HOW TO DISASSEMBLE AND REPAIR A PERKINS ENGINE STEP BY STEP (PART 2)73 / 07.06.2022
REPAIR A PERKINS ENGINE (PART 2)
The maintenance of Perkins engines is of utmost importance due to the need to extend their useful life, since their replacement is a very expensive investment.
In order for an engine to maintain its efficiency, and at the same time to preserve its value throughout working hours, the user must provide minimal care that will involve disassembling the engine from the machine to check the parts internally.
It is recommended not to touch any part of the engine if the user has no experience in basic auto mechanics.
Otherwise, you only have to follow the following steps to provide correct general maintenance to your engine, so that it works in optimal conditions.
At Maq Parts we have written a series of articles that will help you with all these procedures, this being the second part aimed at 3, 4 and 6 cylinder Perkins engines.
If you have not read the first part, we will leave you the link so that you can do so and you can continue with it without problems.
We will start from the scenario in which the engine is already disassembled from the machine and has been opened to extract connecting rods, pistons and cylinders, again we emphasize that if you have not read the first part where we explain this in detail, do so before continuing with the reading.
To perform all the procedures listed below, the user must master the following tools:
- Screwdrivers set
- Racket key set
- Dice game
- Heavy duty cable or C-clamps
- Rubber mallet or medium hammer
- Locking pliers
- Dial alexometer
- 5 fine bolt
- Wire cutters
- Voltmeter or multimeter
- Wall peen hammer
- Lever bar
- Feeler gauge
- Valve puller
- Car ramps
- Hydraulic jack
If you do not have skills in them, we recommend you go to your trusted mechanic to carry out general quality maintenance.
Once the engine has been disassembled and the bands, connecting rods, pistons and connecting rod caps have been removed the engine will only have the main block.
This block is the heart of the engine since it is where the internal combustion that produces the power that moves the machine takes place.
After a review with an Alesometer, it will be determined if the hub where the cylinders are fitted should be rectified in a workshop or the rings should be replaced, in either case the hub should be washed afterwards to prevent residues from affecting the cooling systems.
However, before washing the engine, some parts must be removed, starting with the mounting which are rubber covers located in the lower part of the engine.
PROCEDURES FOR CONTINUED ENGINE DISASSEMBLY AFTER PISTONS HAVE BEEN REMOVED
Step 1: Flip the motor over so the rubber caps are on top.
Step 2: We insert an awl or tip screwdriver into the center of the rubber caps or rubber mounting, going all the way through. These are featured on Perkins engines on the opposite side of the piston cover.
Step 3: When removing each one of the rubber mounting, it will be possible to determine their life time by observing their wear, the wear will be reflected with the presence of stuck rust shells and iron filings.
Step 4: Once the lower rubber mountings have been removed, we proceed to also remove the rubber mountings or covers from the rear of the engine, these are two of different sizes and can be removed in the same way.
The Perkins engine rubber mounting are unusable once they are removed, so they must be replaced with new ones. If you do not have the spare parts, you can contact our customer service at maqparts.com, where we can get you the best spare parts with deliveries at home throughout the European Union.
Remember that the objective of removing the plugs or rubber mountings is to be able to insert special brushes into the engine that help remove all the residues left by the maintenance that is being carried out, these can be dust, dirt, rust, filings of iron, lacquer, among other residues that can harm the bearings and the correct operation of the engine.
Step 5: General cleaning is carried out with special brushes and liquids made specifically for cleaning combustion engines. To find out the corrosiveness that each engine supports, consult the manufacturer's sheet and the model of your Perkins engine.
Step 6: After having cleaned the entire engine, we will proceed to blow the engine before installing all the clean parts, remember to perfectly lubricate the parts even if they are new.
Step 7: We begin with the assembly of all the pieces starting with the bearings, remember to check them well when placing them, any grain of sand could seriously impair performance since these pieces will be under a lot of pressure.
Step 8: We continue with the bedplates, these pieces are placed next to the bearings, it is recommended to put some grease on the bedplates so that they adhere to the hub and do not move when we place the crankshaft.
Step 9: We pour engine oil to lubricate the surface of the newly installed bearings, this way it will be easier to install the crankshaft.
Step 10: Place the previously cleaned and blown crankshaft very carefully on top of the bearings, carefully ensuring that it is perfectly aligned with each one of the benches.
In the case that any of the benches is not in the correct position or has been displaced when placing the crankshaft, we must move the crankshaft to give ourselves enough space, in this case always try to move it to the side where the metals fit, since If it rotates in the opposite direction, the bearings could become unstuck and the oil will leak out.
Step 11: Once the Crankshaft is positioned and perfectly aligned, we place the side bearing caps.
Step 12: Before installing the main bearing caps, try to oil it so that it does not rub too much with the crankshaft. Once placed we hit it with a rubber hammer to adjust it.
IMPORTANT NOTE: During this process, make sure to check the position of each cap well, remember that this was done in the first part when we recommend numbering or marking each cap so that it will be placed in exactly the same position.
Installing a cover in the wrong position can cause serious engine damage.
Step 13: We place the threads on top of the benches and tighten them with a socket wrench, but without tightening them completely.
Step 14: When we have finished tightening the cap threads, we proceed to oil the entire piece and repeat with each of the cylinders.
Step 15: Once all the caps are in place and oiled, now we proceed to firmly tighten each of the threads, trying to give the same tightening to all of them.
Step 16: Now that the covers and the crankshaft are perfectly placed, proceed to place the engine pistons.
Step 17: The pistons must be clean and must be placed in pairs, 1 with 4 in case of 4 cylinder engines and piston 1 with piston 6 in case of 6 cylinder engines.
Step 18: When the pistons are placed in each of the cylinders, we proceed to place the cylinder covers very carefully.
Step 19: The numbers of the cylinder covers must coincide with the bearings of their respective cover, for this it will be necessary to have previously marked them before starting with the disassembly of the engine.
Step 20: With the cylinder covers in place, we proceed to place the oil pump, this should be adjusted in the same way as the covers, tightening each thread little by little until all are well tightened.
Step 21: If the oil pump is already placed and perfectly fixed, then we proceed to place the engine cover called Carter.
Step 22: To properly adjust the Carter, we carefully proceed to tighten all the threads that hold it to the engine, this procedure must be done very carefully not to leave anything undesirable inside the hub and tightening each thread little by little.
Finally, when we have finished placing the threads of the Carter the motor will be completely assembled, now it is only a matter of putting it back in its place.
For this last step you will need a hydraulic jack to help you lift the heavy engine and place it right in position.
Remember that all these procedures should only be carried out when it comes to general maintenance of an engine, but it is not always necessary, if the engine has been in use for a short time, preventive maintenance will be more than enough.
If you want to know when to carry out preventive maintenance and corrective maintenance, we invite you to read the third and last part of this series of posts about how to repair and maintain a Perkins engine.