Timing belt tension rule of thumb

The spring is used even when bolt is tight, it actually does move the tensioner over time as belt stretches slightly, and holds it in place the rest of the time. Jun 14, 2011 · Location. a practical and approximate…. 0000524 x pulley PD (mm) x pulley rpm (24-6) where: m/s = 0. This will impact the overall performance of the engine and can result in damage. Carefully inspect the drive. Measure the span length “K” of your drive (See Figure 1). Bad engine performance: Also you can have a bad engine performance. Rule of thumb for V belt is it should deflect 1/64 per inch between centers. Fan Application. The expression’s exact origins are unknown, but its earliest known use was documented in the 17th century. •Design with large pulleys with more teeth in mesh. Incorrect belt fitting – if a belt has been incorrectly fitted or June 13, 2023 - I've just built up my first belt drive bike. A well-established rule of thumb is that the best tension for a v-belt drive is the LEAST tension at which the drive will not slip under peak load. Oct 1, 2014 · Manual. 3L Timing Belt Symptoms. 2) Cold engine, before it's started for the first time that day. ationFA/127-11A technical bulletin for engineers, contractors and students in the air movement and c. Oct 11, 2021 · A timing pulley is a type of pulley configuration that features teeth and pockets on the outside diameter of the pulley’s body. Using the deflection and an easy bit of statics gives us a direct calculation of the tension in the belt with the extra weight: tension = (1/2) * weight * sqrt ( (length/2)^2 + deflection^2) / deflection. Strange noises: The rattling and squeaking sounds can be a common problem if the timing belt tensioner has a problem. These teeth and pockets mate with a timing belt having the same pitch in a synchronous drive, preventing pulley-belt misalignment and ensuring smooth power transmission. T–50. the scale, and slide the small O-ring up against the barrel of the gauge as shown in The non-tensioned side of the timing belt doesn't matter - the amount of tension on it will change as the engine rotates, and the valve springs exert force at different points during the rotation on the cam, which will pull that belt more or less against the crank pulley. Jan 20, 2008. Step 2: Lay out the new parts. Because the main duty of the timing belt is to provide good alignment of the crankshaft and camshaft. Learn more. Under the hood. Uses the exact same sprockets, drive shaft, to. Timing belt pulley measurements from catalogue. Hang one small weight–say, 10-50 grams–in the middle of the belt. Over-tensioning a timing belt reduces its lifespan dramatically. Here is another approximate method. Only compatible with Mul. Belt drives are expensive, costing up to six to 10 times as much as a chain and sprocket cam drive, and three to eight times as much as a gear drive because of the machining required for the front engine cover. Mar 1, 1999 · Drive tensioning. The video below demonstrates the measurement and adjustment of the timing belt on one side of the Y-axis as an example, and the same procedure can be carried out for the belt on the other side of the Y-axis. The belt tension level should then be checked to make sure it is within manufacturer’s recommendations for new belts. 7 Slacken the two bolts which secure the timing belt tensioner and, using a large screwdriver, prise the tensioner to one side to relieve the tautness of the belt (see illustration). Start laying out the new replacement parts and check to make sure everything is correct. It must be able to withstand all the forces acting upon it (belt tension, weight of the conveyed goods, uneven floors, etc. On the belt, you don’t have enough the Dec 4, 2017 · Here is another approximate method. #10. 262 x pulley PD (in) x pulley rpm (24-5) V(m/s) = 0. TECHNICAL SECTION. Get a belt tension tool for like $20 from the supply house and like 5ft of string. 2? RULES OF THUMB FOR INTERMEDIATE DRIVES. When doing a timing belt, especially on a front-wheel drive vehicle, always get the car on jack stands and at a decent height. You don't have to take off the lower timing cover to set the belt tensioner, right below the motor mount there is a rubber plug in the timing cover that comes out, I believe the bolt that holds it on is a 14 mm, just get a shallow well socket and a 3/8" ratchet and loosen it up and then spin the motor to the prescribed installation tension. 3) 15° - 25° C (59° - 77° F) ambient temperature. The timing belt tensioner applies the correct amount of tension to a vehicle's timing belt so the engine can maintain appropriate combustion timing. Ensure that the selected tension gauge is suitable for the type and size of V-belts you are working with. Then I tried to engrave (not raster) the same 20mm square I cut before at 50mm/s and now Im getting Aug 11, 2023 · The back tension release comes mainly with a hinge and lacks traditional triggers, which leaves the archer with no other option than to rely on back tension to fire. So after a punishing three hour run over Altamont Pass out to Stockton and back-- about 100 miles for the day total. Do not include lead threads in “full thread engagement. ”. Jul 25, 2016 · Step 1: Park your vehicle and turn off the engine. ared to a standard drive unit (60%). #5. BELT TENSION The optibelt OPTIKRIK is used to simplify the measurement of the belt tension or the static strand force of a two-pulley drive equipped with V-belts, kraftbands and V-ribbed belts. It's not a spring tensioner like many hondas would have. Show more replies. Indulge me: using the same two fingers and about the same force to hold a cap of a bottle or a handle of a. The car ( 83 Auto "US" 238,000 miles) was making scary noises. if you can twist the belt around 45 deg. Noise from the engine: A worn-out timing belt can produce a ticking noise coming from the engine. Pry the tensioner away from the belt and retighten the tensioner adjustment bolt. The timing belt tensioner has an eccentric cam in the middle of it. So I tried to loosen the belts until I got perfect lines (3mm mdf 10mA/10mm/s), but now the belts are super floppy. If I were you, I'd be doing a timing belt job right now. Default values, see pages 8 and 9. A deflection tool is definitely best. Aug 29, 2018 · Min-E-Pitch: Timing Belt Alternative. Tip: Take a picture of the serpentine belt routing with your cell phone. timing belt tension rule of thumb. Tensioning the belt is often done during initial startup and periodically throughout its life Size of belt, size of pulleys, distance between pulleys, etc. If belt tension drops below. 170. Pretension prevents belt slack-side sagging and ensures proper tooth meshing. Installation Tension (kg) New Belts. This episode will continue discussing essential installment and setup steps, focusing specifically on Belt Tensioning. While you are in there, it is smart to just get a timing belt kit and replace all the pulleys and the belt. Poor drive alignment, improper belt tension and worn pulleys all contribute to early belt failure. Tensioning Tension for Optibelt Timing Belts The correct belt tension is of crucial importance for trouble free transmission of power, and for the achievement of an acceptable belt service life. Unfortunately, this is the tension in the belt when it is stretched by the weight, rather than the tension in the belt in its original Oct 29, 2011 · 1983 Porsche 928s. SECTION 10 BELT TENSIONING. 4). only and must be mounted accordinglyHas limited chain pull co. Try to adjust the tension of the timing belts on both plates to be the same to ensure better engraving and cutting results. i did mine last night with a pry bar, to get the 13mm bolt in, and tighted. Since the pulley sizes are known, use of Center Distance Sep 10, 2008 · actually this could be better specified. This will allow the belt to seat-in and run at sug. Aug 14, 2008 · The tensioner uses a thick silicone fluid with a gradual tension that take a few minutes to fully engage. In English, the phrase rule of thumb refers to an approximate method for doing something, based on practical experience rather than theory. Loosen the belt tensioner adjustment bolt. Reduce or increase the belt tension according to the measurement result until the static strand force is shown. Of course this isn't an exact spec but its a good rule of thumb to go by . •Use high quality machined pulleys to minimize radial runout and lateral wobble. the scale and slide the small O-ring up against the barrel of the gauge as shown in Figure 2. Without your cambelt, metal is likely to smash into other bits of metal, valves will bend, connecting rods will distort and flex, cams will grind and graunch… and when the noise dies down and the . Step 8. Installation Tension (kg) Used Belts. Aug 26, 2023 · The Murky Origins Of “Rule Of Thumb”. IIRC Honda at one point was using a specific weight hanging from the middle of the chain span, but they stopped giving that spec when people started changing the sprocket size… Maybe Ryna could do a quick experiment on his machines The timing belt is a simple strip of rubber and metal that makes sure that the engine's key moving parts are choreographed to millisecond accuracy. #3. As a general rule of thumb, you should plan on replacing the belt every 60,000 to 90,000 miles, or at least have it checked. Then download the browning app. Its the easiest and most effective way, no electric impact and most 1/2 air impacts are taking it off. Parts can range from $60 to $350 depending on the vehicle and whether the tensioner is OEM or aftermarket. This article covers the basics of timing Jun 7, 2001 · Belt pretension (initial tension), Ti, is the tension set by an adjustable idler pulley. Browse auctions. Jan 25, 2012. Stabbing at a deflection without also accounting for the length of the span doesn't paint the complete picture. Aug 19, 2023 · Yes; a timing belt can be too tight or loose. Suggested Tension (kg) Ranges. Never, ever, less than 1/4 inch as you are likely to damage something. I check for the belt being taunt when pushed on, you should not be able to rotate the belt more than 90 degrees on itself by rule of thumb but that seems too loose to me. A 20-hp drive running at 50 rpm at the output shaft of a reducer could have a belt tension To adjust vehicle’s tension, until the most proper tension is got, clockwise turn the bolt to apply tension on the belt. The belt will be on the front of the engine. But, at the end, it depends on how much force you put in doing the twist. Length of engagement is typically the same as guidelines in “Joint design. The deflection should be approximately 1/2 inch for every 12 inches of belt span. Oct 5, 2014. Most v-belt problems are due to improper tensioning. Jan 3, 2009 · Mar 19, 2009. May 26, 2016 · Welcome to the next installment in our Mech Minutes: Timing Belts & Pulleys series. But after reading MCargill's unfortunate post, and upon installing a quieter fan clutch, I am hearing what sounds like the timing belt and am concerned my belt also might not be tensioning. As someone posted just use a breaker bar and hit the starter, its loose. Remove the timing belt. According to Origins of the Specious: Myths and Misconceptions of the English Language, the phrase first appeared among the collected sermons of a Scottish preacher named James Durham. Because the tension of the belt is not at the required level. I know it is counter-intuitive, "if bolt is tight then tensioner pulley can't move", but never the less belt will loosen up over time with out the spring in place. between the cam sprocket and the aux shaft its tight enough. The stock timing belt must be changed every 18,000 miles to avoid breakage and a really messed up engine. The concentric pulley tensioner adjuster should have new bearings installed on a regular basis. 3. Learn How to Determine Proper Timing Belt Tension Mar 11, 2021 · Over-tensioned – if a timing belt is over-tensioned it can put a lot more strain on the timing belt. ng Belt TensionThis article discusses several methods for measuring the belt tension for V-belts commonly used in HV. The belt tension level should be The supporting structure must be rigid and stable. Force-Deflection Method 1. Note from Figure 26 that the deflection distance is always. Remove the pulley, followed by the timing belt cover lower half on later models. Almost afraid to pop the hood, it sounded like some kids were in there beating the engine with numchucks. 6 Using a stout bar to lock the flywheel ring gear. There may also be noises, such as droning or whining, and the belt may wear off faster. Sudden impact – if a mechanical system suddenly stops or mechanically jams it can cause the belt to break. For the total design of power transmission belt, we recommend our "Application designing program for belts", it can be downloaded at: The concentric pulley tensioner adjuster should have new bearings installed on a regular basis. Timing Belt tension question. 4. Do NOT attempt to tension the belt on a hot engine. Age: Even if you haven’t reached the recommended mileage, it’s essential to replace the timing belt if it’s more than five years old. On the belts, to test the proper tension. The "right place" is indicated by a notch and tab lining up Jan 29, 2024 · 1. Very similar to a BRM job mixed in with some ALH bits. If you are measuring a type AX V-belt, make sure your gauge is suitable for that kind of belt. •Keep belts tight, and control tension closely. Joined Jul 20, 1997 Location Wisconsin TDI B4 Passat Apr 22, 2010 · My Classifieds: 0. link wherever sprockets are located. Jul 29, 2016 · Threadlocker. Excess friction, heat, and slippage can occur when tension is too high. Aug 16, 2012 · 1) All timing belt tension readings are to be taken midway between the auxiliary & inlet cam pulleys. So my rule of thumb is: consistent wiggly line = belts are too tight, bigger wiggle in corners for example = belts are too loose. Sep 22, 2016 · Proof strength is about 7-10% lower than yield strength. V-belts operate on friction; the friction is multiplied by the mechanical advantage of the wedging principle. How you tension a belt at Nov 30, 2015 · The last thing you want is to have to rebuild your engine. Step 2: Open the hood and locate the serpentine belt. It consists of a timing belt, tensioner, and idler pulleys, which work together to maintain the correct alignment of the camshaft and crankshaft. My rule of thumb is every other timing belt change. May 8, 2023 · Tension guidelines: The correct tension on a V-Belt may vary depending on the specific application and manufacturer’s recommendations. 5. Often tension which is too high or too low results in premature belt failure. 7. Ex: center to center shaft distance 48" Belt deflection should be 48/64" or 3/4" The tricky part is measuring that deflection without a solid reference point at your belt. Calculate the static strand tension (Ts) per belt by the following formula: Apr 11, 2024 · 1. 1/64′′per inch of span length (for example, a 32′′span length would require a deflection of 32/64 or 1/2 inch). The best bet is to follow what the OEM specifies, but there are also generic tables to follow. Aug 31, 2010 · Calculate the deflection distance by: t/64 = deflection. Number of Ribs. When there is adequate length of engagement, start with a hole size that provide 65% thread engagement. The force “F” you apply should be what is Installation - Timing Belt Tensioning Guide | Pfeifer Industries timing belt tension rule of thumb - viroan. For this reason, your manufacturer will have recommendations as to how often your timing belt should be replaced. More impor- Apr 1, 2009 · All previous and new model Ducati’s requiring belt tensioning now will be standardized to the below specifications. Because the timing belt is needed to keep everything running in sync, any issues can lead to performance trouble. kyocera flat bottom drill Jan 1, 2010 · What is a good rule of thumb when adjusting the tension on the timing belt after the new one has been installed. Give it some time and turn the engine over by hand a few times to put tension on the belt and make sure the engine stays in timing. New belts should be at 110 Hz, rechecking the belts (used) should be at 99 Hz. A belt which is overtensioned can cause bearing failure. Jan 22, 2019 · What was wrong with the old motorcycle chain tension rule of thumb was the deflection was totally arbitrary, based on how much effort you put into deflecting it. All pulleys and rollers must be fitted at right angles to the belt running axis. 1 (one) inch and it needs to be tightened because it is likely to slip. Supplier of OEM parts!!! why does belt tension matter? Proper belt tension is a critical step when installing a belt. Unfortunately, this is the tension in the belt when it is stretched by the weight, rather than the tension in the belt in its original Jan 19, 2008 · 5+ Year Member. . The frequency scales inversely linearly with length. [2] Speed is computed using the following equations: V(fpm) = 0. Correct V-Belt tensioning is the single most important factor necessary for long, satisfactory operation. 2. com VG33E 3. A closer estimate can be obtained from the table below. 6). Feb 19, 2006 · Refer to the appropriate shop manuals for cam timing procedure and belt tension setup, then reset to the below tensions for service. 3), or a force to a positioning platform of a linear actuator (Fig. •Design frame/shafting to be rigid under load. Requires a plain chai. Remove the tension gage and read the force applied by looking at the position of the small O-Ring. Several other factors should be part of the equation when considering replacing a timing belt, including: Engine performance I: A poor running engine could indicate a loose timing belt skewing engine valve timing. Step 7. t · (z2 – z1) l = 2 + 2e + 1 4e t · (z2 – z1) π 2 [mm] Select belt type and find point of intersection on the calculation sheet for that par-ticular type. Torque, Effective Tension, Tight and Slack Side Tension During operation of belt drive under Jan 24, 2019 · Not a problem. Did I install the washer? Short of tearing the whole thing apart, what's the best rule of thumb for checking timing belt tension on a 40v 4. When you have the cam in the right place you tighten a 13mm nut. [1] [2] [3] This usage of the phrase can be traced back to the 17th century and has been associated with various trades where quantities were measured by comparison to the width or length of May 27, 2021 · Some manufacturers recommend replacing the timing belt every 30,000 miles, while others suggest 120,000 miles. Torque wrench. Dec 2, 2012 · The Ducati manual states to set the belts at 140 Hz, but it is wrong. A thumb release has a trigger but comes in a different design that allows you to hold the bow, whether a compound bow or even a crossbow, at full draw. 273. Model Belt tension spec for new belts upon replacement Belt tension adjustment settings for used belts when inspected value is determined to be 70 Hz or less All models: Jun 7, 2024 · V Belt Tension Rule Of Thumb, Alternator belt tension Sailboat Owners Forums, Timing Belt Design and Installation Suggestions: General Guide Lines Home 2024-06-07 Oct 29, 2023 · 2. I don't have a smartphone so can't use the Gates tensioning app. Nov 20, 2006 · As long as the engine turns in a CW direction getting the crank bolt off takes a few seconds. Unfortunately, this is the tension in the belt when it is stretched by the weight, rather than the tension in the belt in its original should not use "feel" to judge the correct tension of a belt. Honda Tensioner, Timing Belt Automatic. Jan 23, 2019 · Using the deflection and an easy bit of statics gives us a direct calculation of the tension in the belt with the extra weight: tension = (1/2) * weight * sqrt((length/2)^2 + deflection^2) / deflection. However, a general rule of thumb is that the belt should deflect approximately 1/2 inch (12. It will be very apparent if something is broken. Special care needs to be taken since you crack the fuel system and need to completely bleed all the air out. Now operate the belt drive for at least 72 hours. Measure the span length P. This force creates friction so the belt’s Sep 12, 2023 · 4. Rule of thumb. Use the Right Gauge for the Job. ). Points. At center of the span length apply a force F (using a belt tension gauge) perpendicular to the belt span, large enough to deflect the belt 1/ Nov 9, 2023 · A timing belt tensioner is a device that applies precise force against the engine’s timing belt to prevent slipping and maintain accuracy of the valve and piston timing. In conveyors it may also carry a load placed on its surface (Fig. Taxes and fees may be added to these prices. The timing belt ensures that the valves open and close in sync with the pistons, allowing for optimal air intake and fuel combustion. May 7, 2018 · The car will likely run (and maybe even run decently), but your timing will oscillate by a few degrees every rpm. The point where speed and width curve intersect gives the RULE OF THUMB definition: 1. Poor Engine Performance. Here are some recommended belt tension settings for different types of 3D printers: Cartesian printers: 50-70N (Newtons) of force. Under proper tension, the deflection should be about 1/64th the center distance. IMPORTANT: When checking and adjusting timing belt tension at the recommended scheduled maintenance intervals, if tension reading is less than 70 Hz (minimum allowed value on all Ducati motorcycles), reset belt tension as Feb 8, 2006 · TDI. 2002 Jetta GLS. I would say that in the longest span of the belt you shouldn't see more than 2-3mm play up and down. Step 6. 2016 BMW 1200 GSA, 2004 ST3, 2005 Multistrada 1000DS (Sold ), 2007 Monster S4RS Pearl White (Sold ), 1998 900FE #179 (Sold) riknull. A half-inch over a 12-inch span is not the same as it is over a 6-inch span. Using the deflection and an easy bit of statics gives us a direct calculation of the tension in the belt with the extra weight: tension = (1/2) * weight * sqrt((length/2 Apply Tension A-7 A-8 All v-belt drives must operate under proper tension to produce the wedging action of the belt against the groove sidewall. Jun 14, 2024 · At lower speed and higher torque, transmitting the same horsepower requires higher belt tension to prevent slipping (V-belts) or ratcheting (synchronous belts). Feb 12, 2023 · Here is a more detailed list of the signs of a bad or failing timing belt to look for: 1. To more accurately tension V-Belt drives use the Force-Deflection Method shown below. Tension calculator for Timing belt. This is on a 1996 Honda Accord 4 cylinder V-tec Submitted: 14 years ago. put the belt on and then loosened the 13mm the spring put tension on it and then tightened up the 13mm again. Iirc "rule of thumb" is 1/64th of deflection per inch of spacing between centers, force is determined by belt type v belt tension rule of thumb on sale manufacturers, find details about v belt tension rule of thumb manufacturers, supplier and wholesaler - Unibelt. Expect to pay around $90 to $150 for labor. 00508 x fpm (24-7) Step 6 Determine belt length The design layout may govern the determination of the belt length. The curve above the point of intersection gives the belt width b 0 [mm]. There's no rule of thumb Nov 9, 2023 · A timing belt kit is crucial for the proper functioning of an engine. Watch the previous video for keys to successful alignment, and episode 2 for more on how to diagnose symptoms of belt wear. Timing belts are one of the most important parts of the May 1, 2014 · Messages. Over time, the rubber in the belt can deteriorate, leading to potential failure. At its core, it uses a calibrated spring and a smooth-rolling pulley to supply steady 300 to 400 pound tension against the belt. A typical rule of thumb for the right tightness is able to twist the belt with a finger and thumb a 1/2 turn. They have a belt tension calculator that can't be beat. But from what I've read the newer Gates CDX Nov 9, 2017 · belt span tension ratios and the vector angles resulting from the drive geometry. Indulge me: using the same two fingers and about the same force to hold a cap of a bottle or a handle of a bucket Place the tension gage directly on one belt at the center of the span. What matters is the tension on the side with the tensioner pulley. And it feels resistance. Timing belt tensioners are usually spring-loaded to allow them to adjust as the timing belt stretches over time so that tension isn't lost, and are designed to be replaced at the same time the Nov 14, 2011 · Various belt lengths and pulley diameters are available to accommodate different applications and variations in belt tension. Drive tensioning can impose a load on the structure that supports the motor, reducer, and other driven equipment. That is on one side between the pulleys, of course. C applications. Press down with moderate force, but not so much that you distort the belt. The final step is to operate the belt drive system for a few hours, allowing the belts to stretch and seat properly in the pulley grooves. Push down on the gage until the large O-Ring lines up with the straight edge laid across the back of the belt pulley-to-pulley. ue arm brackets as a standard drive. Nov 22, 2022. Generally, around the 80,000 mile mark it is kyocera flat bottom drill Step 5. With the cover off, check for the free movement of all the idler pulleys and the tension itself. This will make it easier to reinstall the belt if you do not have a diagram of its routing. Step 3. Also, extra force will be applied to the tensioner and timing belt with each oscillation which increases the likelihood of skipping a tooth, and prematurely wears both components. Browse used cars A timing belt transmits torque and motion from a driving to a driven pulley of a power transmission drive (Fig. The formula I linked to takes length into account. Using an incorrect gauge can lead to inaccurate readings. By taking into account the tight- and slack-side span tensions (tension ratio) of the belt drive and the arc of contact (or “wrap”) between the belt and sprocket, belt pull calculations may return a value that is more conservative than OHL. Slide the large O-ring to the recommended deflection distance on. 👌 However, as a general rule of thumb, the tension should be tight enough to prevent any slack, but not so tight that it causes the motor to strain or the belt to stretch. The exact tension depends on specific drive information: the… Search used cars. Adjustable pulleys and rollers are only to be adjusted after the belt has been properly Jul 12, 2016 · Rule of thumb for setting v-belts in general: 1/2" inch of slack. All in all, not a bad job. For proper tension, I know I had to twist the timing belt no more no less than 90 degree on the long length. turn motor over by hand or using starter 2-3 revolutions; THEN check belt tension (90 deg turn) and belt tracking (middle of gear) ; go back and tweak tension a smidge *if needed* (dont loosen the 15mm too much so it will give some resistance) P. For example, the static drive belt tension between a 100-hp, 1760-rpm motor and the driven shaft can easily exceed 2500 lb. #1. Thread-Forming Screw Rules of Thumb. Check the belt deflection: Release the pressure and check the amount of deflection. uggested tension range, re-tighten belt to the installation tension. This is a specially designed line of belts that has a circular pitch based on pi, making it easier to have the right number of pitches for the application and having lower requirements for tensioning. Because of this I wrote a supplemental how-to at the end on how to run the output test as well as the basic settings Jan 22, 2019 · Using the deflection and an easy bit of statics gives us a direct calculation of the tension in the belt with the extra weight: tension = (1/2) * weight * sqrt((length/2)^2 + deflection^2) / deflection. a practical and approximate way of doing or measuring something: 2. Poor performance is a strong symptom of a failing timing belt. Dave. In most cases, timing belts Feb 5, 2018 · This V-belt tensioning method relies on a Pencil Gauge Tool and the mathematical standards laid out in this V-belt tensioning table. View related parts. Another timing belt alternative Berg offers are Min-E-Pitch belts. Mar 8, 2024 · The replacement cost of the timing belt tensioner can be anywhere from $150 to $500. Run belt for five minutes. [2] 6. Bando are very good May 8, 2023 · Press down on the belt: Use your hand to press down on the V-belt at a point halfway between the pulleys. A general rule of thumb is that tension can be estimated by measuring the deflection of the belt at the middle of the span. Jun 11, 2017. 7mm) when moderate thumb pressure is applied midway between the pulleys. Step 3: Raise the vehicle using a jack. You turn the center with a pin tool and that moves the pulley a little bit back and forth varying the amount of pressure the pulley exerts on the belt. kj dl rx lw th wk iy mq dk pl