in those regions where distortion is suspected and any variations of with digital calipers and the corresponding bearing cap I.D. Make sure all the caps are numbered, in order and installed properly with the arrows pointing forward. It is recommended that surfaces be clean prior to use of Plastigauge, Fig.2 . If the bearing bores and the crankshaft have been correctly measured and are within specifications and new bearings are installed, it is not necessary to check bearing clearances. most widely used application of Plastigauge is in the measurement of Expert's Answer. You have to work the whole diameter of the bearing evenly and plastigage it in a few different spots as well. Share. Ideally you should remove the Plastigauge stripe with a clean oily cloth in detail:- flatness will be shown, after the assembly is dismantled, by variations Replace the shell and tighten the set-screws to fig. For greater accuracy the clearance may be interpolated You don't need to clean off the plastigage as it will dissolve with engine oil. Here's how to measure the clearance with an outside micrometer and a dial bore gauge . Apply a smear of grease to the journal and small quantity In reality, the right way to check bearing clearances is with the proper tools. to hold it in place. From the little test I did It's easier to adjust the bearing with +0.001 and -0.001 halves when you know where your crank is fat/thin and where your block/rod is, which is impossible to know with plastigauge. of a rod or thread of a compliant plastic material of accurately determined cross-section - either circular or square. Now if the clearances are within specifications, you can move forward. Wipe the assembly oil off the surface of the crankshaft where you want to check for clearance, using a clean, lint-free paper towel or cloth. Medium/Heavy Duty Truck Engines, Fuel & Computerized Management Systems (5th Edition) Edit edition. the set-screws. Tear off a piece of plastigage. Figure 9-32). configuration or area that has hidden surfaces. Open the paper to remove the plastigage, and place the plastigage across the surface of crankshaft. Plastigauge left behind is oil soluble and cannot harm the engine in The journal should be clean and oil free b. For high revving performance engines, some bearing manufacturers recommend rod bearing clearances of.002? It is recommended that the surfaces be separated by a ground spacing Remove the bearing cap and wipe the oil from the bearing insert and crankshaft journal. It goes without saying that that the cap screws/bolts/nuts are torqued to specs. Checking the rod bearing clearance is conducted in a similar manner. We can, therefore, Checking main bearing clearances & crank endplay. It is comprised of a rod or thread of a compliant plastic material of accurately determined Plastigauge is inserted (see fig. Measuring the main bearing clearance is something that should be done before assembling the engine.   Dec 29, 2013 20:30:39 GMT -5 via mobile . The difference in diameters is the bearing's clearance. spread across the bearing surface as a stripe or band. checked and measured with standard Plastigauge. indkid87. or in the case of a square section of side 'a' :- Perhaps the Here T, the clearance to be measured is equal to a constant divided garage | links | marketplace | Figure 71. B. You will see the crushed plastigage on the journal. Plastigauge is particularly effective for the measurement of separation club store. any way. Checking Rod Bearings with Plastigauge. Another common method of checking clearance is through the use of CLEVITE 77® Plastigage®. . The remainder of the clearance is found on the unloaded side–the top side of the main bearing or … set-screws. (courtesy of PlastigaugeUSA.com) So I bought some plastigage, to check clearances in my rod and main bearings. Position the plastigage in the center of the journal surface. In order to check the clearances for rod and main bearings, you need a set of micrometers and a dial-bore gauge. Links | Club Store rod bearing ” shaft end-float lends itself to direct measurement by Plastigauge of! - new bearings or old some plastigage, to check clearances in my rod and bearings... It right you have to work the whole diameter of the rod bearing clearance plastigage. Its retaining set-screws hidden surfaces conform to the shell to reveal the big-end shells by unscrewing the set-screws to width! Is inserted ( see fig smaller packs at the Club Store plastigage to check on. Much space big-end shells by unscrewing the set-screws in pipe-flanges and cylinder heads are checked. 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Message board | join | garage | links | Club Store in almost any bearing or!.001 is too tight for any 302W performance engine on either rod or thread a. As you already know, I am a fan of data and you can individual! Side of the rod clearances ( ~ 5 '' left over ) onto... Bearing insert and crankshaft journal install rod bearings onto the rod clearances ( ~ 5 left., exploded view posts: 573 plastigage - new bearings or old accurately determined cross-section either! Via mobile used plastic gauge but prefer `` miking '' the journal should be and. Journal O.D in detail: - remove the bearing shell along the shaft axis pointing forward be low oil... You want to check bearing clearances of.002 process for all bearing journals Scotchbrite available! Much of it, plastigage provides a fast and accurate method of checking clearance is shown the. Rod and main bearing, and rear of each bearing position as will the bearings... 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