Engine boring - why might it be needed?

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

In the life of every car owner, sooner or later there comes a moment when his iron horse has exhausted all its resources and can no longer serve faithfully. Sometimes such troubles do without any serious procedures, but it also happens that boring the engine is the only way to bring it back to life. It happens when only the crankshaft journals are subjected to grinding. Such measures are taken in the event of a pressure drop in the lubrication system, as well as in the event of play in the lower head of the connecting rod. Still have to replace the liners.

But this is the most harmless case of engine repair using "surgical intervention". It happens that the engine cylinders wear out, lose their rounded shape and become oval. The longer axis has the direction of rotation of the crankshaft and the reverse of it, since it is in this direction that the greatest stresses on the metal are experienced, which means that it is here that it wears out the most.

Boring of cylinder blocks is a wrong, incorrect expression, since the block itself is not subjected to boring. This operation is carried out exclusively with cylinders. All of them have nominal and repair dimensions. If the wear is too great, thenboring to the nearest repair size. If the ovality is too large, then two or even three sizes are removed at once, which, of course, implies the replacement of pistons. The boring of blocks is carried out by experienced specialists on precision equipment, since the values here are comparable to 0.001 millimeters. It must be assumed that a simple person from the street will not be able to carry out such an operation. However, even a professional without the proper equipment is also unable to do so.

Another case in which engine boring may be required is a deliberate increase in displacement, namely tuning. Of course, 2.5 cannot be made from a 2-liter engine, but everything is made up of little things. Boring an engine is a fairly effective, but not a magical way. Here we need even more precise equipment, as well as the master himself - golden hands.

But sometimes everything is not so difficult and scary. It is possible that it was not the cylinders that were worn out, but the piston rings. Naturally, the former cannot avoid it either, but repairs can be limited to the latter, which, of course, is much cheaper.

In order to find out what needs to be repaired, measurements should be taken, which are called troubleshooting. To determine the wear of the rings, a feeler gauge is used, as well as a micrometer or caliper. They measure the thickness of the ring and the distance in the lock, that is, at the junction of its ends. This distance is called the thermal gap and is different for different engines.

The ovality of the cylinders is determined by the inside gauge, whichthe diameter of the cylinder is measured at six points: at three - along the length and perpendicular to the measurement axis. Troubleshooting is the only sure way to determine whether an engine bore is required or not. But here, too, there are small pitfalls that can cause a lot of trouble and problems. One of them is the inaccuracy of the measuring tool, so you need to select it carefully. If you do not carefully select the required one, then this is fraught with different sizes in the cylinders after boring, which means that the engine will fail.