The ad in the Mechanic’s Specials section of the paper read: 1989 Ford Ranger Supercab, blown head gasket. $500.00. I thought it would be a pile, but I called anyway. It sounded OK, so I went to look at it. It was surprisingly clean, and even ran on all six cylinders although the oil looked like a vanilla milkshake, so I took a chance and bought it on the spot. The seller told me that if it turned out to have a cracked head, he had another engine at work with fresh heads and a rod through the block, and I could have anything I wanted off of the motor. I towed it home and did a compression test and cooling system pressure test. Compression was great (150-165 on all six) and the cooling system held 13 psi for about 15 minutes while I did the compression test, so I changed the oil, flushed it and changed it again, to see what would happen if I drove it for a few days. I was thinking maybe the intake manifold gasket was leaking, and he told me later that he had put some stop-leak in it. Well, it gradually started to have that milkshake look to it, so I decided to tear it down and see what there was to see. It was about that time that I discovered FTE, so I went on and asked for some advice, and got some truly good suggestions. Here is the basic teardown process that I used.
First, get a good manual, you will need to refer to it countless times for all sorts of little things. I prefer the Chilton’s over the Haynes, I have both but I find that Haynes leaves out or skips over a lot of important details, or puts info you need in strange places that makes it hard to find. Study the pictures of component layout to familiarize yourself with what everything is that you are looking at. As you begin to disconnect things, label all your connectors and hoses so that you can put it all back together easier.
I did not have to disconnect any A/C components (See figs. 1 and 2), I was able to move the compressor out of the way on the driver’s side inner fender panel. Likewise the power steering pump, bungee cords are convenient to hold these components out of the way. The PS pump bracket needs to come off as it bolts to the driver’s side head. Also, remove the alternator. While I was at it, I pulled the fan shroud, fan, and the fan clutch. My fan was cracked and looked ready to grenade. You will need a tool to disconnect your fuel lines where they hook up to the fuel rail on the driver’s side just above the valve cover. There are two types of this tool that I have seen, both readily available from your auto parts store. I paid about five bucks for the scissor-type, which is probably the cheaper of the two but a little harder to use. It’s still pretty simple though, I had both lines off in about 30 seconds.
Next you’ll need to remove the upper and lower intake manifold. Your distributor will have to come out in order to gain access to the rear intake manifold bolts, and to remove the lower manifold so if your timing is correct and you want to get it back in place pretty close, pull off the cap and wires to get them out of the way, noting the position of the number 1 terminal on the cap. Most of these I have seen have a #1 right on the cap, but check it to be safe. Now look to see where that terminal lines up on the distributor housing and turn your engine to TDC on the timing pointer and look at the rotor to see that it is pointing to the right spot that you have noted on the distributor housing. It will either be ‘Spot on’ as the British say, or 180 degrees off. If the latter, turn your crank over one complete turn till the timing pointer lines up with TDC again and you should be right there. Now, you need a way to mark the housing and the base of the distributor where it goes into the block and where the hold-down clamp is located. If you’ve ever bought parts at a wrecking yard, you’ve probably seen them mark the parts with a paint pen, a little bottle of fast drying paint with a ball-point tip, usually yellow. A lot of auto parts stores sell that very same thing, in various colors. I have some, and it was useful for this and another operation I’ll describe later. Put a mark on the edge of the distributor housing where the rotor is pointing to #1, another mark on the base of the housing at the block junction, and a corresponding mark on the block. This will be a little tough to do because it’s hard to see back there. Make sure you are marking on clean surfaces. Pull the clamp bolt and gently pull up on the distributor, watching how far the rotor turns, as it will do a little due to the bevel-cut gears. Set your dist. aside with the rotor in this position, or make another mark if you like. Lining these marks up during reassembly will make it go back together with the timing very close so that it should fire right up. Drain the coolant, if you haven’t already done so. When the radiator is empty, pull the lower hose off to get a little more coolant out of the engine, otherwise you’ll end up with it going into the cylinders and the crankcase.
Now you can really get into the disassembly process. Pull the lower intake manifold, noting where the different size bolts go. I used separate containers to put all my fasteners in, marking what they were for so it was easy to find the right ones during reassembly. Pull the valve covers, and then the rocker arms and pushrods. If you are going to reuse the rockers and pushrods, then keep them in order so that they can be placed back where they came from. Now for the heads. You will need a T55 Torx socket for the head bolts, you can get them in 3/8 or 1/2 inch drive, ( see fig. 3) would be better as you’re going to put some torque to them when you reassemble. Toss the bolts, you’ll have to replace them as they are designed for one-time use only and are now stretched. Gently pry the heads from a corner to break the seal, and have rags ready to mop up any coolant that might remain and will run into the cylinders. Peel off the head gaskets and toss it.
Now it’s time for a good inspection of the heads, unless you have already decided to replace them. Look at figs. 4 and 5 and you can see the cracks in the stock heads, cylinders 1 and 6. Figs. 6 and 7 show the differences between the Ford heads and the World Products heads.
Fig. 4 Fig. 5
Fig. 6 Fig. 7
Now it’s time for some clean-up. Fig. 8 shows the single-edge razor blade scraper that I like for stubborn particles of old gasket, but you have to be careful with it on aluminum as it will gouge easily. I like to have good supply of clean rags on hand, and some carburetor spray cleaner, such as Berryman’s B12. I’ve also become partial to Castrol’s Superclean. I like to get everything as clean as possible. Figs. 9 and 10 show the block after cleaning, see fig, 1 for a comparison. In Fig. 11 you can see the thread chaser I made out of an old head bolt. This particular bolt came from a 2.3, but the thread is the same so I used it on the 2.9 as well. I just took an old bolt and ground channels in it with a 4” angle grinder. You couldn’t of course use it to cut new threads, but it works fine for cleaning existing threads.
Fig. 8 Fig. 9
Fig. 10 Fig. 11
Reassembly is basically the reverse of disassembly, with care taken in certain areas. Place your head gasket on the block, being certain it’s in the correct position. Gaskets should be marked FRONT and TOP and are not interchangeable from side to side, and then carefully set the head squarely in place on top of it, so that you don’t set one edge down on it first and possibly gouge the gasket which could cause a failure later. Apply a little ATF or other light oil to the threads of the new head bolts, and some assembly lube to the underside of the bolt heads where they will contact the cylinder head, and drop them in place snugging them but not tightening them yet. When they are all in place and snug, set your torque wrench for 22 ft.-lbs. And tighten the bolts in the order shown in the manual. Then bump the torque setting up to 55 ft.-lbs and do it again. When you have done the whole sequence, do it again to ensure that they are all up to spec. Now get the paint pen I mentioned earlier and mark all the bolts on top at the same orientation so that the mark is parallel to or exactly 90 degrees from some point of reference. Now you need to turn the bolts 90 degrees, and the reference mark you have made on each bolt will help you to see that you are doing so.
Rocker shafts and pushrods are next, with a spot of assembly lube on both ends of the pushrods, and the tips of the rockers where they contact the valve stems. Install the rocker shafts bolts and tighten to 45 ft. lbs. in stages, starting from the middle and then going to the ends Fig. 12 shows the heads and valve train in place. Note the yellow alignment marks I made on the
head bolts for when you torque them. Next, reinstall the lower intake manifold. The Fel-Pro gasket set that I used has a perforated one-piece gasket with no end pieces, but comes with a small tube of silicone to make your own. I don’t like to use much silicone in an engine but I didn’t have much choice at this point. Run a bead on the block at each end, with a little extra at the corners. Try to get the bead as even and uniform in size as possible, and about 1/4 inch thick. Set the manifold in place and bolt it down, following the torque sequence and specs in the manual.
Now set your engine to TDC on the compression stroke. This is easy to do since you still have the valve covers off. Turn your engine by hand with a 19mm socket on the crank pulley bolt, while watching the rockers on the #1 and #5 cylinders. You want to see movement on the #5 but not the #1 rockers. Since these two cylinders are directly opposite other in the firing order, the #5 will be at TDC in its exhaust stroke, while #1 is at TDC in its compression stroke. The #5 exhaust valve will have just closed, and the intake is just starting to open. If you are seeing movement on the #1 rockers, then you are 180 degrees off and need to turn the crank one full turn. If you have not disturbed the position of the crank since you took the distributor out, then you can disregard all this info on finding TDC, but I found it necessary to turn the engine over as I cleaned the debris out of the cylinders during the cleanup process. Plus, I wanted to inspect the cylinder walls. Reinstall the distributor, aligning it with the marks you made during the disassembly process. You should be able to set the rotor to the secondary mark you made on the rim of the distributor (you did, didn’t you?) And then slide the distributor down into it’s hole. The rotor should turn a little to the left and line up with the first mark on the rim, the one that lines up with the #1 terminal on the cap. Now check your mark on the distributor base, make whatever adjustments are necessary to line it up, make sure that the rotor is still in the proper position for #1, and if it all looks good, install the hold-down clamp and snug it in place. If it’s not lined up, you will have to do it again as you are a tooth off. Your timing should now be very close to where it was before you started the teardown. Install the upper intake manifold and torque to specification.
You should set the valves if yours are adjustable, and you have changed anything in the valve train. Just changing the cylinder heads is enough to make me want to check the lash, but I also installed new lifters, and the donor engine I got the heads off of had pushrods with hardened tips. (See fig.13) Earlier 2.9s had adjustable rockers, but if you have the later non-adjustable rockers, you just have to go with them as they are. You want to start with #1 since you have that cylinder at TDC on the compression stroke from the distributor installation, and both valves are closed. Loosen the adjuster, while feeling for play in the rocker. It’s very touchy, the plunger in the lifter will depress, especially if they are new lifters, you have to feel for the slight bit of resistance that comes in when the plunger begins to depress. When you have taken up the play in the rocker but not yet depressed the plunger in the lifter, now you turn the adjusting screw 1 turns in (clockwise) to preload the lifter. You can do this with the intake and exhaust both on #1 at this time. Now move on to adjusting #4, the next cylinder in the firing order. Turn the engine a little so that you are now at TDC on the compression stroke for #3, the opposite cylinder for #4, look at the opening and closing of the valves on #3, and of course you have no timing mark available now. When you are done with that one, just move on to the next one in the firing order, #2, opposite is #6, then #5 opposite #1, #3 opposite #4, and # 6 opposite #2.
On to the installation of the valve covers. Inspect them for distortion of the flange around the bolt holes caused by over tightening to try to stop the oil seepage that seems to be so prevalent with these engines. If you find any, hold the edge of the cover upside-down against a hard surface so that you can lightly hammer them back into shape. I like a rubber gasket rather than cork, use just a spot of silicone sealer at the junction of the head and intake manifold, and glue the gasket to the valve cover with a coat of Gaska-cinch. If you expect to remove the covers soon, then don’t put any between the gasket and the head, otherwise a coat there will serve as a little extra insurance against leakage. Look at the reinforcement washers that go on the bolts, and you will see that they are two slightly different shapes. You will need to refer to your manual here for a diagram that shows the positions of these washers. The torque specs for the valve covers are only 3-5 ft.-lbs, or 36-60 inch-lbs. Most torque wrenches that I’ve encountered don’t really read very accurately at that low a setting, so I just tightened them by feel. You don’t want to really crank on them, (remember, you just straightened them out!) but you want them good and snug. It’s sort of an acquired feel, I guess. So, now hook all your wires and hoses back up, refill with coolant, change the oil, (I would, anyway) and you’re ready to go! Figs. 14 and 15 show the finished product. Hope it all works out for you.
Fig. 14 Fig. 15