I upgraded the alternator in my 2016 Honda CR-V EX with 2.4 L gasoline engine to an Apex 200 Amp at idle and 350 maximum at a somewhat higher engine RPM. This high output alternator comes with a smaller pulley on it so it spins faster to aid it it being able to make more current, and one of the recommendations is to install a slightly shorter serpentine belt to take up the extra slack it creates. It is recommended that the new belt be 1/2 inch to 1 inch shorter then the original.
The original is 56.5 inches long.
NAPA does not list any in the required shorter range, so I called Summit.
Summit list a 55.5", 55.84" and 56.2". Since the 55.84 is in-between the recommended range of 1/2 to 1 inch shorter that is the one I ordered.
The one they sent me is an ACDelco Professional part no. 19194127 K070553HD made by Gates, and it is a heavy duty serpentine belt.
When I put a 17mm wrench on the hex had stud to move the tensioner, the amount of slack in the original looks like something that is 0.66 inch shorter would go on without any problem. But when I try to put it on, there is no way it is going to fit. It ends up being too short to get it to go on all the pullies at the same time. I had the tensioner moved to so much that I could tell it reached a hard stop on movement and would not retract any further. I tried making the water-pump the last pulley that it went on because the belt rides on the backside for that pulley and there is no lip to have to go over. But still it is too short to get the last amount of the belt on. Regardless of what pulley I use as the last one for the belt to go on, it is just not long enough.
The original belt only has 32,000 miles on it, and works good enough for now, but I want to put a on a new slightly shorter belt to be sure the belt is plenty tight enough when I load down the new alternator to power the high-reliability 2200 Watt Mean-Well 12 VDC to 125 VAC inverter I will be connecting to it.
It took me a while to figure out why this new belt that is only 0.66 inch shorter will not go on. Along with the already 0.66 inch shorter difference, I am working with two other things that make the over-all length even shorter than the original. 1) the new belt is not seated (worn in at all) and 2) this HD belt is much thicker then the original. At first the difference in thickness would not seam to be something that can cause a problem, but because on most pullies the belt rides on the side with groves, and on the big pulley of the water-pump the back-side of the the belt is against the pulley the difference in thickness combined with the large radius of the water-pump pulley uses up considerable more length of the belt, resulting it the over all length being too short for it to fit.
The bottom line is that thicker serpentine belts such as HD belts, because they also have to ride on some pullies that are against the back side instead of the side with groves, result in more of the belt length being used up, and this leaves significantly less over-all length of the belt to fit on the rest of the pullies.
In this case the difference is enough to make it impossible for a slightly shorter but HD belt to fit on all the pullies at once.
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I am thinking of getting an original length serpentine but in a HD and let the reduction of length from back of the thicker belt going around the water-pump provide the reduction of length that this set-up requires.
I just though I would pass this along, so you know that if you use a new HD serpentine and it has to have its back-side ride on one or more pullies as most systems do. So you know to expect the over-all working length to come up shorter that what the listing for the belt says it is.
The original is 56.5 inches long.
NAPA does not list any in the required shorter range, so I called Summit.
Summit list a 55.5", 55.84" and 56.2". Since the 55.84 is in-between the recommended range of 1/2 to 1 inch shorter that is the one I ordered.
The one they sent me is an ACDelco Professional part no. 19194127 K070553HD made by Gates, and it is a heavy duty serpentine belt.
When I put a 17mm wrench on the hex had stud to move the tensioner, the amount of slack in the original looks like something that is 0.66 inch shorter would go on without any problem. But when I try to put it on, there is no way it is going to fit. It ends up being too short to get it to go on all the pullies at the same time. I had the tensioner moved to so much that I could tell it reached a hard stop on movement and would not retract any further. I tried making the water-pump the last pulley that it went on because the belt rides on the backside for that pulley and there is no lip to have to go over. But still it is too short to get the last amount of the belt on. Regardless of what pulley I use as the last one for the belt to go on, it is just not long enough.
The original belt only has 32,000 miles on it, and works good enough for now, but I want to put a on a new slightly shorter belt to be sure the belt is plenty tight enough when I load down the new alternator to power the high-reliability 2200 Watt Mean-Well 12 VDC to 125 VAC inverter I will be connecting to it.
It took me a while to figure out why this new belt that is only 0.66 inch shorter will not go on. Along with the already 0.66 inch shorter difference, I am working with two other things that make the over-all length even shorter than the original. 1) the new belt is not seated (worn in at all) and 2) this HD belt is much thicker then the original. At first the difference in thickness would not seam to be something that can cause a problem, but because on most pullies the belt rides on the side with groves, and on the big pulley of the water-pump the back-side of the the belt is against the pulley the difference in thickness combined with the large radius of the water-pump pulley uses up considerable more length of the belt, resulting it the over all length being too short for it to fit.
The bottom line is that thicker serpentine belts such as HD belts, because they also have to ride on some pullies that are against the back side instead of the side with groves, result in more of the belt length being used up, and this leaves significantly less over-all length of the belt to fit on the rest of the pullies.
In this case the difference is enough to make it impossible for a slightly shorter but HD belt to fit on all the pullies at once.
--------------------------------------------------------------------------------------------------
I am thinking of getting an original length serpentine but in a HD and let the reduction of length from back of the thicker belt going around the water-pump provide the reduction of length that this set-up requires.
I just though I would pass this along, so you know that if you use a new HD serpentine and it has to have its back-side ride on one or more pullies as most systems do. So you know to expect the over-all working length to come up shorter that what the listing for the belt says it is.
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