Pulley Alignment
05-21-2018, 09:33 PM
#1
Running Guns & Moonshine
Thread Starter
Pulley Alignment
I started taking down parts of the engine bay for a few projects tonight. I won't be able to get back to it again until the weekend.
One project is adding a gates rpm belt and replacing the factory tensioner and idler pulleys. This system has an LS2 ps pulley in place. The blower bracket is AA for a procharger. The P1sc sports a 3.8" pulley.
I will add pictures later tonight.
The car has a high pitch squeal which I located to the tensioner pulley using a stethoscope.
I believe I need to align all of my pulleys and do have a gates tool for this, which I will have to calibrate.
Here's the rub.
Hmm... pun was not intended.
The passenger side of the engine bay is coated with powdered belt material. The inside edge of the belt towards the engine has definitely been getting rubbed. Outer edge does not appear overly worn to my eyes, but again, I will post pictures. On the bracket spacer to the outside passenger side just under the blower drive pulley there is a splatter pattern of belt dust accumulated. To me, this suggests the drive pulley may be the one which is hungry. However, it could also be junk carrying up and over from the tensioner pulley and depositing there. The focal area of powdered debris is below the blower housing to about 4 or 5 o'clock. (Edit: further inspection with the flashlight shows the debris source is left of the blower, so it would seem to point towards the tensioner pulley. With the belt still intact, I am left to wonder if it can produce that much fine rubber particulate or if, as I have recently read with others, I may have to pay attention to the factory balancer. I will be sure to get in there from underneath with a flashlight over the weekend.)
No matter the case, I want to head this off before it becomes a problem and I want to get it done right on the first corrective attempt and enjoy the summer. I've read a lot on the forum and will continue to, but if you've diagnosed these issues before and have the voice of experience to chime in with I am at full attention.
Brett
One project is adding a gates rpm belt and replacing the factory tensioner and idler pulleys. This system has an LS2 ps pulley in place. The blower bracket is AA for a procharger. The P1sc sports a 3.8" pulley.
I will add pictures later tonight.
The car has a high pitch squeal which I located to the tensioner pulley using a stethoscope.
I believe I need to align all of my pulleys and do have a gates tool for this, which I will have to calibrate.
Here's the rub.
Hmm... pun was not intended.
The passenger side of the engine bay is coated with powdered belt material. The inside edge of the belt towards the engine has definitely been getting rubbed. Outer edge does not appear overly worn to my eyes, but again, I will post pictures. On the bracket spacer to the outside passenger side just under the blower drive pulley there is a splatter pattern of belt dust accumulated. To me, this suggests the drive pulley may be the one which is hungry. However, it could also be junk carrying up and over from the tensioner pulley and depositing there. The focal area of powdered debris is below the blower housing to about 4 or 5 o'clock. (Edit: further inspection with the flashlight shows the debris source is left of the blower, so it would seem to point towards the tensioner pulley. With the belt still intact, I am left to wonder if it can produce that much fine rubber particulate or if, as I have recently read with others, I may have to pay attention to the factory balancer. I will be sure to get in there from underneath with a flashlight over the weekend.)
No matter the case, I want to head this off before it becomes a problem and I want to get it done right on the first corrective attempt and enjoy the summer. I've read a lot on the forum and will continue to, but if you've diagnosed these issues before and have the voice of experience to chime in with I am at full attention.
Brett
Last edited by Tusc; 05-22-2018 at 12:04 AM.
05-21-2018, 11:59 PM
#2
Running Guns & Moonshine
Thread Starter
05-22-2018, 08:34 AM
#3
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yeah that's more dust than you should be seeing in my opinion, are you having problems with the belt jumping or slipping in high boost?... it should be pretty evident what is out of alignment once you get the belt off and start shooting the laser, just use the balancer as a reference to get it all lined up... check Bret's sticky at the top of this forum for some good pointers
05-22-2018, 08:53 AM
#4
Running Guns & Moonshine
Thread Starter
No slop that I could tell. Though I noticed the belt is a k060923 from car quest which came new with this used kit. The correct belt per AA for my 3.8 is the 910 length.
05-22-2018, 08:54 AM
#5
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Location: Atlanta, GA
Posts: 10,426
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1,056 Posts
2020 Corvette of the Year Finalist (performance mods)
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does the belt seem loose?... how much adjustment do you have left in the tensioner?
05-23-2018, 02:07 AM
#6
Running Guns & Moonshine
Thread Starter
Going by the open slide area for the manual tensioner? I'd say it was at 2/3.
05-27-2018, 02:22 AM
#7
Running Guns & Moonshine
Thread Starter
Busy weekend. One great show today, and then a private tour of a friend's shop and budding gun dealership. Not a bad day!
I got back and fiddled with the alignment tool. That took a lot longer than it should have to get it to shoot true.
So far, firing from the blower pulley to the blower idler and the crank pulley, if the tool is aligned on the top of the 2nd ridge, the beam is hitting cleanly in the center of the second valley (between the first and second ridge) on both pulleys. Presuming the tool is true at this point, that means the bracket and idler are true to the crank, but the blower pulley is half a rib out of parallel towards the inside of the car.
Shim the blower pulley?
Before I modify anything, I'll break the rest of it down and get lines from both directions on each pulley in the morning and see where the rest of it stands first.
Edit: and now I come back to the tool in the morning and check the alignment and it is off just on the paper tool by a quarter inch to the left. As someone used to precision optics who can quite literally pick twigs off a swaying branch in the wind, this tool is infuriating me and my perfectionist tendencies.
Edit 2: The tool is finally calibrated again. I let it fall on its side on a rubber mat and that knocked the calibration out by a half inch at 3 feet and had to do it all over again. It seems to be steady. Still shooting the 2nd valley from the blower to the crank.
I got back and fiddled with the alignment tool. That took a lot longer than it should have to get it to shoot true.
So far, firing from the blower pulley to the blower idler and the crank pulley, if the tool is aligned on the top of the 2nd ridge, the beam is hitting cleanly in the center of the second valley (between the first and second ridge) on both pulleys. Presuming the tool is true at this point, that means the bracket and idler are true to the crank, but the blower pulley is half a rib out of parallel towards the inside of the car.
Shim the blower pulley?
Before I modify anything, I'll break the rest of it down and get lines from both directions on each pulley in the morning and see where the rest of it stands first.
Edit: and now I come back to the tool in the morning and check the alignment and it is off just on the paper tool by a quarter inch to the left. As someone used to precision optics who can quite literally pick twigs off a swaying branch in the wind, this tool is infuriating me and my perfectionist tendencies.
Edit 2: The tool is finally calibrated again. I let it fall on its side on a rubber mat and that knocked the calibration out by a half inch at 3 feet and had to do it all over again. It seems to be steady. Still shooting the 2nd valley from the blower to the crank.
Last edited by Tusc; 05-27-2018 at 02:52 PM.
05-27-2018, 03:39 PM
#8
Running Guns & Moonshine
Thread Starter
First observation is that the blower pulley appears to have some horizontal angularity.
When the tool was on "top" of the pulley, I got several readings against other pulleys. When I rotated the blower pulley and measured again, the readings were off by half of one rib - the difference from one centered ridge top to one centered valley bottom. This being across to the alternator which is some 24.5" distant.
I don't like how the base does not fit firmly into the rib grooves and has some slop to it. Most pulleys are too small for the bungie cord, so I just press down on the feet to keep them square.
Readings so far where target is 2nd ridge top:
HU to HU bracket idler - Inside slope of 2nd ridge
HU to Crank - centered in 3rd valley (when P1 pulley rotated 180*, it then read centered in 2nd valley)
HU to Alt - 2nd ridge top dead center, then 3rd valley when HU rotated
HU to PS - Inside slope of 2nd ridge
Alt to PS - centered 2nd valley
Alt to Crank - centered 2nd valley
Alt to HU - centered 2nd valley
Edit:
I realigned the tool once again. I am going to take a hammer to it when I'm done. If this were on a blaster, you'd be shooting like a Stormtrooper: everywhere but where you aim.
This time I got some interesting readings.
HU to Idler - 2nd ridge
HU to Crank - Valley between 2nd/3rd ridge.
HU to Alt - 2nd ridge
HU to Ps - 2nd ridge
Alt to Ps - 2nd ridge
Alt to Crank - Valley between 1st/2nd ridge.
Alt to HU - 2nd ridge
Interesting that pulleys from two separate brackets can line up on one another across as far as two feet, yet each to the crank is off by about half a rib at what I am guessing is close to 18 inches and not optimal.
I'll replace the oem idler and see if I can get some shots from the crank out while they are removed.
When the tool was on "top" of the pulley, I got several readings against other pulleys. When I rotated the blower pulley and measured again, the readings were off by half of one rib - the difference from one centered ridge top to one centered valley bottom. This being across to the alternator which is some 24.5" distant.
I don't like how the base does not fit firmly into the rib grooves and has some slop to it. Most pulleys are too small for the bungie cord, so I just press down on the feet to keep them square.
Readings so far where target is 2nd ridge top:
HU to HU bracket idler - Inside slope of 2nd ridge
HU to Crank - centered in 3rd valley (when P1 pulley rotated 180*, it then read centered in 2nd valley)
HU to Alt - 2nd ridge top dead center, then 3rd valley when HU rotated
HU to PS - Inside slope of 2nd ridge
Alt to PS - centered 2nd valley
Alt to Crank - centered 2nd valley
Alt to HU - centered 2nd valley
Edit:
I realigned the tool once again. I am going to take a hammer to it when I'm done. If this were on a blaster, you'd be shooting like a Stormtrooper: everywhere but where you aim.
This time I got some interesting readings.
HU to Idler - 2nd ridge
HU to Crank - Valley between 2nd/3rd ridge.
HU to Alt - 2nd ridge
HU to Ps - 2nd ridge
Alt to Ps - 2nd ridge
Alt to Crank - Valley between 1st/2nd ridge.
Alt to HU - 2nd ridge
Interesting that pulleys from two separate brackets can line up on one another across as far as two feet, yet each to the crank is off by about half a rib at what I am guessing is close to 18 inches and not optimal.
I'll replace the oem idler and see if I can get some shots from the crank out while they are removed.
Last edited by Tusc; 05-27-2018 at 08:21 PM.
05-27-2018, 08:33 PM
#9
Running Guns & Moonshine
Thread Starter
Shooting from the crank to the AA bracket idler I got a clean shot at the 2nd ridge.
Going from crank to PS, I got on the slope of the 2nd ridge into the 3rd valley.
From the look of it this time through, it seems like everything is within Gates' acceptable spec. At least according to this miserable laser line.
I can't express how much I just do not trust this junk piece of metal. The base is not flush with the ribs. I can nudge it either way. Fingers crossed?
Going from crank to PS, I got on the slope of the 2nd ridge into the 3rd valley.
From the look of it this time through, it seems like everything is within Gates' acceptable spec. At least according to this miserable laser line.
I can't express how much I just do not trust this junk piece of metal. The base is not flush with the ribs. I can nudge it either way. Fingers crossed?