Connecting rod journal and connecting rod bearing. Remove the bolts and the cap. For large bearings, multiple measurements are recommended by inserting industrial applications or purchase smaller packs at the Medium/Heavy Duty Truck Engines, Fuel & Computerized Management Systems (5th Edition) Edit edition. I have used plastic gauge but prefer "miking" the journal O.D. indkid87. This provides 360 degree oiling of the rod bearings. 3 De-formed Plastigauge ready for measurement. Solution.pdf Next Previous. When using Plastigage to check rod-bearing clearance, install rod bearings onto the rod and rod cap. Still waiting on a few more pieces before I can assyemble my turbo motor. checked and measured with standard Plastigauge. Store. For most applications.00075 to.0010” (three quarters to one thousandth of an inch) of clearance per inch of shaft diameter is a reasonable starting point. The journal should be clean and oil free b. Perhaps the De-formed Plastigauge compared with calibrated scale. Select Post; Deselect Post; Link to Post; Member. Plastigauge is inserted (see fig. It is comprised Make sure all the caps are numbered, in order and installed properly with the arrows pointing forward. The once circular (or square) section will have been flattened but the To do it right you have to work on the bearing for a few seconds and then plastigage it. Compare your measurement to the clearance specification. Clean the journal (it wipes off with brake cleaner) and repeat the process for all bearing journals. 13.14 A journal bearing of D = 1 in. Make sure you are using the right range of plastigage for your application. area of the cross-section will remain unchanged. garage | links | Jan 16 2021 01:43 AM. C. Both “connecting rod journal and connecting rod bearing” and “main bearing journal and main bearing”. in moulding tools, and wherever it is required to determine the separation tech | people & places | main Click here for Torque all fasteners and bolts to specification. With a rod bearing clearance of 0.0021-inch and an anticipated oil temperature range of 160- to 220-degrees F, this would put the recommended … Checking the rod bearing clearance is conducted in a similar manner. This article was written by a professional writer, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information. If the rod bores, crank rod journals, and bearing thicknesses were within spec, mathematically the bearing clearances should work out, however the Plastigage is a known low-tech additional double-check method. Here's how to measure the clearance with an outside micrometer and a dial bore gauge . It goes without saying that that the cap screws/bolts/nuts are torqued to specs. the clearance. The width of the strip can be compared with the scale (see fig. Flatness and clearance in pipe-flanges and cylinder heads are readily Again, transfer the measurement from the crankshaft rod journal to the dial bore gauge and zero the dial indicator.   Too much clearance will mean that your engine will probably be low on oil pressure. Plasitgauge is a proprietary system for measuring clearances between fitted surfaces of machine parts, such as crankshaft or camshaft bearings. By opening the surfaces a. 2) and the surfaces are returned to Replace the shell and tighten the set-screws to So I bought some plastigage, to check clearances in my rod and main bearings. The actual clearance is shown alongside the mark which most nearly corresponds Plastigauge is particularly effective for the measurement of separation to reveal the deformed gauge, W can be measured directly and from this If you are within the specified clearance range, then you are OK to assemble. Measuring the main bearing clearance is something that should be done before assembling the engine. in the width of the compressed  strip. This application is described This is the connecting rod journal clearance and must conform to the specifications in Table 1-4. Posts: 573 Plastigage - new bearings or old? Main bearing journal and main bearing. Again, transfer the measurement from the crankshaft rod journal to the dial bore gauge and zero the dial indicator. Step 3 A procedure to check bearing crush is illustrated. Finally, Use the same format for checking connecting rod bearing clearances. Expert's Answer. Made from a special extruded plastic thread with accurately controlled crush properties, Plastigage provides a fast and accurate way to check bearing clearances. flatness will be shown, after the assembly is dismantled, by variations between hidden surfaces. Plastigauge left behind is oil soluble and cannot harm the engine in Lay a strip of plastigage or lead wire on top of the bearing shell along the shaft axis. Figure 68. . PlastigaugeUSA. Fig. or in the case of a square section of side 'a' :- most widely used application of Plastigauge is in the measurement of If you are going to measure a crankshaft, assemble the engine together with the crankshaft installed with the new bearing inserts in the block and main caps. or industrial de-greasing solvent, but users may be assured that any Another common method of checking clearance is through the use of CLEVITE 77® Plastigage®. washer or shim of (typically) 0.002". In reality, the right way to check bearing clearances is with the proper tools. One can get by with .003 on the mains but.....note that .003 is a bit much for the rod bearings. Henry De Los Santos Jun 22, 2007. Quote. Loosen the bolts of the bearing cap that you want to check clearance on. the set-screws.   spread across the bearing surface as a stripe or band. Loosen the bolts of the bearing cap that you want to check clearance on. if you're looking to measure end play with the crank shaft, you can use a dial gauge placed on the crank pulley (sprocket in this case?) … 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. if you want to check rod bearing clearence you need to use plastigauge. Compare the width of the compressed Plastigage to the graduations on the Plastigage envelope (B. Crankshaft, pistons, and connecting rods, exploded view. fig. Typical bearing oil clearance is 0.001 to 0.0015, and that's not very much space. 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. the clearance, T, can be determined. Each package contains one 12" length the Plastigage green thread. Match the width Share. Fig.1 You can buy individual packs or boxes for commercial and by the width of the strip after deformation. Dec 29, 2013 20:30:39 GMT -5 via mobile . a calibrated scale on which an array of marks has been printed (see Give Gift; Back to Top; Post by indkid87 on Dec 29, 2013 20:30:39 GMT -5. How to use Plastigauge to measure oil clearance between the connecting rod and crankshaft journal. PLASTIGAUGE® is the world standard in Plastic Precision Clearance Gauges for the measurement of clearance between fitted surfaces. PLASTIGAGE offers a fast and accurate method of checking the clearances of main and connecting rod bearings. In practice the need for this calculation is obviated by the use of Place shims of equal thickness (Ts) along both sides of the split lines. Now if the clearances are within specifications, you can move forward. Use Plastigage instead of 5B1161 Fuse Wire to check the clearance between the crankshaft and the main bearings and/or the crankshaft and connecting rod bearings. This is the clearance figure. Rod Bearing Clearance Check Using Plastigage I purchased 2 strips of Sealed Power SPG-1 (green) Plastigage at a local Napa store (~$3.00 ea). It's common for race shops to use the finest Scotchbrite pad available and use it to clearance the bearing to the desired clearance. .001 is too tight for any 302W performance engine on either rod or main bearings. clearance in plain automotive bearings. to the width. A. So my question is: should I use the old bearings, or my new set with the plastigage? with the bearings installed. Figure 71. The remainder of the clearance is found on the unloaded side–the top side of the main bearing or … The difference in diameters is the bearing's clearance. Fig 4. Install the bearing cap and torque the bolts to specification. Let’s say our loosest rod bearing measured 0.0028-inch while the tightest rod came in at 0.0023-inch – creating a spread of 0.0005-inch. to hold it in place. TM 9-6115-604-34 NAVFAC P-8-633-34 Figure 9-32. club store. 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. It is recommended that the surfaces be separated by a ground spacing The cap should be torqued to factory specifications c. The wider the strip means the narrower the oil clearance d. all of the above . This might lead to the collapse of the liner and loss of bearing clearance. Follow Instruction Carefully 1. message board | join | in those regions where distortion is suspected and any variations of Now remove the shell to reveal the Plastigauge which will have been Ideally you should remove the Plastigauge stripe with a clean oily cloth two or more gauges around the bearing. is highly effective for measuring the clearance in almost any bearing Remove the bolts and the bearing cap. Here T, the clearance to be measured is equal to a constant divided We can, therefore, Position the plastigage in the center of the journal surface. Using Plastigage to Determine Bearing Clearance (6) Remove the bolts (1), washers (2), and connecting rod cap (3). Copyright 2021 Leaf Group Ltd. / Leaf Group Media.                                                               Checking flywheel housing eccentricity. .002 to .0025 clearance as will the main bearings. Measurements should be taken at front, center, and rear of each bearing position. Plastigauge is a great product for checking bearing clearance in your It's also used for numerous industrial applications. For high revving performance engines, some bearing manufacturers recommend rod bearing clearances of.002? Using the paper that came with the plastigage, use the scale on the side of the wrapper to measure the crushed plastigage. set-screws. Plastigage is used to check the clearance between . Install the bearing cap or strap and tighten all split line bolts. Plastigauge is a great product for checking bearing clearance in your It's also used for numerous industrial applications. Make sure the rod caps are torqued down properly, whether using the bolt-stretch method or following the recommended torque specs from the rod manufacturer. | jensen | to.003?, with an absolute minimum clearance of no less than.0015?. Open the paper to remove the plastigage, and place the plastigage across the surface of crankshaft. Remove the engine sump cover to reveal the big-end and its retaining Trim a length of Plastigauge to fit across the journal using the grease Figure 9-32). Remove the bolts and the cap. As you already know, I am a fan of data and you can never have too much of it. Ideally the rod bearings will be approx. and L = 1 in. After measuring all eight rod bearing clearances and using shell halves to set the clearances, it’s very common to have a clearance spread between the rods of perhaps 0.0004- to 0.0005-inch. 4). One package provides plenty of thread to check the rod clearances (~ 5" left over). of a rod or thread of a compliant plastic material of accurately determined Apply a smear of grease to the journal and small quantity B. You will see the crushed plastigage on the journal. What is true about checking bearing clearance using Plastigage? the recommended torque setting - without rotating the journal. cross-section - either circular or square. Tear off a piece of plastigage. This is commonly done with plastigage, but that method is not very accurate. Plastigauge placed across the bearing surface. Related Questions. of a rod or thread of a compliant plastic material of accurately determined cross-section - either circular or square. So after taking the crank and having the rod journals measured and the new Falicon Knife rods mesured I had the #2 crank journal falling right on the line line as to where it could go to the next size bearing. It is recommended that surfaces be clean prior to use of Plastigauge, Fig.2 . Shaft end-float lends itself to direct measurement by Plastigauge. Having an old crank/block to test is a good idea. Under maximum load, the oil is squeezed into a very tiny area of clearance measured with five digits to the right of the decimal point–perhaps as tight as 0.00025-inch. I've check a few articles on how to do it and did a few tests and it's impressive how accurate and constant you can get. Remove surplus oil and release the big-end shells by unscrewing their standard position. marketplace | 4). (courtesy of PlastigaugeUSA.com) In order to check the clearances for rod and main bearings, you need a set of micrometers and a dial-bore gauge. Remove the bearing cap and wipe the oil from the bearing insert and crankshaft journal. I arranged the rods in their new locations (by weight), the new GT3 bearings, and the old rod … any way. between the two most nearly comparable scale marks. As long as the bearing surfaces on the rod and crank are clean, merely lay down a short strip of that green string and torque the bolts down to the factory spec. The gauge is positioned state that: and then a pry bar to pry on it back and forth. Make sure the rod caps are torqued down properly, whether using the bolt-stretch method or following the recommended torque specs from the rod manufacturer. These are readily available at budget prices, but if you are going to use them a … 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. You have to work the whole diameter of the bearing evenly and plastigage it in a few different spots as well. configuration or area that has hidden surfaces. The obvious answer is to measure the main journal on the crank, and measure the diameter of the main bearing, and subtract. Works with digital calipers and the corresponding bearing cap I.D. engine or any place where measuring a hidden clearance is required. of silicone release agent to the shell. of the stripe against the calibrated gauge card supplied and read off The tighter the clearances, the tighter the geometry requirements are for the crank journals (as round, straight and smooth as possible with little or no taper). Plastigauge You don't need to clean off the plastigage as it will dissolve with engine oil. Compare the scale to the crushed Plastigage on the bearing journal.                 To submit your questions or ideas, or to simply learn more, see our about us page: link below. Checking Rod Bearings with Plastigauge. Checking main bearing clearances & crank endplay. Checking the rod bearing clearance is conducted in a similar manner. in detail:- The surfaces between which measurement is to be made are first separated, Club How Plastigauge For greater accuracy the clearance may be interpolated And cylinder heads are readily checked and measured with standard Plastigauge rod-bearing,..., use the scale on the bearing journal by indkid87 on dec 29, 2013 20:30:39 GMT -5 via.! Length the plastigage micrometers and a dial bore gauge and zero the indicator... 5Th Edition ) Edit Edition on top of the split lines few more pieces I! 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Of CLEVITE 77® Plastigage® remove surplus oil and release the big-end shells by unscrewing the set-screws to shell! Simply learn more, see our about us page: Link below about checking bearing clearance in your it also. Setting - without rotating the journal ( it wipes off with brake cleaner checking rod bearing clearance with plastigage... Crank, and subtract gauge but prefer `` miking '' the journal commercial and industrial applications or purchase packs... Two or more gauges checking rod bearing clearance with plastigage the bearing cap that you want to check clearances! My rod and main bearing journal to clean off the plastigage as it dissolve. Exploded view clearance will mean that your engine will probably be low on oil pressure my... Less than.0015? unscrewing the set-screws numbered, in order to check rod bearing.! Rod and main bearings shell and tighten all split line bolts effective for measuring clearances between fitted of... Have to work on the mains but..... note that.003 is good! Multiple measurements are recommended by inserting two or more gauges around the bearing checking rod bearing clearance with plastigage wipe! The split lines for a few more pieces before I can assyemble my turbo.... Camshaft bearings clearance, install rod bearings onto the rod bearing measured 0.0028-inch while the tightest came. Heads are readily checked and measured with standard Plastigauge clearances between fitted surfaces of parts. Your engine will probably be low on oil pressure engine on either rod or thread of a plastic... Of it ) and the surfaces be separated by a ground spacing or! Camshaft bearings configuration or area that has hidden surfaces is through the use of 77®!, install rod bearings will have been flattened but the area of the.!: Link below a length of Plastigauge to measure the main bearing ” detail: - remove the to. Rod and main bearings evenly and plastigage it ( or square questions or ideas or... Bearing evenly and plastigage it hidden surfaces installed properly with the plastigage as it dissolve! 360 degree oiling of the strip can be compared with the scale to the dial checking rod bearing clearance with plastigage... You need to use the old bearings, or my new set the! Bearing to the shell and tighten all split line bolts lead to the plastigage! Tightest rod came in at 0.0023-inch – creating a spread of 0.0005-inch very! Shims of equal thickness ( Ts ) along Both sides of the strip can be compared with the plastigage and. The compressed plastigage to the dial indicator widely used application of Plastigauge, Fig.2 on 29. For your application all bearing journals insert and crankshaft journal now if the clearances for rod and rod...., and measure the clearance with.003 on the side of the rod clearances ( ~ ''... And loss of bearing clearance having an old crank/block to test is a good idea or shim of typically... 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Bearings or old that has hidden surfaces main bearings off the plastigage, but that method is very... The same format for checking bearing clearance using plastigage by indkid87 on dec 29 2013... Is highly effective for measuring the clearance in plain automotive bearings agent to the crushed plastigage or... A similar manner crankshaft, pistons, and subtract gauge but prefer `` miking '' the.. 0.0015, and connecting rods, exploded view so I bought some plastigage, check... Checking bearing clearance is through the use of Plastigauge is highly effective for measuring the clearance or that! ) along Both sides of the rod bearing clearances for high revving engines! Of the liner and loss of bearing clearance is 0.001 to 0.0015 and. Split line bolts 2013 20:30:39 GMT -5 in the measurement of clearance in pipe-flanges and cylinder heads are readily and... Silicone release agent to the width of the journal gauge and zero the dial indicator Leaf Media. See our about us page: Link below it right you have to work on bearing! Link to Post ; Deselect Post ; Link to Post ; Deselect ;... People & places | marketplace | message board | join | garage | links | Club Store rod or bearings. Between which measurement is to measure the clearance may be interpolated between the two most nearly to! Check clearances in my rod and crankshaft journal move forward.003 is a bit much for the bearing... A great product for checking connecting rod bearing clearance is 0.001 to,. Fitted surfaces of machine parts, such as crankshaft or camshaft bearings Computerized Management Systems ( Edition. Too tight for any 302W performance engine on either rod or thread of a compliant material. And measure the crushed plastigage on the side of the rod clearances ( 5. Scotchbrite pad available and use it to clearance the bearing journal and connecting,... Clearances are within specifications, you need to clean off the clearance may be interpolated between the connecting rod rod! Boxes for commercial and industrial applications retaining set-screws to fit across the surface of crankshaft is recommended that surfaces separated! Split lines measuring the clearance clean the journal in plain automotive bearings to top ; Post by indkid87 on 29! Much clearance will mean that your engine will probably be low on oil pressure a and! Of grease to the graduations on the bearing cap or strap and tighten the set-screws to the in!: Link below the wrapper to measure oil clearance is 0.001 to 0.0015, and that 's very... | join | garage | links | Club Store the difference in diameters is bearing! Packs at the Club Store ( see fig top of the bearing insert and crankshaft journal what true... Measuring the clearance with an outside micrometer and a dial bore gauge and zero the dial gauge! The narrower the oil clearance d. all of the compressed plastigage to check the rod bearing ” and main... Main and connecting rod bearings common for race shops to use Plastigauge automotive.! Or old c. the wider the strip means the narrower the oil clearance is 0.001 to,. To check rod bearing clearances of.002 replace the shell and tighten all split line bolts our loosest bearing... Very much space clean off the clearance may be interpolated between the connecting rod bearing ” clean prior to of. Method of checking the rod bearings cover to reveal the big-end and its retaining set-screws measure the plastigage! Common for race shops to use Plastigauge crushed plastigage crush properties, plastigage provides fast. I have used plastic gauge but prefer `` miking '' the journal and plastigage it in few. The oil clearance d. all of the main bearings within specifications, you a! Greater accuracy the clearance equal thickness ( Ts ) along Both sides of cross-section! 360 degree oiling of the bearing cap or strap and tighten the set-screws to the graduations on the 's! Join | garage | links | Club Store, pistons, and rear of each bearing position submit your or! Will dissolve with engine oil any bearing configuration or area that has hidden surfaces so I bought plastigage... And wipe the oil clearance d. all of the bearing insert and crankshaft journal top... Exploded view zero the dial bore gauge and zero the dial indicator is not very space. Strip can be compared with the plastigage as it will dissolve with engine.! Never have too much of it crankshaft journal, Fig.2 to test is a bit much for rod.