Engine Reconditioning

Engine Reconditioning Slacks Creek – Brisbane Queensland

At UMR Engines we have fully qualified tradesmen using the most up-to-date machinery from the leading names in automotive engine reconditioning, including Serdi, Robbi, AMC, Berco, Rottler and Vane. Put these machines together with good machining practices and our qualified tradesmen and  you are ensured of high quality work at the most competitive price. We also offer specialised services such as Alloy Welding, Cast Iron welding, and Thread Repairs. We offer a unique lifetime workmanship guarantee.

Engine boring: Depending upon the finish the boring bar produces a minimum of .0025″ should be left to hone to a finished size.  When some performance engines are rebored oversize it is considered a good practice to bore and hone using torque plates. This helps minimise any changes to the bore sizes when the cylinder head is tensioned down. The safe oversize to bore an engine depends upon the design of the block casting. As an example 351 Cleveland blocks are only considered safe at .030″ oversize even though .040″ and .060″ oversize are available for engine reconditioning. Prior to boring a block the actual pistons being used have to be measured and checked for any differences. If the customer supplies the pistons it is advisable that consideration by the customer is given to the suitability of the pistons for the block being bored oversize. When differences occur from piston to piston we will select and mark each piston to suit each bore ensuring correct piston to bore clearance during final assembly.

Honing: When honing a bore it is possible to control what style of hone pattern is produced. Some engine rings require different hone patterns to ensure fast bed in and good oil control. as a general rule the desired angle of the cross hatch is 45deg to each other or around 25 to 30deg to the horizontal. Too steep of a cross hatch pattern will cause excessive ring rotation resulting in ring and piston ring land wear. Too course of a hone pattern will retain excessive oil resulting in unacceptable oil usage. The average surface finish should be between 10 and 25 microinches RA( roughness average measured as 1,000,000th.of an inch)so between 0.000010″ and 0.000025″

Surface grinding: Milling or surface grinding of cylinder head and cylinder block surfaces is important for total sealing of the head gasket. Surface finish is important and depending on the type of head gasket being used the surface finish should be in the range of 20 to 50 microinches RA. To measure the surface finish a profilometer is used. Bent overhead cam cylinder heads have to be physically straightened before surface milling to ensure correct alignment of camshaft journals.

Crankshaft Grinding: Crankshaft journals should be accurately measured to determine if the journals sizes are within the manufacturers specifications. When inspecting crankshaft it is important to note any surface finish problems. Diesel crankshafts and suspect petrol crankshafts should be crack-tested prior to grinding. Prior to grinding it is important to check availability of the required bearing size. When grinding cranks it is very important to maintain the correct radius size and shape as per the manufacturers specifications. Correct radius finish is paramount to prevent cracks developing during the engine service life. The crankshaft snout, keyways, flywheel flange, threads and seal areas should be checked before grinding.

Conrod resizing: Closing and honing a conrod back to the manufacturers specifications is a good alternative to replacing the con rods. Rods have to be checked for straightness and rod bolts replaced as required. A lot of late model engines use fracture/split rods that cannot be reconditioned. The new fracture/split rods are made from sintered powder metal and are forged with finished sizes requiring little to no machining saving at least 25% of manufacturing costs while improving performance by 10%.

Is your engine blowing smoke or using oil ?

Rather than completely reconditioning your engine, UMR may be able to repair your engine.
If your vehicle is just blowing smoke or possibly using excessive engine oil we have another option, that we call an “ In chassis Rebuild “

• Remove the cylinder head, sump & pistons
• Hone all cylinders
• Measure all pistons and piston bores to check for any excessive wear
• Measure the big end journals on your crankshaft
• Carry out a full valve grind and surface grind on your cylinder head/s
• Final wash engine
• Re-assemble with new piston rings, con-rod bearings, sump gasket, VRS Gasket set
• Supply new engine oil & oil filter
• New radiator coolant.
Some times all of the above work can be carried out while your engine is still fitted to your vehicle, saving time and money. This could save you thousands on unnecessary extra costs in removing the engine, or even boring the cylinder block to suit oversize pistons etc. The suitability of a refresh will be determined by the condition and wear internally once the engine is stripped. This repair is not always suitable but it is a possible alternative for you to consider when your budget does not allow for a full engine recondition.

Call us today and inquire about any engine reconditioning service or repair.