4.2.17. Installation to the place of piston rings


1. Before installation on the piston of new piston rings it is necessary to perform measurement of gaps in locks of piston rings as follows.
2. Spread out assemblies of pistons with rods and new piston rings so that each set of rings could be compared to the corresponding piston and the corresponding cylinder in the course of measurement of a gap and at the subsequent assembly of the engine.
3. Insert the top ring into the 1st cylinder and push it in the cylinder by means of the top part of the piston. It will help to install a ring in the cylinder perpendicular to cylinder walls. Establish a ring as it is possible closer to a cylinder bottom around bottom edge of an entrance of a ring. Keep in mind that the top and 2nd compression rings are not identical.
4. The edge of the shchupovy measuring instrument is applied to measurement of a gap in the lock of the piston end, the measured value is compared to the data provided in Specifications.
5. In case the gap is too small (in case of use not of the original spare parts Saab) it has to be increased, otherwise, during the work the ends of a ring can adjoin one to another that often is the reason of serious damages. Ideally it is necessary to establish the new piston rings providing the correct gap in locks. As a last resort the gap of a ring can be increased by very accurate grinding by a file (thin). Fix a file in a vice with soft sponges, put on a ring a file so that it the ends adjoined to file surfaces, and the slow movements remove a little metal from the ends of a ring. Be careful, piston rings are very sharp and, besides, can be easily broken.
6. In case of installation of new piston rings very little possibly that the gap in locks will be too big. In case at measurement it is revealed that the gap is too big whether check the correct set of rings by you it was acquired.
7. Repeat the procedure of check for each ring in the 1st cylinder, and then with all rings for the remained cylinders. Do not forget to put at the same time rings to the piston and a rod of the corresponding cylinder.
8. After measurement of gaps in locks of rings and in the absence of need of carrying out adjustment, a ring can be installed on pistons.
9. Install piston rings on pistons, using the same technology, as at removal of rings. At first establish the lower (oil scraper) ring and further rise up the piston. At installation of an oil scraper ring at first insert a dilator, then establish the lower and top rings so that both gaps in locks turned out on not the persistent party of the piston approximately on 60 ° one in relation to another. Make sure that the 2nd compression ring is established correctly, so, that the word "TOP" (top) will appear above. Establish gaps of the top and 2nd compression rings on the opposite sides of the piston over lugs of a piston finger. Remark: Always follow the instruction attached to a set of piston rings - various manufacturers can recommend various procedures. Do not mix the top and 2nd compression rings as they have various section.