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After getting through and explaining that the compressor measures correctly, part numbers used and the situation looks bracket related. They said to measure the crank pulley. They have had no issues with brackets unless someone didn't buy the spacer kit.
I have 20-134 and 21-2 fbody spacer kit and I've ran factory fbody accessories for 8 years. Pretty sure I have the right fbody crank pulley. Only thing I can think of is maybe my corvette tensioner isn't right.
It's in the grooves of the compressor. The tensioner is the problem. I now see the instructions say use corvette tensioner and underneath it says due to part change dayco tensioner no longer works. I ordered mine through work and they didn't stock the Delco tensioner so they found dayco one same day. Delco ordered for tomorrow. Dayco getting returned.
I had similar issues with my holley A/C brackets. I am also using the 6PK2499 belt.
My brackets are Fbody offset. Holley bracket on the passenger side and GM F-body bracket on the drivers side.
Pulley alignment looked great on mine when installed. Checking with a straight edge from the crank pulley, the pulleys still looked good.
BUT, the belt would run about 3/8"(forward) from true with the rest of the system. With RPM(5k) the belt come off.
Took a while, but I finally tracked it to the threaded hole in the tensioner that did NOT come from Holley. The threaded hole for the smooth idler pulley was threaded slightly crooked, causing the pulley to run slightly crooked, which was pushing the belt off the front.
I replaced the tensioner(same pulley), now everything runs great. No belt issues whatsoever now.
Good Luck, PM me if you need any other info, sounds like we have an identical system.
The gm tensioner is identical to the GATES tensioner difference being the gm part number is ground off.. so with the gm pulley it still runs the belt crooked. Tensioner not the problem.
I need a grooved pulley that's offset or my Holley bracket machined so the grooved pulley will slide further into the bracket to be in proper alignment. I even grabbed my fbody tensioner removed the pulley and it's the same as the new Vette one bearing number 6203LAX30 AND it fits the same way.. the grooved pulley sits farther away from the engine and the other pulleys
Last edited by the450r; Mar 13, 2017 at 03:44 PM.
Reason: More info
Correction I had a gates tensioner not the dayco. The gates is identical to the AC Delco tensioner. I was going g to try getting just a tensioner pulley. I don't think the Holley tensioner will be much different. The tensioner with the smooth pulley is in line with the accessories but the idler grooved pulley (that you remove from the tensioner) is sticking out too far.
My compressor measures the same as your pic. I called Holley and I seem to get the same person saying there's nothing wrong and it's gotta be my factory pulleys. If I had Corvette or truck pulleys the belt wouldn't even go on I've reordered all the brackets to make sure mine were machined correctly. So I got a gates laser belt alignment tool and it shows that it's off a half a groove. Which according to their instructions is acceptable if the pulleys are 6" away. Which they are. I have been running it that way. Everything was working fine until I was pushing it really hard and noticed it was smoking on closed throttle. The upper hose about blew off and the spring clamp shaved the belt down to 3-4 grooves. I double clamped the upper hose with a worm gear clamp and limped home and got a new belt on. Drove it last night and it shredded 2 ribs off the new belt driving 20-25 miles below 3k rpm. It was walking off the front. At the car show I slipped the belt back on deepest groove and limped home to get another belt. When I was in sight of home I tried 4k rpm driving. Open the hood and the belt is still in place. Kwik performance brackets may be my only shot. The idler is forcing the belt to run off the front of the compressor.
Your issue sounds very similiar to what I was dealing with. I thought that I had mine solved for the last several thousand miles, until about 4 hours after you posted a few days ago.
I too was having issues with it running crooked on the smooth tensioner pulley and walking the belt off the front of the compressor.
I found that I had a tensioner(Gates) with the bolt hole for the pulley that was tapped slightly crooked. I got the tensioner warrantied and my belt runs much better now.
Had given me zero problems in many months and many miles, until you posted. That afternoon, it walked the belt one groove. Mine makes a ticking noise when it is off one groove.
Without digging through the thread, are you running all the Fbody accessories? crank pulley, alternator, water pump and power steering pump in stock brackets?
If so, do you know what length belt you are running?
I am using a 6PK2499.
All 01 LS1 Camaro drive. Factory belt stayed on until I added the Holley bracket, compressor tensioner and idler. My idler sticks too far out and will keep the belt on for a few trips. I found turning hard like a 90 degree turn into a parking lot causes the belt to jump on the compressor pulley were it starts to cut the outside rib off. It's a gates k060984 belt. There is a difference in the instructions I received and the online version stating about a design change in the tensioner and to verify belt alignment. I have tried the recommended tensioner with the same results. Also noticing the dayco number that says no longer works looks identical and has identical casting numbers as the Holley tensioner I bought from speedway motors locally.
So I tired find a different idler pulley with different offset and found a 89009 which is a 7 rib idler. It's larger diameter so it put a little more tension on the belt and with the 6 groove belt on the inside of the tensioner it appeared to fix the alignment issue. I drove it 20-30 miles no issues. What I've found is aggressive turning causes the belt to come off so I tried going in circles in a parking lot. No issues. Until I turned on the AC and went around a roundabout a block from my house when I pulled back in the belt wasn't shredded but it was a groove off on the compressor and it was still in the inside 6 grooves on the idler. It looked like it was twisting the opposite way it as the compressors out to far. With the fbody grooved pulley it appeared to stick out farther than the other pulleys and pull the belt over the compressor. It is really odd because before the idler was running farther out than the compressor and when the belt came off it would come over the outside compressor groove and off a groove on the idler. This time it was only off the compressor. I took some pics of the 7 rib installed. Compared to the other pics it looks in line.
So Holley sent me different spacers that go between the compressor and the mount. The ones shipped where very thin. They sent a thick and thin. I put them in right before power tour. It seemed to help but I still had to pop the belt back on and it finally shredded on the way home. I tried a bigger belt. Shredded it too. I tried the laser alignment tool again now the compressor is too far out and it's trying to run the belt off the outer edge of the tensioner. So I removed one of the suggested spacers. Now I have 2 thicker spacers aka washers. This helped bring the compressor more in line with the crank and power steering pulley. The idler now appears to be farther out than the other pulleys.
Hey 450R,
I have something for you to try. It is working great on mine.
I am using all Fbody brackets with the Holley brackets and was having the problem of the belt going one groove off the front of the compressor, and always seemed to look like it was riding to far toward the radiator on the tensioner pulley. Almost off the front edge. I actually found a wider pulley hoping it would help this issue. I am also using the kit supplied shims at the pump to bracket.
This will seem very unconventional, but it's working.
The tensioner mounts to the Holley bracket with two bolts. I placed a spacer(washer) approximately 0.050" thick at the lower bolt between the tensioner and the Holley bracket. My shim thickness needs may differ from yours since basically we are compensating for manufacturing differences in the Holley brackets and the tensioner castings.
It completely changed how my belt rides on the tensioner pulley. It moved the belt placement at least 0.250". It moved the belt all the way to the back of the pulley.
I have not had any belt problems whatsoever(roughly 3k miles) since I installed this "shim". However, I think I moved the belt alignment a little too far, I intend to try different thickness shims.
The other option might be to have a tiny little bit milled off of the Holley bracket at the upper bolt because that would move angle the tensioner the same as putting a spacer at the lower bolt.
Did nay of this make sense, Or did I just confusethe matter?
My accessories are 01 fbody. I did try a 7 groove idler and that's when Holley support threw a fit. Because I modified it. I've went through about ten belts. I've contacted them 4 times and only have one response from them. With the same results yeah I'm trying other things. The idler still sticks out too far. The shims they sent me put the compressor out to match the idler. I have lined the compressor up with the crank pulley.
Mine had the idler in the right place, but the belt just rode way out toward the front on the idler because it was at a very slight angle, thus the faster it spun the more it wanted to push itself off the front of the idler pulley. By putting my small shim behind it, it changed that slight angle and the belt rides great now.
I'm using truck spacing but had an issue at first with mine. I had the the Dayco corvette tensioner at first which worked for about the first 75 miles or so and then it started riding forward just like yours.
At first it would just ride one groove over the front but would eventually shred the belt. You could see it riding forward on the tensioner so I knew that was the problem.
I then bought the AC Delco tensioner and it's been just fine now with no other issues and I'm driving the car quite a bit. Probably 1000 miles or so since I changed it.
I have the Holley bracket kit and am afraid to put it on for fear of having the same issue....if I had known about this problem before I bought the bracket kit, I'd have looked at other options.
Since Holley seems unresponsive to this problem, wonder if Toddoky could do something to get some help?? Maybe he could at least help get the right people involved to get this sorted out??
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