Genuine Oldsmobile Omega Rod Bearing

Oldsmobile Omega Rod Bearing Parts Questions & Experts Answers

• Bearing Kit,Connect Rod
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  Q: What precautions should be taken when using Plastigage to check Rod Bearing clearances on Oldsmobile Omega?

  A:

  When working with Plastigage, three precautions are essential, first, before carrying out the test, it is advisable for all the surface of the Crankshaft and bearing surfaces that are in contact with the Plastigage to be free from any traces of oil and grease as the compound is soluble in oil; secondly, ensure that once the Plastigage has been fitted in the crankshaft or any other engine part that it does not get into contact with the crankshaft or the engine any other way Whenever an engine is undergoing overhaul, it is necessary to always check the bearing clearances and this applies to the used and the new bearings. The working of the procedure for the main and connecting rod bearings is analogous. First of all, fit the main bearings and caps into the engine block, make sure crankshaft and bearing surfaces thoroughly washed with oil, dirt, any other unwanted substance. Put a strip of Plastigage at the main bearing journal of the crankshaft and then fit each main bearing cap and fasten its bolts to the required tightness with the arrow on each cap pointing frontwards. Read and retain the bearing number stamped on the bearing, then , after tightening, dismantle each bearing cap and measure the width of the compressed Plastigage strip with reference to the scale exhibited on Plastigage envelope to understand the state of clearances for each bearing. As with most rotational equipment, if the Plastigage is much more flattened at the two ends than in the middle or, conversely, if the flattening is most pronounced in the middle, this is indicative of journal taper. It can be detected when all the Plastigage is removed, when the crankshaft has turned 90 degrees; then, check again the clearances with the Plastigage; by comparing the measurements made above with these latter, the eccentricity can be assessed. For connecting rod bearing clearances, it is necessary to install each piston/rod assembly and use such measure as Plastigage mentioned above. Also, it is possible to measure connecting rod side clearance at this time, if necessary. Any that are out of tolerance should be removed and replaced with bearings of the correct size; upper and lower bearings must always be replaced in pairs.