Rover's Vikingship Overhaul of the six cilinder engine
part Four
Rover's Vikingship


This part of site is an attempt to organize and add to the web resources for the Rover SD1 to form a cohesive and easily usable guide for those of us without easy access to expert repair and/or advice. It is not offered in any way as a definitive source and we take no responsibility for any errors that may exist.

The Cilinderhead

Now the cylinder head, the inlet valve tappets and pallets and the exhaust valve pallets should have already been identified for reassembly. The valves can be removed after compressing the springs to release the split cotters, using 1 8G 106, and S352.
Note that the exhaust valves are fitted with two springs.
The head must be thoroughly cleaned. In particular carbon deposit, such as this, must be removed from the combustion chambers and the exhaust ports.
Next the valve guides, check them for wear by inserting a new valve and tilting it. If movement across the seat is excessive, replace the guide.
The guides are removed and refitted using S60A, S60A-1 0 and PD1 D-A3. Mount the tool on the top face of the cylinder head for removal and on the combustion face to fit the replacement. Coat the new guide with graphite grease before fitting.
Next the valves, replace any that are bent or badly pitted.

Carefully examine the springs for signs of weakness or distortion. They must meet the specifications given in the repair operation manual.
The valve seat inserts should have an inclusive angle of 89'. If necessary, reface the seats but only remove the minimum amount of material necessary to obtain a gas tight seal. Badly worn seats must be machined out and new inserts fitted.
You can now rebuild the head. The valves must be fitted with new seals.

Valve Clearance Adjustment

Next the valve clearances, start by fitting the old pallets in their original locations. Where a valve has been reworked, fit a thinner pallet.
Fit the inlet valve tappets to the carrier, they can be retained with petroleum jelly.
If precautions are not taken, it is possible for the carrier to distort during fitting, due to the uneven valve spring load. To minimise this possibility, rotate the camshaft drive gear to the 1 o'clock position then lower the carrier onto the head, taking care not to disturb the pallets. Draw the carrier into position with three bolts, each in the row of holes nearest the camshaft. To ensure that the dowel tapers and the carrier holes locate correctly, tap the carrier sideways with a soft headed mallet as the appropriate bolt is tightened.
Now using an open ended spanner on the camshaft hexagon, rotate the camshaft to fully open each inlet valve in turn. Take care not to damage the carrier casting.
The inlet valve clearances are measured between the tappets and the camshaft, and the exhaust valve clearances between the rocker pads and the camshaft.

The full sequence of measurements is shown here, for example, with number 1 inlet valve open. Measure number six inlet valve clearance and number four exhaust valve clearance. Make a note of each measurement as it is made. When your readings are complete, carefully remove the carrier, taking care not to disturb the pallets.
Now Measure each pallet in turn and make a note of your readings.
To each reading, add on the measured valve clearance; then subtract the specified valve clearance. This will give you the thickness of the pallets required. Where a valve clearance is already correct, no action is needed. Incidentally, if the correct pallet sizes are not available, it is permissible to use those from the Dolomite range. Fit the pallets you have selected check that the head mating surface is oil and grease free., then apply a continuous band of RTV Silicone compound to the carrier.
Fit the tappets to the carrier and as before, draw it into position with three bolts. Fit and torque tighten the remaining bolts when the carrier is seated on the head.

The head rebuild is now complete but before refitting it to the block, you must set the timing scale at TDC. This is done by rotating the crankshaft until number one piston is exactly at the top of its travel. Check it using a dial gauge.
Then adjust the timing scale to line up with the pulley timing mark.
Now rotate the camshaft to line up the drive gear and carrier timing marks and fit two dummy studs, 1 8G 1294, and a new gasket to the block. Since the introduction of the 2300/2600 engine, improvements have been made to the head gasket design. Always fit the latest type.
To prevent the valves fouling the pistons, turn the crank back 45o then lower the head into position over the studs.

Tighten the retaining bolts, in the correct order, return the crank to the TDC position, make a final check that the camshaft timing gear is correctly lined up; then fit the timing belt.
Correct belt tension is very important, set it using a torque wrench and a 3/8 in. drive socket extension. Rotate the bracket clockwise to achieve the correct tension; then tighten the bolts. To check that the belt is taut on the drive side, rotate the crankshaft at least once.
Now the ignition distributor, fit a new 'O' ring, check that the crankshaft pulley timing mark is still lined up with TDC then fit the distributor so that the rotor comes to rest at the number six firing position. Final adjustment of the ignition timing is critical and must be carried out after fitting the engine in the car.

Next, fit the inlet manifold and carburettors the thermostat and housing and the camshaft cover. If oil leakage between the carrier and the cover has been reported, apply a coat of RTV compound above and below the cork gasket.
Finally fit the exhaust manifold, the sump the transmission and any ancillaries that were removed.
The engine can now be installed in the car and filled with the correct grade of oil. Finally fill the cooling system with antifreeze mixture. Failure to use the correct mixture would lead to corrosion and a build up of sludge in the coolant passages. This would reduce the coolant flow and eventually cause overheating.
That completes the overhaul procedure.

You can also have a look to:
Oscar Bakker "The Sixes"

Six cylinder engine part one
Six cylinder engine part two
Six cylinder engine part three

Torque Wrench Setttings of the 6 Cylinder engine



© rwp june 2003