Excessive oil consumption indicates that the piston rings and/or valve guides need to be checked. Measure the compression in the engine cylinders to determine the amount of work required.
If the engine knocks or rumbles, the connecting rod and/or main bearings are likely to be damaged. Check the oil pressure by installing a pressure gauge in place of the oil pressure gauge and compare these readings with the Specifications. If the pressure is extremely low, the bearings and/or oil pump are probably worn out.
Loss of power, rough running, excessive valve clatter, noise, and increased fuel consumption also indicate the need for an engine overhaul, especially if they are all happening at the same time.
An engine overhaul procedure means restoring internal parts to the specifications of a new engine. During the bulkhead, piston rings are replaced, cylinder walls are repaired (cylinders are bored and/or honed). If cylinder boring was performed during engine repair, it was necessary to install new pistons. The main and connecting rod bearings are replaced with new ones and, if necessary, the crankshaft can be reground to restore the journals. The valves are usually serviced as well, as they are likely to be in poor condition. During an engine overhaul, other components such as the carburetor, distributor, starter and alternator can also be rebuilt. As a result, the engine should be like new, which can be operated without interruption for a long time.
Before starting the engine overhaul, carefully study the entire procedure, familiarize yourself with the requirements of the work. Engine repair is not difficult, but a lengthy procedure. Prepare all necessary replacement parts and special tools in advance. Most work can be done with normal power tools, although many parts require precise measuring tools to inspect.
Note: Do not proceed with engine disassembly until you have determined the necessary operations to be performed. Since the condition of the block is a major factor in determining the need for engine repair, never purchase replacement parts until you have fully inspected the block.
In conclusion, in order to guarantee maximum life and minimum hassle from a rebuilt engine, everything must be assembled with care, in impeccable cleanliness.