Conan Writes About Automotive Repair!

So I know Katherine's pretty much taken over posting on here for the last couple of years, but that's mostly because she's so good at it. And I know we haven't really been the most frequent of posters of late, but the unfortunate thing about starting a business is that your priorities change, and writing a new blog entry every other day kind of gets pushed to the side. Sorry for that everyone, it's not you, it's us.

So I meant to post this awhile back, but my browser kept locking up on me while I was trying to write it and I just never got back to it.  Anyway, better late than never, right?

Way back last winter, while Katherine and her parents were spending most of their time refurbishing our vintage trailer, it became my task the get our lovely 1988 Jeep Grand Wagoneer into shape to pull the thing.

Here I am using my magic duster to keep the Jeep looking nice and shiny.

Now granted, I think it could have pulled the trailer just fine as it was, but there were a few things that really bothered me about it, the biggest thing being a massive oil leak. And when I say massive I mean like adding-a-quart-of-oil-to-it-every-couple-of-days massive. My oil bill was almost as bad as my gas bill (actually that's a big exaggeration, this thing drinks gasoline like a...a...thing that drinks a lot).

Anyway, this trickle of oil coming from that back of the engine was the tell tale sign of the dreaded rear main seal leak that virtually every Wagoneer owner must confront at some point. Now some mechanics will tell you to sell it at that point because all they see is an old, obsolete, high mileage, frumpy, 1980s SUV, but those mechanics obviously don't get the appeal (or know the value) of a Grand Wagoneer. But once you find a mechanic that knows anything about working on them, he or she will likely quote you a price upwards of $800 to fix the rear main seal because of how much you've got to take apart to get to it. Since I'm a bit of a cheapskate, and I'm not afraid of turning a wrench every now and then, I decided to do it myself.

Here's what I was working with:

Now, it looks pretty bad under there, without a doubt, but I had a couple of repair manuals and the wisdom of the internet to guide me, so I dug right in.

Step One: Remove Starter Motor

There's no way you're going to get the oil pan off with that starter in the way, but it's pretty easy to take off if you've got a good, and complete, set of sockets. There's one bolt on the back side of it that is different from any other bolt you'll encounter on this endeavor, but I think if I remember correctly a 15mm metric wrench will work on it. I prefer the box-end wrenches with different sized ends if you can find a good set, but standard combination wrenches work too.

The old starter was about as ugly as can be and one of the contacts broke off when I went to remove the wires, so I figured it was time to go to AutoZone and pick up a new one, which is as easy as walking in the door with the old one and walking out with a replacement. It's not too expensive, about $80 as I recall.

Yea! New rebuilt starter!

Step Two: Remove Oil Pan

Now this sounds like it should just be a matter of undoing several bolts and it'll pop right off, and basically that is what you do. However, the last two bolts that are up against the transmission are nearly impossible to get a socket on, especially with the exhaust pipe still attached. Now the smart thing to have done would have been to remove said exhaust pipe, but the bolts on the pipe had turned into little knobs of rust, and I didn't exactly like the sound of drilling busted bolts out of my exhaust manifold after they snap off. So with the exhaust still in place, assuming you have several different extensions for your socket driver you can indeed get those two bolts out; it involves some cursing, maybe some throwing of tools, but it's doable, trust me.

With all of the bolts out, you'll find that the pan itself is glued in place with sealant and is not going to drop off easily. This is when you take a nice sharp putty knife and carefully drive it between the lip of the pan and the engine block until you hear a "Pop!" and it breaks free. Great it's off, now you can just pull it out and place it aside right? No, no you can't. You see, there's a little tab on the dust cover for the transmission that it catches on, and you won't be able to see this tab, but you can feel it with you fingers. Fortunately the dust cover is easily removable by taking out the bolts that hold it on and sliding it out. Great, now you can set the oil pan aside...except that you can't.

Taking the dust cover off lets it drop down further, but you see, you've got a lot of suspension and drivetrain stuff you've got to get it clear of, plus you've got to rotate it 90 degrees counter-clockwise (looking up at it) to get it down far enough to clear the oil pick-up tube. The trick to doing this, is that the front wheels HAVE to be OFF the ground to let the suspension and everything else drop far enough to give you room. This is a must, and it doesn't seem like it makes a huge difference, but it does. Again, trust me.

All that being done...

Boom, the oil pan is off.

Step Three: Clean and Repaint the Pan

You've removed paint from metal before, it's not rocket science, get to it with some sort of degreaser and a wire wheel and knock off all the rust you can. It's also very important that you remove all of the old gasket and seal material before you attempt to even think of reinstalling the pan. On the engine block I used a scraper, but I was very careful to not mar the surface of the block; you don't want to create any potential for future leaks.

And then it's just primer and paint, but make sure you use the high-temp stuff. They recommend curing it in an oven, but don't use one you cook food in; this stuff isn't good to eat.

Now if you're just replacing your oil pan seal, you could go ahead and start putting stuff back now, but if you're going on to the rear main seal, it's time to get back underneath the car.

Step Four: Bearing Cap Removal

So this is what you're looking at with the oil pan off. Those things with the two giant, heavy-duty bolts on each are the bearing caps, and they hold your crankshaft in the engine, which is what drives power back to your transmission and so on. As you might imagine, they are really really tight, like 100 ft-lbs tight. Now, I'm not a big guy; I only weigh about 150 lbs, so it was difficult for me to put that kind of torque on them, but you can do it with a big enough breaker bar and a cheater extension if need be. But if you want the really disheartening news, you need to completely remove the rearmost bearing cap, and loosen EVERY remaining bolt slightly to relieve some of the pressure on the crankshaft. I started by taking the rear cap off and attempting to tap out the old seal but it would not budge even a fraction of an inch until I loosened the other bolts. Then it popped right out like there wasn't anything holding on to it.

 That's me on the bottom left holding the rear main seal and looking...I don't know...relieved?

Step Five: Putting It All Back

It's actually a lot easier than I expected, and basically just the reverse of removal as they say. Installing the new seal is easy, and just like they describe in the Haynes manual. I'm not sure why so many people that have replaced one of these seals say they needed to buy multiples because they ruined a couple trying to install them. Follow the book, and keep pressure on it against the crankshaft as you rotate it into place. It really is that easy. And use plenty of the red RTV sealant in all the recommended locations as described in the repair manual and you should be in good shape. Also, most importantly, don't forget to fill it back up with oil.

The finished result:

I did sort of scuff the oil pan up a bit wrestling it back into place, but I think you've got to agree that it's a lot better looking now.

Addendum:

Now, there's one little part of the story, that I've sort of glossed over here. Prior to loosening all the bearing cap bolts, I had decided that it was not possible remove the seal with the exhaust in place. And since I needed to have everything from the manifold back replaced anyway, and I wasn't equipped to do that myself, I simply cut out a section of the Y-pipe that was in my way figuring I'd just temporarily bracket it back until I could get it to an exhaust shop. In retrospect, it may still be possible replace the seal without removing part of the pipe if you first loosen all of the bearing caps, but even so, your life will be a lot simpler without that pipe in the way.

And when it's all said and done you may have busted a knuckle or two, and be covered in oil and dirt and all sorts of other nastiness, but you can rest easily; you just saved yourself almost $700! Now get out there and take it for a spin, and enjoy your oil-stain free driveway. Of course, you may still have power steering fluid stains, and transmission fluid stains, and...