A/C compressor pulley/ harmonic balancer misalignment
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7th Gear
Joined: Jun 2025
Posts: 7
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A/C compressor pulley/ harmonic balancer misalignment
So here is the problem that I face:
back a couple months ago I upgraded my C6 ls2 2005 manual vet with a summit racing bracket racer SFI harmonic balancer and a milling high pressure oil pump, sprocket, and chain(+ a cam and a lot of top end engine components). I have heard rumors that the milling oil pumps add about 3mms of spacing to the harmonic balancer which is the problem I face now, the harmonic balancer and the A/C compressor don’t align.the initial problem was that somehow the harmonic balancer came loose to the point it was scary to even think about even though I followed the install instructions to a T (235 ft Ibs ARP bolt: 234-2503) which is why the A/C belt slipped off the first time. I retightened the harmonic balancer with a wrench and breaker bar to the point to where it feels like I’m about to strip out the crank threads (don’t judge because I’m moving states in about 2 weeks and don’t have the time to pull the steering rack to correctly retighten it) A/C pulley and clutch feel fine no noises, harmonic balancer is sucked up to the block and no wobbling at all. So the only other explanation is either the new A/C tensioner I got is faulty, I didn’t tighten the HB enough (probably have it at 400 ft ibs definitely over bolt spec),the A/C pulley went bad, or somehow the A/C compressor is loose. So here are some questions.
1. Can I space out the A/C pulley ?
2. is there a manual tensioner I can buy for the A/C belt?
3. Does the milling oil pump actually add 3mms to the HB ?
Unfortunately, I have to drive the car 27 hours so having no A/C is not an option. I need a quick fix not a long one, I’m pulling the engine after I move to my new house. And help or feedback is greatly appreciated.
back a couple months ago I upgraded my C6 ls2 2005 manual vet with a summit racing bracket racer SFI harmonic balancer and a milling high pressure oil pump, sprocket, and chain(+ a cam and a lot of top end engine components). I have heard rumors that the milling oil pumps add about 3mms of spacing to the harmonic balancer which is the problem I face now, the harmonic balancer and the A/C compressor don’t align.the initial problem was that somehow the harmonic balancer came loose to the point it was scary to even think about even though I followed the install instructions to a T (235 ft Ibs ARP bolt: 234-2503) which is why the A/C belt slipped off the first time. I retightened the harmonic balancer with a wrench and breaker bar to the point to where it feels like I’m about to strip out the crank threads (don’t judge because I’m moving states in about 2 weeks and don’t have the time to pull the steering rack to correctly retighten it) A/C pulley and clutch feel fine no noises, harmonic balancer is sucked up to the block and no wobbling at all. So the only other explanation is either the new A/C tensioner I got is faulty, I didn’t tighten the HB enough (probably have it at 400 ft ibs definitely over bolt spec),the A/C pulley went bad, or somehow the A/C compressor is loose. So here are some questions.
1. Can I space out the A/C pulley ?
2. is there a manual tensioner I can buy for the A/C belt?
3. Does the milling oil pump actually add 3mms to the HB ?
Unfortunately, I have to drive the car 27 hours so having no A/C is not an option. I need a quick fix not a long one, I’m pulling the engine after I move to my new house. And help or feedback is greatly appreciated.
