Thursday, 6 October 2011

8. Fitting the third piece.

We will now move on to fitting the third piece of the engine case.

Make sure the third piece is clean. First we will install the number 4 bearing into the case, the bearing is held by a retaining bolt. Take the third piece and screw in the bolt until its end is just visible inside the hole for the bearing in the third piece.

Bearing retaining bolt shown above where the bearing goes.

Bolt end just protruding at top of picture.

Bearing with guide groove and hole for retaining bolt to fit.

Coat the bearing surface with WD40 and a little engine oil and do the same in the case.
Line up the bearing and use the old bearing as a drift to tap in the new bearing. Try and keep the bearing even and drive in until flush with the case but no further. You should now be able to tighten the retaining screw without resistance. If there is resistance remove the bolt and check with a torch whether the hole in the bearing is lined up correctly.

We are now going to fit the oil pressure line which is the metal tube which is shown on the right hand side of the case in the picture below.

Oil pressure line fitted with barrel washers with openings correctly aligned

It is on the right hand side of the third piece and has two red rubber barrel shaped seals, one on each end.
Take the new ones out of your gasket kit and dip the ends of the oil pressure line in some oil and put one red barrel seal on each end. As can be seen from the photo the line has an "S" shaped end that curls around one of the oil lines on the case. The barrel seals have to be installed correctly with the opening of the one nearest the top of the third piece being visible and in the seal at the bottom, the hole is face downwards as shown in the photos. 
NB some early engines did not have this oil pressure line.

Next we will install the oil seals that fit into the third piece and  seal with the main case. They can either be fitted to the main case end or the third piece end. There are different numbers and arrangements depending on  the year of the engine.

I have illustrated 2 different arrangements in the photos below.

Late engine  after 1963 or so had an extra oil pick-up circled in blue. This used a different "O" ring seal which is in the gasket kit. The 2 larger and one smaller seals are circled in red.


Early case with 2 larger and one smaller seals, (circled)

Coat the seals with oil/stp mix and put into place. Now get out your paper gasket from the gasket set. there will be 3 different types. Choose the correct gasket for your engine and make sure it fits. if it is a little tight it can be soaked in warm water for a 10 minutes to soften it.
Apply Wurth flange sealant to the bearing surface of the engine and the third piece. Use a spatula to spread to a thin layer.
Carefully line up the gasket and fit over studs trying not to tear it! 
Give the crank bearing area a final clean and coat the area with oil/stp mix. Also apply this mix to the Crank gears and the cam gears. Turn the flywheel and repeat the process. You can use engine grease if you plan to store the engine for a long time.

Distributor Drive installation.

There are 2 ways of installing the distributor drive. The Maestro describes the approach where the drive is fitted before final fitting of the third piece. The second approach is where it is fitted after the third piece has been fitted.

Method 1.

Put the distributor drive into the case via the distributor drive hole before installing third piece. We now take the distributor drive and clean it off.  Lubricate it with your STP/oil mix and remembering to install the washer, put it into the distributor drive hole at the top of the case and pop it into position making sure it turns freely. Do not forget the washer at the base.

Look carefully at the top of the distributor drive. It has a groove that is offset.

The distributor drive shaft has a groove that is offset towards the blue side

Make sure that the narrow side of the distributor drive is facing towards the rear of the engine (pulley end) and that the slot is parallel with the mating surface of the engine. Then rotate it 45 degrees or 1/8 turn anticlockwise. This is then the correct position for fitting the third piece. 

Distributor drive shaft in starting position with narrow side facing rear and slot parallel to mating face of third piece.(blue arrows)  It is then rotated 45 degrees anticlockwise. 

We now have to ensure the engine is at top dead centre. 
Place your finger in the hole for the intake cam follower for number 1 cylinder. this is found at the front right of the engine.

Intake cam follower hole - pop your finger in and rotate flywheel clockwise.

Pop your finger in the hole and rotate the engine clockwise until you feel the intake cam follower moving your finger outwards. Keep turning until the motion of the cam follower starts to reverse or goes back the other way. At this point you will find that the rod of number one cylinder (the cylinder above the hole) will be at bottom dead centre. If it is at bottom dead centre it will be low in the hole, so continue to rotate the engine until the rod comes out to its maximum and this will be top dead centre. Make sure it is out as far as possible by gently rotating the flywheel back and forth. This is now top dead centre on the compression stroke.

Method 2

Fit the third piece as below.
Get the engine at top dead centre on number one cylinder as before.
Using the special tool to clamp the distributor drive. This is a VW tool and can be obtained from most VW/Porsche parts vendors.

Distributor drive puller next to drive

Distributor drive puller attached to drive.

Take a long bladed screwdriver and feed the distributor drive washer onto the blade. Hold it carefully close to the handle and put the blade of the screwdriver into the distributor drive hole in the third piece. Look closely to check the screwdriver blade is touching the hole deep in the third piece where the drive sits and when ready release the washer so it slides down the screwdriver blade and onto the top of this hole. The washer can be centralised by moving it gently with the screwdriver. You are now ready to drop the distributor drive into the hole using the tool. 
Make sure the cut out is parallel with the join in the case and that the narrow side faces the rear. Guide the distributor drive down the hole and through the washer until it sits in place. Release the tool making sure you do not rotate the drive and check the groove is parallel with the case join and the narrow side faces the rear (pulley end). This is now the correct position

Fitting the third piece.

Make sure oil seals line up and fit the third piece to the main case, carefully feeding over the studs and tap on with the palm of your hand.
If you now look down the distributor drive hole the slot in the distributor drive should be parallel with the join in the case where the third piece meets the main case.

Take the special 8mm spring washers (they have a smaller outside diameter than normal) and the 12mm nuts and use the best ones either side of generator stand and to the left of distributor hole as these are most visible.

There are 11 nuts and make sure the logos are on the outside. tighten down using a 12mm socket, starting in the middle and working around. check the crank rotates freely. 

Take your torque wrench and torque to 17 ft lbs (15-18 in workshop manual).

Torque each nut 3 times.

You have now fitted the third piece and set up the distributor drive.


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