rather than deflection (inches or millimeters): (Deflection of belt) = (0.25)* (span Pretension prevents belt slack-side sagging and ensures proper Design 2110 timing belt tensioner only one. If your model has heater hoses attached to the water pump, loosen the hose clamps with a screwdriver and slide them back onto the hose. The timing belt tensioner replacement can cost between $350 and $550. Manufacturers employ various schedules and measures for timing belt replacement, but the rule of thumb is 60,000 miles, or 5 years, whichever comes first. Checking With A Timing Belt Tension The simplest method is to allow the belt to sag on the return side of the belt circuit (called a catenary). 5 My 00 FSM says used belt setting is 140 to 160 ft lbs. Went pretty smooth. The one on mine is set with a Kriket 1 at about 110 and never has ever made any noise. On 16-valve engines use two elements, but one of them - pass the tension is not involved. V-belts are tensioned from human strength by prying against the engine block onto the selected accessory (where the belt loops onto) with a pry bar while simultaneously tightening the bolt on the slide bracket. A bad tensioner will usually be accompanied by noise. 2. Since it doesn't work well on the high tension side, it's best to use only A = Distance between the centers of both pulley. #2. If you can create more than 1/2 of slack, then the timing belt needs to be tightened. Recommended [2] This noise could be some type of squealing or rattling coming from the timing cover area. Loose timing belt tensioning acts like a loosely-held piece of string, with a snapping action as in a high torque situation the string or timing belt will break because the added stress is more than the timing belt was designed to take. Messages. the correct tension on a V-Belt. On a test given to over 200 experienced maintenance personnel, only 1% tensioned a belt correctly using the feel method. Most were at 7%- 50% of correct tension. Rolling or prying a belt on a drive gives one of two results, both lead to shortened belt life. Rolling causes low belt tension resulting in low That is why it is controlled by GOV. In the first method, stop the drive, then cautiously touch the belt. Over tensioning shortens belt and bearing life. Timing Belt - Tensioning 1 Numerical Method (Force/Deflection) By measuring the deflection of the timing belt with a known force the required tension can be applied. 2 Sonic Tension Meter. The sonic tension meter provides the most accurate tension measuring available. 3 ContiTech - Mechanical Power Transmission Drive Design Calculator. Pushing on the belt does not work well, it can feel just right and be as low as 60. I usually tension until you can just twist the belt 1/4 turn. Location. Jan 30, 2007. The weight of the belt itself keeps the needed tension on the drive shaft. Belt temperature can be checked in two ways. Length of open belt drive = 2A + (D1+D2)/ 2 + (D1-D2)2/ 4C. For proper tension, I know I had to twist the timing belt no more no less than 90 degree on the long length. The belt tensioner has no automatic spring. Same ladder, but this time I added a pulley! If it isnt too hot, your hand can When the belt is too tight, it seems too tight when you press on it (if you can visualize that). 4 Remove the heater hoses from the water pump. The terms used in the above equation are stated as below, D1 = Pitch circle diameter of the bigger pulley. Short of tearing the whole thing apart, what's the best rule of thumb for checking Same ladder, but this time I added a pulley! The timing belt calculation can be done by considering its length. My goal is to make either a cheap lift alternative or cheap options to lift compressors Design of the rollers can be perfectly smooth and with shoulders, so as not shifted the belt during operation. My goal is to make either a cheap lift alternative or cheap options to lift compressors with available implements so that we can collectively save our backs! Thread starter RabbitGTI; Start date Jan 9, 2003; RabbitGTI Top Post Dawg. A scaled down block and tackle may be next on the list. Steps 1 Listen. 11-24-2013, 09:17 AM. Belt pretension (initial tension), Ti, is the tension set by an adjustable idler pulley. Check after jog start or 1-3 minutes of operation, at 8 hours, 24 hours, 100 hours and periodically thereafter are recommended. E.g; Toothed belt or chain = 1.0 Vee-belts 0.9 Flat reinforced rubber belts 0.8 Flat reinforced plastic belts Check the tension by twisting the belt with your thumb and forefinger, midway along the longest straight run between the two main sprockets. Printable View. 4. It is the Tip speed of the blades that becomes dangerous. I've tried in the past to set the deflection with a spring balance, a rule and much patience (like I was taught) but I've grown Timing belt installation should be a snug fit, neither too tight nor too loose. Once tension is released, the belt should slide off of the other pulleys easily. Joined Jul 20, 1997 Location Its on a 9000lb strap loop around 2 rungs. Tech Tip: Rule of thumb: catenary sag should be 50-100mm for 900mm between support rolls. While a taut string or timing belt can stand a strong pull. The timing belt tensioner maintains the correct tension on your timing belt. As a very general rule of thumb you ought to be able to twist the belt with maximum finger and thumb force through no more than 90 deg on the longest run of the belt. Belt Tension. 3. Serpentine belts are automatically tensioned by the belt tensioner. Remove the belt. 1. Timing Belt Tensioner Replacement Cost. Phil 1 - 7 of 7 Posts This helps keep the combustion cycle in your engine properly timed. This is the preferred approach for tensioning Flat-Flex. Its on a 9000lb strap loop around 2 rungs. Nov 2, 2007. at constant speed and tension and loaded to 12 hp. The rule of thumb (literally) is to tighten the belt so that when you press down near the center of the belt with a semi firm push, but not jamming down on it, it should deflect about 1/2". A failing belt tensioner may cause your timing belt to become loose or slip resulting in engine sluggishness or erratic RPMs at low speeds. D2 = Pitch circle diameter of the smaller pulley. Pulley Outside Diameter (mm): 60mm. a good rule of thumb to go by is, you twist the belt and if it twists past 90 degrees it needs to be adjusted. But, at the end, it depends on how much force you put in doing the Take a small nut on the end of a string and twirl it notice the pull then take 17,501. The gauge is really easy to use once you get the hang of it. MA, Mittelfranken.de Feb 17, 2015 #21 As long as the engine turns in a CW direction getting the crank bolt off takes a few seconds. Belt tension at steady state can be calculated as:(6.6)Tb=1.37fLg2mi+2mb+mmcos+Hgmmwhere Tb is the belt tension (N), f is regulation. TENSION LOSS OF ROLLED ON INSTALLED V-BELTS 0% 20% 40% 60% 80% 100% 1HR Correct Install (not rolled on) excess slippage threshold Rolled On best case Rolled On average 24 If the belt tension is correct, you should just be able to twist it through 90 degrees. The rule tells you to place a finger in the middle of the belts, between two pulleys, and firmly press down. Depending on what length of belt design drive system timing may be one or two rollers. When the timing belt tensioner seems worn, there is a need to replace it with a suitable one. If you can twist it more or less than this, the tension needs to be adjusted. Of course this isn't an exact spec but its a good rule of thumb to go by . lock down the center distance adjustments and recheck the sprocket alignment. [2] Wiggle the hose and pull it off of the water pump. Timing belt installation should be a snug fit, neither too tight nor too loose. The positive grip of the belt eliminates the need for high initial tension. Consequently, a belt, when installed with a snug fit (that is, not too taut) assures longer life, less bearing wear and quieter operation. Most of the time a belt will break due to a seized pulley or bad tensioner allowing it to contact the timing cover. Check tension frequently during the rst 24 hours of operation. Press the belt with your thumb until it deflects about 1/2 in. Tension the drive until you get a slight bow in the slack side when it is running. These old rules of thumb for drive The tensioner often gets replaced alongside the timing belt, so you may need to budget between $500 and $2,000 to get both fixed. If the belt reverses direction, the idler alternately operates on the high and low tension sides of the loop. As someone posted just use a breaker bar and hit The positive grip of the belt A simple rule of thumb may be used to assess the grip on any pulley, based upon a design grip () being achieved for a contact angle () of 180 ( Fig 2 ). Then place a straightedge across the top of the timing belt. At the center of the span length P apply force using a pencil style tension gauge perpendicular to the span length P (see below picture). When using a pencil style tension gauge, the deflection scale is calibrated in inches of span length. Went pretty smooth. If there is less than 1/4 of slack, its too tight and needs to be loosened. Passat TDI timing belt tension. As you have Good rule of thumb for checking timing belt tension? Clovis, CA. Ideal tension is the lowest tension at which the belt will not slip under peak load conditions. Once you find the specs, use the following method if the specs are in given in force units (lb etc.) 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