0302288 JOHNSON SCREW,Upper front,motor cover

1P3537 BORE GAUGING GROUPWhen reconditioning an engine, the bore size is the determining factor as to the necessity of honing the bores. If bores are worn .006 in. (0.15 mm) more than the standard size, the block should be honed. However, additional service may be obtained without honing if wear does not exceed the maximum wear limit of .0085 in. (0.216 mm).Before honing, inspect the bottom of each cylinder bore adjacent to the main bearing saddle or web. Some of the saddles may overlap the edge of cylinder bores enough to interfere with honing. Where overlap exists, machine a relief in the saddle to provide clearance for the honing tool. The radius of the relief must be concentric with the cylinder bore and .030 .005 in. (0.76 0.13 mm) larger than the bore radius. The relief extends .62 in. (15.7 mm) beyond the bottom of the bore, as shown. This provides adequate clearance for honing.
RELIEF IN SADDLES and CHAMFER AFTER HONINGWhen honing, check bore size at several locations in the length of the bore and around the circumference. Specifically measure at points perpendicular to the crankshaft centerline at locations .25 in. (6.4 mm) from each end and at center of bore. These three specific locations are primary gauge points during and after honing.
PRIMARY GAUGING POINTSWhen honing cylinder blocks, maintain the specified dimensional surface finish and crosshatch tolerances to obtain satisfactory oil control. The tolerances specified are virtually the same as those used for original bore finish at the factory, and can be obtained with an automatic honing machine such as the Sunnen CK-10. This machine has been evaluated and found to give satisfactory results.The Sunnen CK-10 machine is available from Sunnen Products Company, 7910 Manchester Avenue, St. Louis, Missouri, 63143.Due to the cost of suitable honing equipment, it may be more expedient to have the honing done by a shop equipped with a Sunnen CK-10 or equivalent. A list of these shops appears at the back of this manual.Transit Preparation
The following Steps can prevent damage to the block in transit to a shop.1. Completely disassemble, but do not clean block. The residual oil on the surface will prevent rust.2. Enclose the block in an industrial plastic bag and position it with the oil pan surface on a suitable wood pallet or equivalent. Dimensions of a suitable wood pallet are shown.
TRANSPORTING PALLET3. Cover the block with 1/2 in. (12.7 mm) thick plywood or equivalent, and band block to the pallet.4. Follow similar instructions when block is returned. To prevent rust, the block should not be cleaned after honing, the film of honing oil provides ample protection from rusting. If blocks are to be stored for any length of time, clean and anti-rust after honing.Cleaning Procedure
After honing is completed, and before assembling the engine, the cylinder block must be cleaned and prepared according to the following instructions.1. If not previously removed, the camshaft bearings must be removed to permit thorough cleaning of the oil passages. To remove the bearings, see the topic CAMSHAFT BEARINGS REMOVAL AND INSTALLATION.2. Using the 1P3565 Chamfering Group, remove the sharp corner at the bottom of the cylinder bores as shown. This is essential to prevent scuffing the piston skirts. The chamfer should be approximately 10° x .09 in. (10° x 2.3 mm).
CHAMFERING BORE
Avoid damage to the cylinder bore surface or any other parts.
3. Using the 1P5580 Brush Group and a strong detergent and water solution, clean the following areas of the block. A. Main oil gallery and supply passage. Use the 1P5572 or 1P5573 Brush and stroke several times while rotating the brush.B. Camshaft bearing oil passages. Use the 1P5571 Brush and stroke several times while rotating the brush.C. Cylinder bores. Use the 1P5574 Brush and stroke each bore for one minute while rotating the brush at 1000 rpm.
Incomplete cleaning will result in piston seizure or rapid wear of cylinder bores, pistons and rings. Only thorough rotary brushing with a strong detergent and water solution satisfactorily removes abrasive particles.
1P5580 BRUSH GROUP4. Thoroughly clean the cylinder block in an agitator-type cleaning tank. This type of cleaning should follow the brushing of the cylinder bores but is not sufficient by itself for cleaning.5. Coat all machined surfaces immediately after cleaning with engine oil (SAE 30). Keep the block covered to exclude dirt until assembled.Sunnen CK-10 Machining Data Main Bearing Bores
With main bearing caps installed and tightened to the torque given in the chart TIGHTENING PROCEDURE FOR THE BOLTS FOR MAIN BEARING CAPS. Check main bearing bore size using the 1P3537 Gauging Group. If the main bearing bore is not within 3.7075 .0015 in. (94.171 0.038 mm), replace the main bearing cap. It is necessary to line bore the replacement service caps. See the topic LINE BORING MAIN BEARING CAP.When installing main bearing caps on a reconditioned engine, use new main bearing cap bolts and washers.Main Bearing Cap Guide Width
Check the width of the main bearing cap guide. The guide width of a new cap is 6.5600 .0007 in. (116.624 0.018 mm). Replace main bearing caps that are less than the minimum width of 6.5580 in. (116.573 mm). It is necessary to line bore the replacement service caps. See the topic LINE BORING MAIN BEARING CAP.When installing main bearing caps on a reconditioned engine, use new main bearing cap bolts and washers.Line Boring Main Bearing Cap
When reconditioning a block, and one main bearing cap is replaced, line bore the replaced cap. If it is necessary to replace more than one cap, it is recommended that all of the main bearing bores be line bored. See the topic LINE BORING MAIN BEARING BORES.Clean bearing caps and saddles. Remove all nicks from pan rail. Plug oil holes in block with grease to prevent chips from entering oil passages.
CENTERING RINGS IN BLOCK
1. 1P2344 Centering Rings. 2. Oiler.Place 1P2344 Centering Rings (1), with oiler (2) up, on each side of the cap being replaced. For an end cap, place 1P2344 Centering Rings (1) in the