit them. But in my case, it did.
I figured I must not be the first person to have this problem, so I started doing some research online. A lot of people talked about installing bolts for the row of fasteners below the header flange, and using studs for all the other cylinder head fasteners. I didn't really want to backtrack and re-torque the cylinder heads, and I didn't want a mix of studs and bolts, so I kept looking around until I found some big block Chevy guys who said they'd just clearanced the flange with a grinder. That was what I really wanted to do, I was just doing research to see if there was anyone who said, "Here's why you should never do that...." I didn't find anyone who said that, so I decided to do some grinding.
(I am a little bit worried about how thin this makes the flange at the notch, and I wonder if they're going to crack/break there, but I couldn't find anyone else who mentioned problems like that, so ... I guess we'll just find out.)
The basic shape of the header flange repeats at each exhaust port, so I just traced one part of it on to a piece of cardboard, then I cut that out, put bolt holes in it, and then cut it a little bit at a time until it cleared the stud and nut:
I used that as a template to transfer the shape of the notch on to the header flange, then I cut the notches with an angle grinder. These two pics show a "before" and "after" comparison (the flange is upside down in these pics, so the notch is at top right in the second pic):
Test fit:
After cutting the flanges, I had to re-paint the headers. I ran a piece of string from the track for the garage door opener, down through the header bolt holes, up to the garage door track, and down to a cabinet handle that I tied it off to. That allowed me to balance the headers on their outlet flanges, so I could paint all the way around them in one shot.
Once that was done, it was right back to the action. Certainly, there was nothing that could stand in the way of a smooth and successful completion of the project now.
I went to install the headers on the engine, and immediately found that the driver side header was interfering with the steering box. Now, these headers are supposed to be specifically for this engine, in this car ... maybe some false information has been distributed to the aftermarket regarding the exact location of the 1965 Impala's steering box...?
It's hard to get a picture that really shows exactly where the interference is, but it seemed to be pretty slight. The cover on top of the steering box there is aluminum, and looks to be really beefy, so I thought maybe I could just file off some of the beef to create some clearance.
If you watch TV shows about car projects, or read magazine articles about car projects, or pay attention to car projects at all, you've probably heard a story about a problem with header clearance. It seems to be a commonly accepted "fix" to just put a dent in the header primary to create clearance, but I've always hated that solution. It seems like you're just "solving" one problem by creating another. Still, a lot of "pros" seem to think it's OK. But I didn't want to do that, and I figured that if I did do it, then I'd have to give up my right to complain about other people doing it. I don't know if taking a file to the steering box cover is really any better than putting a dent in the header primary, but ... in my mind it was, I guess.
I had the engine on the hoist and not resting on the engine mounts as I was doing all this. I'd hoist it up a bit, file some, and then lower the engine to check clearance. Every time I lowered the engine, though, it just dropped right through all the clearance I'd created until it was resting on the steering box again. Apparently I was off by more than I thought.
A portrait of the artist as a guy trying to figure out why his headers are all over his steering box:
OK, so now a story about engine mounts.
I decided to start by calling Hooker Headers, to see if they had any comments about what my problem might be. They asked if I was using big block mounts or small block mounts. I told them I don't know. There is a lot of interchangeability of parts, by design, in the engine mounts, and I don't really know what I have. I know there are a couple different styles of mounts, but I've never been able to get a definitive answer on what the different styles are supposed to be for. Part of the reason I got what I got was because the frame already had frame mounts on it, so I just looked around until I could find a set of engine mounts that would mate to the frame mounts. I suspect the car originally came with a small block, so those frame mounts may have been intended for use with a small block, but I don't really have any way of knowing any of that for sure, either. The VIN only identifies it as an SS V8 car, it doesn't code the specific size of V8. Anyway, I started looking around online to try to find out, what is the big block style, what is the small block style, and for the different types of mount that I'm aware of, are there any dimensional differences that would affect the position of the engine once it's mounted?
The answers to those questions ended up being, "I don't know," "I don't know," and "not that I can tell." But while I was searching around Summit looking for all this stuff, I stumbled on to something I'd never heard of before: engine mount shims. There were three or four different companies selling 3/16"-thick shims that could be bolted in between the engine mount and the engine block. At the angle that the mount is bolted up, this 3/16" shim effectively raises the engine up about 1/4" vertically. I thought that sounded better than dented headers, so I ordered a set of those, AND ... longer bolts, of course, so that the bolts would reach through the shims to bolt up the mounts.
After wrestling around with the headers and trying to create clearance, I'd knocked some paint off of the headers. The shims were unpainted as received, so it was time for more painting.
Notice that this time I hung the shims on the string in between the headers, so I could paint all sides of all things at the same time.
Of course, those of you paying close attention will be saying to yourselves, "But wait a minute, if you had knocked that pocket into the oil pan to accommodate the centerlink, and now you're shifting the pocket up a quarter of an inch, doesn't that mean that your pocket is in the wrong place now?"
Yes. Yes it does. It means exactly that. So, once again, the engine came back off the chassis, and the oil pan came back off the engine. And it was clear now that it was going to have to be cut.
To be honest, I wasn't really sure exactly how this was going to work as I started cutting, but I started by going across the front of the bottom edge. I did all the cutting using a cutoff wheel on a Dremel.
Then I cut up the seams where the flat front angles back.
I started to try to bend the bottom flap up a bit, but it didn't really want to bend where I wanted it to bend, so I went back and kind of "scored" the line where I wanted it to bend. I was still using the Dremel cutoff wheel for this, but I just didn't cut all the way through.
It seemed more ready to bend now, but I cut a couple little pie slices at the corners to provide clearance for it to swing through that area.
That allowed me to fold that lower flap under everything else.
A different angle to show the same stage:
Then I went across and trimmed off the upper flap, trying to keep it tight with the other flap.
Skipped through a few steps without photos, but basically folded the ears over at the ends and trimmed them off flush with the other flaps, then ground off all the paint to get it ready for welding.
A technician at work welded it up for me, including running a bead down the scored line at the lower edge.
Good thing I ordered it orange, so I wouldn't have to paint it.
Next, I filled it with some old, used oil, and put it on the floor on top of some clean paper towels. This was my leak check. I let it sit there for a few days, and didn't find any leakage. So, I drained out the used oil, and then very carefully and thoroughly cleaned out the pan with Brakleen, trying to make sure to clean out all the debris that went into the pan when I cut it. And then it was time to paint it.
So, I painted it, but somehow this time I didn't manage to get the top side of the "wings" painted. And you could see that pretty clearly, and it looked bad, so I decided I'd paint it again. I've had bad luck in the past with spray paint flaking off, so I've been trying to follow all the directions on the can, and the can says that once the paint is dry you're supposed to allow a week of cure time before putting on more coats, so that was a week lost. Good thing I ordered it orange, so I wouldn't have to paint it.
But wait ... it gets better. The next time I painted it, the paint was dry and I picked it up to look it over, and it somehow slipped out of my hand and fell on the floor, which knocked the fresh paint off a couple corners. Maybe I subconsciously don't even want this pan painted? So I painted it one more time. After waiting another week.
But wait ... it still gets better. The can also says that it is "EXTREMELY IMPORTANT" to bake parts painted with high temp engine paint at 200degF for one hour, to finish the curing process and get full resistance to chemicals and all that. How do you bake an oil pan? Well, you put it in your oven.
But then you can't close the door on the oven, so you make an "oven extender" out of a cardboard box coated in "Great Stuff" insulation.
Is it smart? Ohh ... probably not. But it actually worked pretty well. The box on the floor under the oven door is a digital multimeter connected to a thermocouple which is reading the temperature in the box, to make sure it's getting hot enough in there, but not too hot. There was a lot of nervous monitoring of the process. The paint is supposed to be cured at 200degF, but the insulation warns that it will ignite at 240degF, so you have to be very careful, but it is workable. I know because I did it four times. Good thing I ordered that oil pan in orange so I wouldn't have to paint it.
So, the part where it gets better is that after I painted the pan for what I thought was the last time, I baked it again, but for some reason this time the paint bubbled up all over the bottom of the pan. I'm still not sure why that happened, but it looked like junk. I tried to sand it down, but that just knocked all the bubbles off and left big "holes" in the paint all over. It looked terrible.
At that point, the pan had been painted by the manufacturer, then painted after I deformed it, then painted after I didn't get complete coverage, then painted after it was cut and welded, then painted again after I dropped it. It had at least five coats of paint on it. I was so sick of messing with the stupid thing, I thought about just giving up and putting the stock pan back on. But I also had so much time in the stupid thing at that point, I wasn't ready to just cut bait and walk away. I decided to just remove all the paint and start over.
To remove the paint, I used something like a 40-grit paint and rust removal wheel on my angle grinder. Although, I've gotta say, I really think the manufacturer of that wheel is selling his product short. It says it will remove paint and rust, but I accidentally tagged my knuckle with it once, and it turns out that it removes skin and flesh pretty effectively, as well.
Anyway, I got the pan cleaned up pretty well, then sprayed it with a high temp primer, then sprayed it one more time with Chevy orange. Baked it. All done.
But wait ... as I pulled it out of the oven, I noticed one corner that had apparently been scraped on something, which knocked the paint off of it. After a lot of cursing, I decided that I would try one more time, and whatever came out of the oven next would just have to be good enough.
So, I painted it one more time, handled it VERY CAREFULLY ... waited a week, then baked it to finish the curing process, and ... it finally came out good. Below is a side view to show how the front of the sump, which used to be a vertical wall, now slopes back at an angle for additional clearance.
Back on the engine:
In this photo you can also sort of see the engine mount shim, in between the engine block and the engine mount:
Starter motor is mounted there, too.
So, as you can see in the photo two photos up, I decided to put the headers on the engine while it was on the stand this time. I wrapped old t-shirts around anything that the headers might bump into as the engine was being lowered on to the chassis, and I dropped the whole deal down into place. Plenty of clearance in front of the oil pan now, looks like almost a full inch. And between the header primary and the steering box, maybe a quarter inch. I'll take it.
This isn't all that's been going on, there's also been tremendous amounts of cursing that I didn't mention here. And I've also been doing other work on the car. And that will be detailed here, too ... eventually.
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