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Cylinder block/crankcase - cleaning and inspection
Engine removal and general engine overhaul procedures / Cylinder block/crankcase - cleaning and inspection


Note: Always check first what replacement parts are available before planning any overhaul operation; refer to Section 1 of this Part. A Ford dealer, or a good engine reconditioning specialist/automotive parts supplier may be able to suggest alternatives which will enable you to overcome the lack of replacement parts.

Cleaning
1 For complete cleaning, remove the water pump, all external components, and all electrical switches/sensors. Unbolt the piston-cooling oil jets or blanking plugs (as applicable); note that Ford state that the piston-cooling oil jets (where fitted) must be renewed whenever the engine is dismantled for full overhaul (see illustrations).

11.1A Remove water pump . . .
11.1A Remove water pump . . .

11.1B . . . crankcase breather pipe and PCV valve . . .
11.1B . . . crankcase breather pipe and PCV valve . . .

11.1C . . . unbolt crankcase ventilation system oil separator . . .
11.1C . . . unbolt crankcase ventilation system oil separator . . .

11.1D . . . remove electrical switches/sensors such as crankshaft
11.1D . . . remove electrical switches/sensors such as crankshaft speed/position sensor . . .

11.1E . . . unbolt blanking plugs (where fitted) to clean out oilways . . .
11.1E . . . unbolt blanking plugs (where fitted) to clean out oilways . . .

11.1F . . . but note that piston-cooling oil jets (where fitted) must be
11.1F . . . but note that piston-cooling oil jets (where fitted) must be renewed as a matter of course whenever engine is overhauled

2 Remove the main bearing caps, and separate the bearing shells from the caps and the cylinder block/crankcase. Mark or label the shells, indicating which bearing they were removed from, and whether they were in the cap or the block, then set them aside (see illustration). Wipe clean the block and cap bearing recesses, and inspect them for nicks, gouges and scratches.

11.2 Felt marker pens can be used as shown to identify bearing shells without
11.2 Felt marker pens can be used as shown to identify bearing shells without damaging them

3 Scrape all traces of gasket from the cylinder block/crankcase, taking care not to damage the sealing surfaces.

4 Remove all oil gallery plugs (where fitted).

The plugs are usually very tight - they may have to be drilled out and the holes re-tapped.

Use new plugs when the engine is reassembled. Drill a small hole in the centre of each core plug, and pull them out with a car bodywork dent puller (see illustration).

11.4 The core plugs should be removed with a puller - if theyre driven
11.4 The core plugs should be removed with a puller - if theyre driven into the block, they may be impossible to retrieve

Caution: The core plugs (also known as freeze or soft plugs) may be difficult or impossible to retrieve if they are driven into the block coolant passages.

5 If any of the castings are extremely dirty, all should be steam-cleaned.

6 After the castings are returned from steamcleaning, clean all oil holes and oil galleries one more time. Flush all internal passages with warm water until the water runs clear, then dry thoroughly, and apply a light film of oil to all machined surfaces, to prevent rusting. If you have access to compressed air, use it to speed the drying process, and to blow out all the oil holes and galleries.

Warning: Wear eye protection when using compressed air!

7 If the castings are not very dirty, you can do an adequate cleaning job with hot soapy water (as hot as you can stand!) and a stiff brush. Take plenty of time, and do a thorough job. Regardless of the cleaning method used, be sure to clean all oil holes and galleries very thoroughly, and to dry all components completely; protect the machined surfaces as described above, to prevent rusting.

8 All threaded holes must be clean and dry, to ensure accurate torque readings during reassembly; now is also a good time to clean and check the threads of all principal bolts - however, note that some, such as the cylinder head and flywheel/driveplate bolts, are to be renewed as a matter of course whenever they are disturbed. Run the proper-size tap into each of the holes, to remove rust, corrosion, thread sealant or sludge, and to restore damaged threads (see illustration). If possible, use compressed air to clear the holes of debris produced by this operation; a good alternative is to inject aerosol-applied water-dispersant lubricant into each hole, using the long spout usually supplied.

11.8 All bolt holes in the block - particularly the main bearing cap and head
11.8 All bolt holes in the block - particularly the main bearing cap and head bolt holes - should be cleaned and restored with a tap (be sure to remove debris from the holes after this is done)

Warning: Wear eye protection when cleaning out these holes in this way, and be sure to dry out any excess liquid left in the holes.

9 When all inspection and repair procedures are complete (see below) and the block is ready for reassembly, apply suitable sealant to the new oil gallery plugs, and insert them into the holes in the block. Tighten them securely. After coating the sealing surfaces of the new core plugs with suitable sealant, install them in the cylinder block/crankcase (see illustration). Make sure they are driven in straight and seated properly, or leakage could result. Special tools are available for this purpose, but a large socket with an outside diameter that will just slip into the core plug, used with an extension and hammer, will work just as well.

11.9 A large socket on an extension can be used to drive the new core plugs
11.9 A large socket on an extension can be used to drive the new core plugs into their bores

10 Refit the blanking plugs or (new) pistoncooling oil jets (as applicable), tightening their Torx screws to the torque wrench setting specified (see illustration). Refit also all other external components removed, referring to the relevant Chapter of this manual for further details where required. Refit the main bearing caps, and tighten the bolts finger-tight.

11.10 Do not forget to refit all components - such as oilway blanking plugs
11.10 Do not forget to refit all components - such as oilway blanking plugs (three of four arrowed) - tighten fasteners to torque wrench settings specified

11 If the engine is not going to be reassembled right away, cover it with a large plastic bag to keep it clean; protect the machined surfaces as described above, to prevent rusting.

Inspection
12 Visually check the castings for cracks and corrosion. Look for stripped threads in the threaded holes. If there has been any history of internal coolant leakage, it may be worthwhile having an engine overhaul specialist check the cylinder block/crankcase for cracks with special equipment. If defects are found, have them repaired, if possible, or renew the assembly (see illustration).

11.12 Cylinder block, piston/connecting rod and crankshaft details
11.12 Cylinder block, piston/connecting rod and crankshaft details

1 Cylinder block/crankcase 2 Piston
3 Connecting rod
4 Big-end bearing shell
5 Big-end bearing cap
6 Big-end bearing cap bolts 7 Crankshaft

13 Check each cylinder bore for scuffing and scoring.

14 Noting that the cylinder bores must be measured with all the crankshaft main bearing caps bolted in place (without the crankshaft and bearing shells), to the specified torque wrench settings, measure the diameter of each cylinder at the top (just under the ridge area), centre and bottom of the cylinder bore, parallel to the crankshaft axis. Next, measure each cylinders diameter at the same three locations across the crankshaft axis (see illustrations). Note the measurements obtained.

11.14A Measure the diameter of each cylinder just under the wear ridge (A),
11.14A Measure the diameter of each cylinder just under the wear ridge (A), at the centre (B) and at the bottom (C)

11.14B The ability to feel when the telescoping gauge is at the correct
11.14B The ability to feel when the telescoping gauge is at the correct point will be developed over time, so work slowly, and repeat the check until youre satisfied that the bore measurement is accurate

11.14C The gauge is then measured with a micrometer to determine the bore
11.14C The gauge is then measured with a micrometer to determine the bore size

15 Measure the piston diameter at rightangles to the gudgeon pin axis, just above the bottom of the skirt; again, note the results (see illustration).

11.15 Measure the piston skirt diameter at right-angles to the gudgeon pin
11.15 Measure the piston skirt diameter at right-angles to the gudgeon pin axis, just above the base of the skirt

16 If it is wished to obtain the piston-to-bore clearance, measure the bore and piston skirt as described above, and subtract the skirt diameter from the bore measurement. If the precision measuring tools shown are not available, the condition of the pistons and bores can be assessed, though not quite as accurately, by using feeler gauges as follows.

Select a feeler gauge of thickness equal to the specified piston-to-bore clearance, and slip it into the cylinder along with the matching piston. The piston must be positioned exactly as it normally would be. The feeler gauge must be between the piston and cylinder on one of the thrust faces (at right-angles to the gudgeon pin bore). The piston should slip through the cylinder (with the feeler gauge in place) with moderate pressure; if it falls through or slides through easily, the clearance is excessive, and a new piston will be required. If the piston binds at the lower end of the cylinder, and is loose toward the top, the cylinder is tapered. If tight spots are encountered as the piston/feeler gauge is rotated in the cylinder, the cylinder is out-ofround (oval).

17 Repeat these procedures for the remaining pistons and cylinder bores.

18 Compare the results with the Specifications at the beginning of this Chapter; if any measurement is beyond the dimensions specified for that class (check the piston crown marking to establish the class of piston fitted), or if any bore measurement is significantly different from the others (indicating that the bore is tapered or oval), the piston or bore is excessively-worn.

19 Worn pistons must be renewed; at the time of writing, pistons are available as Ford replacement parts only as part of the complete piston/connecting rod assembly.

See a Ford dealer or engine reconditioning specialist for advice.

20 If any of the cylinder bores are badly scuffed or scored, or if they are excessivelyworn, out-of-round or tapered, the usual course of action would be to have the cylinder block/crankcase rebored, and to fit new, oversized, pistons on reassembly. See a Ford dealer or engine reconditioning specialist for advice.

21 If the bores are in reasonably good condition and not excessively-worn, then it may only be necessary to renew the piston rings.

22 If this is the case (and if new rings can be found), the bores should be honed, to allow the new rings to bed in correctly and provide the best possible seal; before honing the bores, refit the main bearing caps (without the bearing shells), and tighten the bolts to the specified torque wrench setting. Note: If you dont have the tools, or dont want to tackle the honing operation, most engine reconditioning specialists will do it for a reasonable fee.

23 Two types of cylinder hones are commonly available - the flex hone or bottlebrush type, and the more traditional surfacing hone with spring-loaded stones.

Both will do the job and are used with a power drill, but for the less-experienced mechanic, the bottle-brush hone will probably be easier to use. You will also need some paraffin or honing oil, and rags.

Proceed as follows:
(a) Mount the hone in the drill, compress the stones, and slip it into the first bore (see illustration). Be sure to wear safety goggles or a face shield!

11.23A A bottle-brush hone will produce better results if you have
11.23A A bottle-brush hone will produce better results if you have never honed cylinders before

(b) Lubricate the bore with plenty of honing oil, switch on the drill, and move the hone up and down the bore, at a pace that will produce a fine cross-hatch pattern on the cylinder walls. Ideally, the cross-hatch lines should intersect at approximately a 60 angle (see illustration). Be sure to use plenty of lubricant, and dont take off any more material than is absolutely necessary to produce the desired finish.

11.23B The cylinder hone should leave a smooth, cross-hatch pattern with the
11.23B The cylinder hone should leave a smooth, cross-hatch pattern with the lines intersecting at approximately a 60 angle

Note: Piston ring manufacturers may specify a different crosshatch angle - read and follow any instructions included with the new rings.

(c) Dont withdraw the hone from the bore while its running. Instead, switch off the drill, and continue moving the hone up and down the bore until it comes to a complete stop, then compress the stones and withdraw the hone. If youre using a bottle-brush hone, switch off the drill, then turn the chuck in the normal direction of rotation while withdrawing the hone from the bore.

(d) Wipe the oil out of the bore, and repeat the procedure for the remaining cylinders.

(e) When all the cylinder bores are honed, chamfer the top edges of the bores with a small file, so the rings wont catch when the pistons are installed. Be very careful not to nick the cylinder walls with the end of the file.

(f) The entire cylinder block/crankcase must be washed very thoroughly with warm, soapy water, to remove all traces of the abrasive grit produced during the honing operation. Note: The bores can be considered clean when a lint-free white cloth - dampened with clean engine oil - used to wipe them out doesnt pick up any more honing residue, which will show up as grey areas on the cloth. Be sure to run a brush through all oil holes and galleries, and flush them with running water.

(g) When the cylinder block/crankcase is completely clean, rinse it thoroughly and dry it, then lightly oil all exposed machined surfaces, to prevent rusting.

24 The cylinder block/crankcase should now be completely clean and dry, with all components checked for wear or damage, and repaired or overhauled as necessary.

Refit as many ancillary components as possible, for safekeeping (see paragraphs 9 and 10 above). If reassembly is not to start immediately, cover the block with a large plastic bag to keep it clean, and protect the machined surfaces as described above to prevent rusting.


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