Check the cover and the damper to assure they are in good order. The post-'67 covers use "distribution tubes" to transfer water from the water pump into the block - check to make sure these tubes are not rusted out and have good seals, replace as needed. At this time, the tubes can still be purchased new from GM, part number ###########. The front cover/water pump assembly fits together in the following order: the cover; the distribution tubes installed; an open waterpump gasket; the divider plate (bevel goes toward the cover); another gasket (whichever gasket matches the waterpump); and then the waterpump. It is acceptable to use RTV on these waterpump gaskets, but use it lightly to keep from having globs of it squished into the cover (which can later come loose and clog your radiator).

The old front seal can be pried out with a small pry-bar or a flat-bladed screwdriver. Place the cover on a smooth flat surface (such as a piece of plywood), place the new seal in place, use a block of wood on top of the seal, and hammer the seal flush into the cover. The face of the seal (the part that will be making contact with the shaft of the damper) needs to be lubricated before the damper is installed.

Use RTV to mount the "U" shaped gasket to the cover. Only apply RTV to the cover to ease the cleanup, should you ever have to pull the cover. Typically, there will be two studs, located directly below the waterpump location. Install these studs, and slide the cover over them. Install the lower two ### bolts, and the two ### bolts that go through the waterpump (you may have to remove these later, to install accessory brackets, but need to be installed now to assure the cover seals properly).

Check the damper to assure it does not have a deep groove worn into it at the contact point with the seal. Also, check for cracks along the keyway groove. The elastomer (rubber), between the outer and inner rings, should be flexible and without cracks or other damage. Take a minute to either scribe reference marks, or at least mark with a dab of paint, on the outer and inner rings - these will aid to determine if the damper has malfunctioned, should problems occur later on. {pictures}

Apply a thin coat of oil to both the outside and inside of the shaft of the damper, and slide it through the timing cover. Thread in the damper bolt & large washer through the center of the damper, into the snout of the crankshaft.

You will need to torque the damper bolt to 160 ft-lb torque. To keep the crank from rotating as you tighten the bolt, use a wrench wedged between the block and crank counterweights (as pictured). You will have to move the wrench to the other side of the crank when you tighten the flexplate/flywheel bolts.

This method can also be used to remove the bolts during teardown. Do not forget to REMOVE the wrench before installing the oil pan!

Installing Oil Pump & Pan

Oil Pump

Installing the pick-up screen into a new oil pump can be extremely frustrating. There are tools made specifically for this task, but they are very hard to find.

The more common method of installatioin is pictured to the left. It is best performed with two people and a bench vise. Carefully secure the pump in the vise. Now, place the pickup tube into the pump body, then place a XX/XX" opened end wrench on the ridge of the tube. Have your helper place a metal drift (small pipe or something similar will work) on the wrench (as shown) and hammer the pickup about half way in.

At this point, it is time for a test fitting. Install the oil pump, but do not bother with the oil pump driveshaft at this time. With the engine rotated upside down, drop the oil pan in place, but only use the side gaskets at this time. You are looking for about a ¼" of clearance between the pickup and the bottom of the pan. A piece of clay can be placed on the pickup before the pan is dropped on, and will squish down to show how much of a gap you have. Once you are satisfied with the gap, drive the pickup in the rest of the way. Typically, you'll notice that the pickup is very close (or touching) the bottom cover of the oil pump - this is the reason for fitting before driving it fully in.

Double check the gap of the oil pump pick-up to pan clearance at this time, as you won't have another chance. At this point, you need to decide whether you are comfortable with the frictional fit of the pickup in the oil pump, or if you want to braze or weld it. Many people cringe at the thought of welding on cast iron (the oil pump case is typically cast iron), but it will not be subject to much stress and MANY people have done this without problem. Likewise, many people have had no problems with the frictional fit, but a few have slid out. If you do braze or weld, be conservative. Not much will be needed, and you DO NOT want to overheat the pump. Some people remove the relief spring {located behind fitting "A", as pictured below} to eliminate any chance of getting it too hot and reducing it's tension.

You can now install the oil pump. It will come with a gasket, which does not need any sort of dressing or RTV. The difficult part of this task is fitting the pump and it's driveshaft in place - a little bit of thick grease at the connection will help hold these together.

The driveshaft will have either retaining tabs or a retaining ring/clip that will keep it from rising up and off of the locating dowel (B) on the oil pump drive flange. Look closely at the shaft, and you will see that only one end will fit over this locating dowel. If the dowel (B) is missing off of the pump, get another pump!! The shaft will not stay on the pump without this dowel.

NOTE: The driveshaft MUST be installed at this point!! If not installed, the retention tabs/ring will have to be removed, and the shaft carefully installed via the distributor hole.

Windage Tray

There is debate over whether windage trays offer any real benefit. My personal opinion is that the factory would not have bothered if they did not help! Some people prefer to drill additional "drain holes" in the bottom of their pans, to minimize the chance of oil building up on top of the tray. The tray will typically have a few holes already, and I would suggest matching the size of those holes, for those who wish to add more holes.

The purpose of the tray is to keep oil off of the crankshaft to minimize the contact between the crank's counterweights with standing oil. When that contact happens, the oil makes it harder for the crank to rotate (parasitic power loss) and the crank causes the oil to aerate (windage, where air is mixed in with the oil, which temporarily reduces the oil's ability to lubricate).

The factory windage trays mount via 4 bolts, which attach the tray to the #2 and #4 main caps. Additionally, the lower dipstick tube is located and held in place by the tray[picture]. If a tray is used and the lower tube is NOT installed, the dipstick will be routed BETWEEN the tray and the crankshaft, and the dipstick will soon end up wrapped around the crankshaft!!!

Snug down the 4 bolts, and then rotate the crankshaft for a couple of revolutions. You are checking to make sure that no moving parts come in contact with the tray. Trays sometime get bent or twisted before being re-installed, and NOW is the time to find and correct any problem!

Oil Pan

NOTE!! If no windage tray is to be used, then the lower dipstick tube extension should be installed now.

The above pictures show the two different lower dipstick tube configurations. Both types slide into the block mounted tube. The tube in the left picture is held in place by its bracket that bolts to the #3 main cap, and this style is ONLY used when you are not using a windage tray. The right picture shows the tube and the windage tray, which secures the tube in place. A lower tube MUST be used, or else the dipstick tube can become tangled with the crankshaft. If you ever hear of a Pontiac motor that "eats" dipsticks, it is because someone forgot to install the lower tube.

With the motor still upside down on the stand, drop the pan into place without the gaskets. Rotate the crankshaft at least 2 revolutions to assure that there is no interference between the crank/rods and the pan. Now, identify whether your oil pan & rear main will require the use of the cork seal, the 5-slot seal, or the 2-slot/1-pin seal. {pictures} Use the plastic retainers to hold the side and front gasket pieces to the oil pan, and you may use a light bead of RTV on the pan if you wish.

If using either of the rubber rear seals, install them with RTV on top and bottom of the seal. These rubber seals will interlock with the side seals.

If using the cork rear seal, it will mount in the groove on the rear bearing cap. There is a top and bottom, and you can tell by the bevels cut on the ends of the seal. The bevels will face the block when properly installed. I coat all faces of the cork gaskets. Have the oil pan prepared for installation, before you start working on the rear seal. You can probably get the cork seal to stick in the groove for a few seconds, but it is going to pop out! Be sure it is seating back into the groove as you gently lower the oil pan into place.

Install all of the oil pan bolts, but DO NOT tighten them beyond finger-tight at this time. CAUTION!! Do NOT over tighten the oil pan bolts or you will damage the pan and split the gaskets. There is a specific torque specification for the oil pan bolts {insert value} but most torque wrenches will not probably work at that low of a value. I have found that the force I can provide with a nutdriver, using one hand, provides sufficient torque. This technique should work fine for the vast majority of us.

Start with the middle bolts, and use a spiral pattern to tighten the other bolts. Make at least 3 passes to assure all bolts are equally tightened.

NOTE: Be sure that the oil pan drain plug is tightened.

page 5 (Bolting on Heads)...