From herbh@iastate.edu Wed Jul 17 12:27:05 1996 Date: Thu, 11 Jul 1996 08:12:29 -0500 From: Herb Harmison To: gsker@lenti Subject: H20 Head Gasket-How To 1/2 July 11, 1996 Herb Harmison, 2692 Meadow Glen Road, Ames, IA 50014 515-292-7059, herbh@iastate.edu With thanks to Jim Davis and Fred Dyen for their input and suggestions and to Dan Houg who offered guidance and support while I tackled this job. Replacing Cylinder Head Gaskets on a Wasserboxer, in this case a '91GL. Bentley is very terse in their directions about the job. The following are my suggestions after doing the job once. Preparation: You will need a good set of tools. All the fasteners are metric. However, a 1/2" box or open end wrench is useful for holding bolts. The most used socket is 13mm. You should have both a 3/8" drive and a 1/2" drive along with several extension bars. You will need a 1/2" to 3/8" socket adaptor. You will want a set of metric hex wrenches as well as a metric hex set. A box of sandwich bags to keep parts in and scratch paper to note what the parts are from. An old egg carton or muffin tin can be used for small parts and fasteners. In order to work under the van you will need some rather tall jack stands or, as I have, some VERY stout(2"x8" material) boxes. My boxes are about 9" high so I can jack one side of the van up at a time and slide the boxes under the wheel. I also have jack stands under the frame, just in case. You will need a couple of sticks, dowels, pipe or bars about 4' long to hang components on. Also some wire or rope. You should have a full can of Liquid Wrench or similar product. Mouse milk is the best penetrant available. Obtain from any aircraft supply house for really stubborn components. A pan to catch oil and anti-freeze and some floor dry to keep your work area clean. Rags and paper towels are very handy. A good drop light is necessary. I find the most economical light bulb is a standard rough service bulb onto which I put a coating of clear silicon over the exposed half of the bulb. Coating prevents breakage when splashed with liquids. First job is to drain the engine oil. Do his while the van is on the floor and, hopefully, the engine is hot. BENTLEY SAYS: DISCONNECT BATTER GROUND STRAP. Herb says: If you have trouble with this step, stop and hire the job done. BENTLEY SAYS: REMOVE REAR MATTRESS(WHERE APPLICABLE), CARPET, ENGINE COVER. Herb says: ditto above. BENTLEY SAYS: REMOVE AIR CLEANER ASSEMBLY. Herb says: There are 3 clamps that hold the assembly to the engine. Be sure you disconnect all. The pipe fittings will come off with a gentle pull and the entire assembly will lift out. No bolts or screws. BENTLEY SAYS: REMOVE A/C COMPRESSOR FROM BRACKET, LEAVE HOSES ATTACHED. Herb says: Loosen the fan tension by backing out the adjusting bold several turns. Once the belt tension is gone, you can remove the adjusting bolt "nut". The nut is a small casting on the stamped bracket. Then loosen the compressor pivot bolts that go through the right side of the compressor and the cast mounting bracket. The compressor will come off with just a bit of effort. Wire the compressor to one of the sticks mentioned above placed front-to-back across the engine compartment opening. It should be up as high as possible without stretching the hoses. BENTLEY SAYS: REMOVE LEFT/RIGHT FUEL RAILS, INJECTOR GROUND WIRES AND INTAKE MANIFOLDS. Herb says: Do not remove the injectors from the intake pipes. The injectors are the two small pieces that are inside the fuel rail. They have wires connected to them and are held in place by a 10mm bolt. The injectors will be very happy to ride with the intake pipes. You do need to take the intake pipes off the heads. This is done with a socket wrench on the two bolts on the casting. When you have finished you should be able to pick the pipes up off the heads a couple of inches. You may note the connections at the distribution box in the center of the engine come loose. No problem. Just remember to put them back on when you're finished. On the left side wire/tie the intake pipes up as high as comfortable. I ran a wire through the mounting holes in the casting. On the left side is a ground wire with a brown wire and a pipe bracket. Remove them. The is no ground wire on the right side. BENTLEY SAYS: REMOVE THE LEFT/RIGHT SPLASH SHIELDS. Herb says: These are the two shields slightly outboard of the engine. There are 7 sheet metal screws holding them on. The bolts come out easily. BENTLEY SAYS: REMOVE THE PUSH ROD TUBE SHIELDS. Herb says: You may already have one or both off. Only by taking the shields off can you tell where the leak is and what the condition of the gasket is on the bottom of the engine. 13mm socket works well although you may need a universal joint to get at the rear bolt on the left side. BENTLEY SAYS: DISCONNECT OXYGEN SENSOR Herb says: The O2 sensor is mounted just before the catalytic converter which is just before the muffler. Spray some Liquid Wrench on it. It has a silver heat shield over it which snaps off after a little freeing up. I used a good sized 7/8" open end wrench (there is probably a metric size but I had a much larger 7/8" wrench) and applied some force and it came right off. BENTLEY SAYS: REMOVE COOLANT DRAIN PLUGS AT BOTH CYLINDER HEADS, DRAIN COOLANT FROM ENGINE. Herb says: The plugs are centered between the push rod tubes on the bottom of the engine. You will see two plugs about 1" in diameter, one with a bolt in it. Each side is the same. Here you will need a 6mm hex wrench. On one side a hex socket will work fine. On the other side you may need to use a hex wrench. I didn't want to push on the tube too much. If you use the "L" wrench you will need to turn it with a Vise-Grip or a Cresent wrench as the bolt is pretty tight. Put a liquid catcher under the engine and remove the cap(You will need to take the hose off the cap before turning.) from the expansion tank in the engine compartment to let air in and get a nice smooth flow of coolant into your catch pan. BENTLEY SAYS: DRAIN ENGINE OIL AND REMOVE THE OIL FILTER. Herb says: You should have done it already. Bentley notes that you should not replace the plug until afer repairs are completed. This is probably to keep oil flowing out, but that makes a mess. I put it back in and figured I would remember to fill it with oil when I replaced the filter. BENTLEY SAYS: REMOVE SPARE TIRE COVER UNDER FRONT OF VEHICLE, DISCONNECT COOLANT HOSES. RECONNECT RADIATOR COOLANT HOSES. CLOSE SPARE TIRE COVER. REMOVE COOLANT PUMP. Herb says: I didn't do any of the above. It may cut down a little on the dripping but I didn't have any problem with dripping. BENTLEY SAYS: REMOVE EXHAUST SYSTEM, INCLUDING CROSS-OVER PIPES, MUFFLER WITH CONVERTER AND EXHAUST HEAT SHIELD. Herb says: This is the fun part! First, use Liquid Wrench and then remove the nuts and bolts holding the exhaust pipes to the heads. You will already have taken two off each side to remove the push-rod tube shields. They are 13mm and come off with little problem. You will note that there are studs on two outlets and bolts on two outlets. The best way to remove the muffler and pipes is to remove or cut the three bolts in front of the catalytic converter. On my van these were pretty badly rusted and I found I could saw through them with little difficulty. The rear muffler assembly is simple to remove. Do not remove the two bolts holding the muffler strap. These are easy to see and get to but useless to loosen. Instead, loosen the 4 bolts in front of the muffler. There is a mounting bracket that lets the whole muffler assembly come out when these bolts are removed. This is where I used the 1/2" wrench to hold the 13mm bolt heads. The assembly is a bit heavy so be careful as it comes out. That leaves the exhaust pipes to get out. Remove the 3-13mm bolts holding the mounting plate to the bottom of the engine. When the last one comes out the exhaust pipes will be loose but won't drop as they are held in place by the studs in the head. A little pushing and pulling and the whole assembly comes out quite nicely. BENTLEY SAYS: REMOVE CRANKSHAFT PULLEY. Herb says: Don't do it. This is an error. There is no reason to do this. BENTLEY SAYS: REMOVE POWER STEERING PUMP. Herb says: The pump is located on the right rear an is bolted to the right head. It can be removed by loosing the belt tension bolt(13mm) and then unbolting the pump from the head(17mm). You don't need to use a second wrench on this nut at the bolt has a square shoulder. When you have th pump loose, wire it up to the second stick placed parallel to the first stick. Also wire up the right intake pipes so they are completely clear of the head when you pull it out. BENTLEY SAYS: REMOVE COOLANT CROSS-OVER PIPES AT FRONT/REAR OF CYLINDER HEAD. Herb says: These are hoses attached to the heads with a 2 1/2 foot metal pipe between. A set of slip joint pliers is handy for compressing the spring clamps. The hoses come off with a bit of tugging. (Repeat of above if not already done. There is a 10mm bolt on the left side head toward the rear of the head that holds the ground strap, a brown wire and a flat strap. You will need to remove this bolt and put the bolt back into the head for safe keeping.) BENTLEY SAYS: REMOVE VALVE COVERS, ROCKER ARMS, PUSH RODS, OIL FILLER PIPE. Herb says: Use a screw driver to snap off the valve cover retaining spring(the long wire). Watch your fingers before it snaps...when it snaps it's too late. Take the spring off by pulling one end gently to the front or back of the van. Rocker arms come off with the two nuts on the square surface. Handle the assemblies gently and put them aside on a clean towel or cardboard. Once the rocker arms are removed, the push rods can be lifted out and placed on the towel in the correct order and with the correct orientation i.e. the "in" ends pointing in. The oil filler pipe does NOT have to be removed. Actually, there is almost no way to remove it. One of the two nuts holding the pipe is in such a location that no tool I can find or imagine will turn the nut. BENTLEY SAYS: REMOVE CYLINDER HEAD CAP NUTS, PUSH ROD TUBES AND CYLINDER HEAD...STUCK CYLINDER SLEEVES MAY BE REMOVED BY LIGHTLY TAPPING WITH SMALL RUBBER MALLET. CLEAN OLD GASKET MATERIAL FROM CYLINDER HEADS, ENGINE BLOCK, VALVE COVERS(do it) INSPECT SEALING SURFACE OF CYLINDER HEAD, REPLACE IF PITTING OR CAVITATION PRESENT.(Cavitation is an incorrect term as there is no chance of cavitation in an IC engine because the coolant is moving much too slowly. What they should have said is "or crevice corrosion is present.") (see below about replacement) MARK MATCHING NUMBERS ON PISONS/CYLINDERS(do it) PULL OUT CYLINDER SLEEVES WITH TOOL 3092 UNTIL PISTON CIRCLIP IS VISIBLE.(forget it) REMOVE PISTON CIRCLIPS, WRIST PINS WITH TOOS 3091, 3159(forget it) Herb says: There are 8 cylinder head nuts (17mm). 4 inside the valve cover and 4 above the valve cover. The ones above the valve cover will probably be dirty and need some compressed air to get the socket on securely. Here is where you will need the 3/8 to 1/2 adapter. My 1/2" drive 17mm socket would not fit in the recesses in the head on the front and rear nuts. However, my 3/8" socket worked fine. The nuts are torqued pretty well and they were very reluctant to turn easily. They seem to fight back and scream as you turn them but after a half turn or so, they are finger loose! If you have all the stuff off the head, it should pull out easily complete with cylinders. Bentley is full of it when he says "stuck cylinder sleeves may be removed by lightly tapping with small rubber mallet". After doing the job, I think the best technique is to not worry about the cylinders coming off with the heads. My left head fell off the cylinders after spraying some Liquid Wrench around. The right head held on to the cylinders as if they were welded. I sprayed, heated, beat, wiggled, wedged and wished to no avail. I finally took the cylinders out with the head, put the head in a vise and pounded with a rubber hammer, gently drove wedges between the head and the cylinder bosses and generally had a challenge to get the cylinders off. They didn't pop out like the left side but reluctantly started to give and finally came out. I figured I was in deep trouble with the cylinders off the pistons. Not really. Actually, it made for a better repair job. For one thing I could replace the "black 0-ring" at the bottom of the cylinder. For another, I could replace the piston rings which, at 100k miles, were probably due. I could also clean out the upper o-ring groove properly. Now at this point, Bentley sort of leaves us to ourselves. Clearly there are several jobs that need to be done. The heads, if not replaced, need to be repaired. There is a great explanation of how to do this from Dan Houg in the '96 archives. Search the archives with the words H2O Head pitting repair. If you use "H20 Head" the article pops to the top. The sealing surfaces on the block need to be cleaned. Do this with a combination of small wire brush and a flat file. Use the file gently so as to take off crud but not metal. The piston rings need to be removed and the carbon in the grooves removed. Buy a ring pliers at your FLAPS. I bought one from Snap-On for $5 and change and then saw the EXACT same tool from Lisle for $4.75 at my FLAPS. The tool will help save the rings when you install them. You will find the work on the piston and the block to be a bit stressful on your neck so try to arrange a headrest of some sort. Be sure you have good light so you can see what you are doing. Rotate the engine to get the piston you are working on to top-dead-center. If the belt to the alternator is still on(it should be), you can turn the engine by grabbing the belt. Be sure the hand brake is on and the transmission is out of gear. Turn gently so that if a piston hangs up in the block, you will not damage it. When you have the piston at TDC, put a breaker bar on the alternator pulley nut and clamp the bar so it won't turn or fall on you. That will hold the piston in the proper position. There are three/four/five rings on each piston depending on how you count them. Actually, there are three grooves in each piston. There is a compression ring at the top. Then a sealing ring. Then the oil control ring(s). VW used a cast iron ring for the oil with a spring under it. Remove rings from the top down. When you get to the oil ring, take off the ring and then gently rotate the spring until you find the break in the spring. The break is not obvious. The spring goes all the way around the piston and then a wire of 3-4" goes into the other end of the spring to make it as continuous as possible. Gently try to spread the spring and you will find the break. Then just pull it apart and you're done. The replacement rings I bought have 3 rings for oil sealing. There are two flat rings and a corrugated retainer. There will be significant carbon build-up in the piston grooves. You need to get as much out as possible so the rings will compress into the grooves. If there is carbon, you will not be able to compress the rings when you put the cylinder back on and the cylinder will stick or break a ring. I hammered out some small ring scrapers from fairly large carpenter nails that work pretty well. I will be happy to send them to anyone doing the job for the cost of postage. If you want to make them yourself, I will suggest a design. After I scrapped the grooves, I cleaned them with some heavy string. You will want to take off some, if not all, of the carbon on the top of the pistons. I tried to get it off with a wire brush but was not very successful. Since there was not a great deal, I left it on figuring it would blow off during high-speed driving. You will want to check the valve seats to see how much cracking has occurred. A small crack in the heads between valve seats does not make the heads useless. Be sure you reinstall the coolant drain plugs on the bottom of both heads. I had a problem putting the cylinders on the pistons until I figured out the process. First, you need the right tool. A very workable tool is Snap-On RC-980 which has a price of $42.55. It is a ratcheting pliers with a set of 6 steel bands. The band for the 3 11/16" piston in the 2.1L engine is just a bit short for easy use. If you are a decent welder, you might add 1/4" to the steel band. On the other hand, I got by with the standard size. Contact me if you would like to borrow my compressor set. There is one trick. You must modify the band a bit. The pliers fit in two little knobs at the end of the bands. The knobs are in a U formed by the band end. I found that bending the outer part of the U down just a bit I could get the band off the cylinder after putting the cylinder on. Don't change the profile of the metal that touches the piston, just the very end edge. The clearance seems trivial but it is not. Once the piston grooves are cleaned, you can install the rings. Do this carefully and gently. The top two rings may have top and bottom sides so check the instructions that came with the rings. The location of the ring gaps should be opposite. I put mine in with the gaps at the top and bottom so the cylinder would compress them as it went on. I didn't want the ends of the rings popping out after the compressor left the ring and the ring encountered the gap at the bottom of the cylinder. I was able to reinstall an old oil ring after I screwed up by bending a new oil ring before I learned you have to have the grooves clean. I did a thorough job cleaning the old ring. As long as the grooves and rings are clean, the rings will fit nicely. I made a minor modification to the cylinder which may have helped getting them back on. At the bottom of the cylinder you will see that there are two heights. The lower edge has a small champfer on the inside that should assist in putting the cylinders back on. Pretty clearly, the manufacturing process that could put a champfer on the upper edge would be very expensive, so they didn't. I decided to champfer all the bottom edges so the cylinder would be able to help push the rings into their slots. A 1/2 round fairly fine file works nicely followed by some fine emery cloth. I filed the angle pretty steeply, at least 60 degrees. Be very cautious not to let the file touch the working walls of the cylinder. Cylinder preparation requires that you clean out the o-ring grooves. One is on the bottom and the other at the top. Both rings will look black and come out in small chunks. Be sure to run a tool, I made my own, in the grooves. The grooves should be very clean. Before you put the cylinder back on, wipe everything down well with a clean rag, the inside and outside of the cylinder and the piston. Be sure you put one of the "thin black" o-rings on the bottom of the cylinder and seat it firmly in the groove. Do not put the top, green 0-ring on yet. From herbh@iastate.edu Wed Jul 17 12:27:13 1996 Date: Thu, 11 Jul 1996 08:12:48 -0500 From: Herb Harmison To: gsker@lenti Subject: H20 Head Gasket-How To 2/2 Now comes the fun part, getting the cylinder on the piston. In order to make the job easy, you will want to put a nice coating of engine oil over the piston and in the cylinder. If you have complete lubrication, the cylinder will slide on easily. Take the steel band of the ring compressor and place it so the knobs(opening of the ring) are at the top(up) between the head bolts. While the head bolts look to be about the same distance apart, there are a couple of hair's difference and the top is the only place the compressor will work. Note that the knobs on the compressor are not centered on the band. Put the band on so the knobs are closer to the outside of the engine. You may be confused as the band has a mark saying "up". If you think about the normal engine and the fact that you are usually putting a piston in a cylinder, this makes sense. We are putting a CYLINDER ON a piston. The offset on the bank lets the back taper up a bit and holds the "working" edge down on the rings. The band will fit on easily. Do a finger check to see if the rings are hanging up. Just compress the band with your fingers and see if they seem to be compliant. You will not be able to push them down all the way. Next put on the ratchet pliers. You may have to do a little juggling to get the pliers on the knobs but they will go. Good light helps. Squeeze the pliers tight and check to see that the rings are all down. If they are not, you have carbon or something else holding them up. The plier handles will want to drop down in your way. Get a string or wire and tie them up to the rods that are holding the A/C compressor, power steering pump or the intake manifolds. Now, checking to see that the large boss near the top of the cylinder is next to the adjacent cylinder, gently push the cylinder on. You can turn a bit as the cylinder goes on but do not hammer or use any force. If the cylinder seems reluctant, find out why. I had this problem and took off rings until I found one that had carbon under it. A good assembly will slip on without any extraordinary effort. You will have done the job when you can just get a head nut to start on one of the lower head bolts. I put a nut on to keep the cylinder in position while I was wrestling the compressor ring off. Now comes the second half of the job. Getting the compressor ring off the cylinder. There is actually zero or less clearance. Anyway, take the pliers off. That should be easy. Then get about a foot of brazing rod and bend it so it has a tight(180 degree) hook at one end and a 90 degree bend about 8" from the hook. The tight hook will catch the compressor ring. If you make the hook good and tight, you will not run the risk of damaging the black o-ring. The 90 degree bend will be what you pull on. Start at the top and get a bit of the ring over the cylinder. Then work around until you have the ring over the cylinder. You will have to tug here and there and maybe use a screwdriver to help get the ring over. I had to push a bit on one of the head bolts to get the ring free. It will come. Be careful in tugging not to pull the cylinder out. Once you have the ring off you can push the cylinder into it's hole. Not much that feels better than having that damn cylinder go into it's hole nice and easy. As Bentley would say, repeat for the other 3 cylinders. That's about all there is to it. Just be sure you put each piston to TDC when you're working on it. Watch to make sure you don't accidently push a cylinder out as you are rotating the engine. After all 4 cylinder are nicely fitted and pushed home, you are ready to reassemble. I took the push rod tubes, some solvent and a nice rough kitchen pad(plastic) and cleaned them up. They really shined and made me feel that I was doing quality work. I also stretched them out to just under 7 4/3". Bentley says 7.6" so I figured a bit more would not hurt anything and perhaps make them seat a bit tighter. I also cleaned off the head nuts. I filed the bottoms of the nuts ever so gently so they would seal well. Put the green o-rings on the top of the two cylinders you are working on. Push them down so they seat nicely. Also put the aluminum cylinder sealing ring into the head. Use a bit of heavy grease to hold it in place while you install the head. As mentioned above, I think, you need to have the surfaces of the block and head nice and smooth and ready for sealing. At this point you need to think through the next series of events as there are several sealants you need to manage. A sequence that worked well for me was to put the sealing rings on the push rod tubes. I used a little of the RTV Copper stuff which is supposed to be good to 700F. I put a thin coat on both sides of the sealing surface, slipped the white seals on and put the tubes aside. Leave the surfaces that will touch the head and block without sealant. I then took the black stuff from VW that is gasket sealant and put a thin coating on the sealing surface of the block. I then put a pretty continuous bead in both grooves of the head gasket. Gently put the head gasket on and made darn sure the gasket was nicely set on the block. You will get your fingers black but it comes off with some solvent. I put red stuff on both ends of the push rod tubes and on the push rod tube seats on the block and the head. Not a whole lot, just a coating. Then I put a continuous strip of black stuff on the edge of the head. Now, with the head on a clean paper towel and the push rod tubes on another towel, I put the head on the bolts and then juggled the tubes into place. It's not too tough but just keep the tubes from falling. As the tubes get close to being seated, rotate them a bit to be sure you get them seated well and the sealant is mushed. Push the head down and you should be ready to put the nuts on. Four of the nuts are weathered and go on the top side. The shinny ones go on the lower set of bolts. I ran the nuts up until I had compressed the tubes and gasket a bit. I then backed out half the nuts and put the yellow nut sealant on the bottom. I then did the other half. Doing this left the nuts with minimum to turn with sealant so the chance of pushing the sealant out was small. You will now get to torque the head. As Bentley says, don't use the click type torque wrench. Three reasons I can think of. First, the clickers cost a good deal more. Second, the accuracy of a pointer wrench is easy to verify. Third, the sealant will ooze from around nut and the torque will hold while you turn the wrench. Keep turning until you hold the proper torque. The first tightening will be to 7 ft-lb, then to 30 ft-lb and finally to 37 ft-lb. Be certain to follow the approved sequence of tightening shown below. 7 1 3 5 6 4 2 8 If all goes well, you should see some black goop ooze out from under the gasket. That is good. Do the other side in exactly the same way. BTW, the heads are identical on all but the early 1.9 liter engines. Check to see if both heads have been drilled for the power steering pump. If not, the undrilled head can be modified. Now another interesting job...installing the pushrods and setting the valves. I think it is good to set the valves even though you didn't change the heads. The valves are hydraulic and need only one adjustment. first step is to put the push rods into the tubes. The second step is to put the rocker arm assembly onto the posts. Don't tighten the nuts more than finger tight. The lifters in the block are cupped in the center. It is pretty easy to get the push rods on the outer surface of the lifter and ruin things. As you snug up the rocker arms, rotate the push rods so they slip in just a bit more. If the push rod is not seated, it will be apparent when you set the valves. Setting the valves is relatively easy. First, take off the distributor cap(two spring clips). Then turn the engine over until you have the rotor pointing to the #1 positon. This is about 3:30 on the distributor but better identified as a groove on the distributor housing. In this position both valves on #1 will be closed. Loosen the lock nut on the rocker arms and turn the adjusting screw up or down until you just touch the push rod. Again, be sure you have the push rod in the lifter depression, not on the shoulder. Then turn the adjusting screw down 2 more turns and lock it tightly with the lock nut. Now, turn the engine 180 degrees and the next cylinder is ready for setting. Since there are no more marks on the distributor, you will need to make marks on the flywheel. When you are at TDC you will see a small notch in the flywheel. The next cylinder is #4. Check the top of the alternator to determine the direction to turn the engine. Mine has a little arrow. Actually, it is clockwise as you are facing forward. The firing order is 1432 with the cylinders numbered: Front 3 1 4 2 After you have done all the valves, make a visual check to ensure you have all the adjusting screws about the same distance out from the locking nuts. If there is any noticeable difference loosen the adjusting screw and see if the rod is properly seated on the lifter. Replace the distributor cap. Once the valves are all set, put the valve cover on. I put red sealant on all the sealing surfaces trying to keep oil from leaking. Put the wire spring back on the holes in the head and pry the spring up to lock the valve cover on. Watch your fingers...that spring is mean. BENTLEY SAYS: REPLACE COOLANT CROSS-OVER PIPES AND FRONT/REAR OF CYLINDER HEAD. Herb says: Do it. This is a pretty straight-forward job. Put the hoses on the heads with a little sealant and snap the hose clamps on. I should have purchased a Mobea type pliers to remove the hose clamps. I see they cost $13 and $22, depending on size, from Snap-On. A good pliers would have saved some considerable amount of lost effort. BENTLEY SAYS: REPLACE THE POWER STEERING PUMP. Herb says: Do it. Tighten the belt to running tension. BENTLEY SAYS: REPLACE THE EXHAUST SYSTEM, ETC. Herb says: This will be fun. You will probably want to replace all the bolts and nuts with good stainless ones. The bolts and nuts cost about $.40 each at our local machine supply place. I put out about $12 for nuts, bolts and washers. You also should put the bolts in so the next repair job will be a bit easier. Use ample anti-sieze compound. Think ahead. The trick here is two fold. First you need to get the gaskets in the correct location. Then you need to attach the push rod shields using the exhaust pipe bolts and studs. I think the best way to do the job is to have the exhaust system in two parts with the muffler and catalytic converter making up one part and the pipes the other. Put the header pipes on the heads with the gasket(metal side to the head). Snug up the top bolts/nuts at each of the 4 ports while you have the lower bolts(2) in their holes. Understand you will have to take the lower bolts out to put the shield on. Bolt the support plate to the bottom of the engine with 3 bolts. Keep the bolts loose. Install the muffler and converter using the 4 bolts just in front of the muffler. Tighten up the bolts. With all the exhaust system in place, replace the push rod tube shields. These bolt to the lower bolts and studs of the exhaust header flanges and head. Once the bolts are in the header flanges, you can tighten all the bolts and nuts of the exhaust system. Replace the O2 sensor. Put a some reverse twist in the wire before threading the sensor in. That way the wire will not be twisted. Replace the splash shields on both sides. You are now pretty well done on the bottom side. Good work! Next you need to put the intake manifolds back. Put sealant on the thick gaskets and bolt the manifolds to each head. Be sure to check the connection of the intake tubes at the center of the engine to be sure they are sealed. Next bolt the two wires and the clip to the left head. It would be a good idea to remove the thermostat at this point and check it. Inspect the gasket in the thermostat for breaks. Also, take the little hose running from the thermostat up to the coolant line. Mine was badly clogged from the use of Bar's Leak. Also note that the vent on the top of the thermostat is not to the atmosphere. It vents through the little hose to the coolant line above the thremostat. Replace the A/C compressor. Put a bit of oil on the surfaces that bolt together. This makes it easier to line up the bolts. Replace the air cleaner and attach the proper hoses. Don't forget to replace the electrical cord with it's wire lock. Be sure the oil drain plug is tight and replace the oil filter and 5 quarts of oil. Putting the coolant back in the system is a bit tricky. I jacked the front of the car as high as I could. Bentley says 16" but they don't say what the means. The wheels were about 10" off the ground. Remove the front radiator cover and the small plug on the right side of the radiator. Open the vent over the thermostat. Have a good supply of clean water or coolant. I used water as it was warm weather and I was not sure of the refill procedure. You will need about 4 qallons allowing for spillage. Fill the system by pouring the water into the expansion tank in the engine compartment. (Don't put any water in the reserve tank behind the license plate.) When you can't get any more in the system, start the engine and run it at 2000 rpm. The water pump will push liquid to the radiator and then back to the engine. This job should be done by two people. One to run from front, watching for water to come out the radiator, to back, watching the level in the expansion tank. The other person in the car should hold the rpm and watch the temperature gauge to be sure there is no overheating. After the radiator is spewing out water without bubbles, put the plug back in. Watch for hot water although there shouldn't be any yet. With the engine running, reach down and squeeze the large hose coming into the front of the thermostat. It should feel as if there is liquid in it. You well may hear a valve lifter clicking. This is apparently normal and will go away after awhile. Finally, take the van for a test drive and watch the temperature. Hopefully, all is well.