Gear Installation

Camshaft Gear Installation
by Steven St-Cyr
 
Determining TDC for a Camshaft Gear
This actually happened to me in the process of a rebuild af an F-134 coming from a M38A-CDN1 Jeep. The camshaft did not have a reference mark. Thanks to the help of Don Norris I figured out a way of determining how to install the camshaft gear in the right position. Good luck.
These following steps are notcritical for now. Directions are given with crankshaft up.
1. Draw a perpendicular outward from the keyway.
2. Mark that tooth as 14; see Figure 1.
3. Count down clockwise 14, 13, 12 ... 3, 2 ,1, 0.
4. Mark that tooth as 0, small line in Figure 1. This is your aproximate TDC mark for now.
5. Install both gears as below on TDC.

Alternate Method
1. Cut a sheet of paperas in Figure 2 below, keeping the original corner square.
2. Determine TDC using steps above.
3. Place the corner right in middle of camshaft bolt hole.
4. Place one side of the sheet right in middle of keyway and in middle of 14th tooth. If your gears are correctly installed the other edge of sheet should pass right in middle of TDC mark of crankshaft gear.

Thanks to DonNorris and Steven St-Cyr for putting this together. -- Derek Redmond
Rebuilding an F-head Engine
Page 3: Installing the Valves and Camshaft
by Eric Lawson

Return to the Engine Rebuild Table of Contents.

Except for the tappets, all of the parts in this picture are new. Because this is a new cam, the tappets had to be reground. If the old cam is being reused and the tappets are still useablemake sure the tappets go back into their original positions in the engine.
 

These are the ends of the camshaft. At left is the timing gear end of the shaft.
The oil holes in the bearing journals should be checked to be sure they are open. The oil hole shown at left allows oil to flow between the camshaft thrust plate and the face of the camshaft. The hole shown at right allows oil to flowout the port to which the cylinder head oil tube connects.
 

From left to right: the woodruff key that goes into the slot on the camshaft, the timing gear spacer, the camshaft thrust plate.
The spacer washer should be about .006 inch thicker than the camshaft thrust plate. On engines that have been rebuilt several times, the camshaft thrust plate becomes worn. If the difference in thethickness of the spacer and the plate is correct, but the end play of the camshaft is too small, try placing the other surface of the thrust plate against the camshaft.
 

This picture shows the valve spring, the valve, the "Roto-Cap" valve spring retainer (bottom row, left) and the valve locks (bottom row, right).
When the valve spring is properly installed, the two coils that are closesttogether, toward the left in this picture, should be against the block.
The valve locks are tapered. The narrow end of the taper should be closest to the head of the valve. The Roto-Cap fits over the lock and holds the locks against the valve stem. The ridge in the locks engages in the grove in the end of the valve stem. The taper in the valve lock holds the Roto-Cap in place.
The Roto-Cap causesthe exhaust valve to slowly rotate as the valve opens and closes. This helps reduce carbon fouling of the exhaust valve and its seat.
 

The valve tappets are installed, in the same holes from which they were removed. Use lots of engine assembly lube on all surfaces that contact another metal surface.
The main bearing dowels have not yet been installed.
 

This photo shows the camshaft inplace.
 

Checking the end play of the camshaft. The thrust plate is bolted into position, the spacer washer is placed on the camshaft, the woodruff key is installed and the timing gear is placed on the camshaft. The smooth surface of the spacer washer faces outward. The side of the spacer that is shown in the picture faces the cam.
The timing gear bolt is used to draw the timing gear into...