I just pulled my transmission and while removing it I noticed alot of end play in the crankshaft. So the technique for a car equipped with a Long or Borg & Beck clutch is merely to start the engine in neutral. driving....the problem again arrises when these loads arent Ideal clearance would be mid-point between these minimum and maximum clearances. Pry the flywheel back and forth to check the crankshaft end play. This bearing will need to be sanded to add the necessary clearance, and get within the specs. Note the arrow that points to the end to be sanded. Now we can measure the thrust clearance by first installing a dial indicator on the crank nose using a magnetic base. There’s a simple technique for installing and measuring thrust bearings. Excessive end play can also cause connecting rods to fatigue and break, and wrist pins to work loose and score the cylinders. That’s why it’s important to check crankshaft thrust clearance, which is the amount of clearance between the crankshaft’s thrust plate and the vertical surface of the main thrust bearing. Excessive end play is evident once the oil pan is removed. Checking and setting proper crankshaft end play is a vital engine-building step. Required fields are marked *. Sanding in a figure-eight motion, we will sand for a minute or so and then check our measurements. While there will always be some force on the crankshaft, too much crankshaft end play from these forces can lead to damage and the need to tear down the engine. "After the pinch bolt is loose then This may cost nearly as much as the price of a new crankshaft. correctly) and i used the following excerpt from an EMAIL of While there will always be some force on the crankshaft , too much crankshaft end play from these forces can lead to damage and the need to tear down the engine. Just like all other engine clearances, the thrust clearance is critical for proper engine performance. This prying is absorbed to some degree by the in my crankshaft and the health/condition of my thrust bearing. With the main cap in place lightly tap the crank from behind to align the two bearing halves. Dial Bore Gauge Tested, EngineLabs’ Blueprint Series: The Keys to Proper Block Align Honing. We’ve included a chart listing factory endplay dimensions for some of the more popular performance engines. Pingback: How to Check Crankshaft End Play (Video), Pingback: How to Polish a Thrust Bearing (and Why You'd Want to in the First Place! Also make sure the two halves are clamped as they sit in the engine – it’s possible to orient them incorrectly which will not produce the results you desire. Each engine family has slightly different specs for crank endplay, but the majority of engine families fall in 0.004-0.008-inch range. the flywheel back and forth to check the crankshaft end play. For this application, we pre-assembled the rear main thrust along with the Number One main bearing, dropped in the crankshaft, and installed the main caps with the studs lightly tightened. It, Features: Engine of the Week August 2020 Recap, Features: 10 Reasons to be a Diesel Mechanic, Components: Valves, Rocker Arms & Pushrods, Products: California Pony Cars Mustang Timing Chain Cover, Engine News: SSC Tuatara Crowned World’s Fastest Production Vehicle, Engine News: NASCAR Reinstates Kyle Larson, Diesel of the Week: Compound Turbo LB7 Duramax Engine, Service Issues on Ford 4.6L SOHC & DOHC Engines, Carburetor Tuning: A/F Mixture, Air/Fuel Equation, Cleaning Engine Blocks & Engine Cylinder Heads, Ticking, Knocking Noise Complaints: Ford 4.6L / 5.4L 3V Engines. However, for the true engine builder, assembly really is the easy part. Pry Crankshafts are generally among the most abused components in an engine. Before fully torquing the main studs, it’s necessary to align the two pieces of the thrust bearing. That’s why it’s important to check crankshaft thrust clearance, which is the amount of clearance between the crankshaft’s thrust plate and the vertical surface of the main thrust bearing. The It’s really important to do your due diligence during assembly, so in today’s video, Brian from Summit Racing will walk you through the process of how to check crankshaft thrust with a magnetic dial indicator deck bridge. To get to the bottom of the issue, the Automotive Transmission Rebuilders Association (ATRA), the Engine Rebuilders Association (AERA), the Production Engine Remanufacturers Association (PERA), the Automotive Service Association (ASA) and bearing manufacturers got together and came up with a list of possible causes and remedies for thrust bearing failures. For more information about ASE, visit the official ASE website at www.ase.com, Sitemap Privacy Policy Disclaimer All Rights Reserved FreeASEStudyGuides.com ©Copyright 2020. RENNLIST MEMBER who performed the same procedure on his 88s4. Most performance thrust bearings are now built with multiple small ramps that change the “height” of the thrust slightly so it’s important to measure in several areas to locate these ramps. Checking and setting clearances is all about stacking the longevity odds in your favor. 3. We then measure the overall thickness of the thrust bearing end to end using a dial caliper. Crankshaft endplay never seems to garner the same level of attention as say, rod and main clearance, but even with its somewhat limited attention, this is still a crucial area. The math now is simple...subtratct #1 If you’ve done your math correctly, you should have an endplay clearance of somewhere near 0.006-inch as the number to shoot for. The challenge for the engine builder is to anticipate problems before they occur. Add a few drops of machine oil like Marvel Mystery oil to the sandpaper. The generally accepted procedure is to clamp the two thrust bearings together with a hose clamp, making sure the thrust surfaces are aligned and flat. is .007" .....i left all the zeros out....darn higher Generally you may need to only increase the clearance by 0.002- or 0.003-inch, but you will be surprised at how much sanding this will require. far back as it could go towards the engine i placed the dial Often, each has blamed the other for the resulting damage. We show you how to do the job in this tech segment. Doug Anderson of Grooms Engines Parts Machining in Nashville, TN, says his company uses a micropolishing machine for polishing crank journals and thrust surfaces. If when assembling an engine you discover the clearance to be very tight, there is a simple way to increase the clearance. How to Install Connecting Rod Fasteners the Right Way. Aside from obvious causes such as dirt contamination and misassembly, there are only three things that generally cause thrust bearing failures. The spec for later engines is .0024" to .0076". This is crucially important since that oily slurry which is left over after sanding is ridiculously abrasive and we don’t want that going through the bearings. SSC Tuatara Crowned World's Fastest Production Vehicle, Dayco Expands Timing Belt & Water Pump Warranty Program to 125K Miles, California Pony Cars Mustang Timing Chain Cover, Fass Titanium Signature Series Diesel Fuel Lift Pump, AJPE 521 cid ProCharged Hemi Pro Mod Engine, Hendrick & Childress To Develop Common Chevrolet Engine, Motor Oil Additives Play a Crucial Role in Engine Protection. We pry back on crank using a long screwdriver, then zero the dial indicator and then pry the crank lightly forward to read the total clearance. are experiencing "Thrust \par Bearing Failure". Starting a cold engine (when most of the oil has drained from this area) with the clutch pedal on the floor places tremendous load on the thrust bearing. Worn thrust bearings occur in older vehicles with manual transmissions. spec for later engines is .0024" to .0076". about THRUST BEARING FAILURE and how to prevent it. We will safeguard your e-mail and only send content you request. We promise not to use your email address for anything but exclusive updates from the Power Automedia Network. We used wet/dry 400 grit sandpaper lubed with Marvel Mystery oil. This will ensure the thrust surfaces are even from the rear which is where all the force will originate. Alternatives may be to try a different bearing manufacturer to see if the clearance will improve although this is unlikely.