harmonic damper
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harmonic damper how do I tell if a harmonic damper has gone bad? I'm getting a nasty vibration whether I'm in neutral or what, so that rules out the stiffer tranny mount, or a driveshaft... I'm thinking either damper, or flywheel. Could anything internal causet his?
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Originally Posted by enisguy
how do I tell if a harmonic damper has gone bad? I'm getting a nasty vibration whether I'm in neutral or what, so that rules out the stiffer tranny mount, or a driveshaft... I'm thinking either damper, or flywheel. Could anything internal causet his?
Does the vibration get worse as you increase the RPM'S ??
I bought a Fluidampr for mine. I decided that the new rotating assembly was too much for the stock damper. The first thing I noticed was my header bolts were backing out. The 396 was a rough one but thought it was the nature of the beast. I haven't driven the car since I put on the new damper. Since you're running S/C, do you think maybe the crank pulley is just out of line just a tad or maybe one or two bolts are torqued too much? Was the bottom end balanced and everything when it was built?
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Originally Posted by dhdenney
I bought a Fluidampr for mine. I decided that the new rotating assembly was too much for the stock damper. The first thing I noticed was my header bolts were backing out. The 396 was a rough one but thought it was the nature of the beast. I haven't driven the car since I put on the new damper. Since you're running S/C, do you think maybe the crank pulley is just out of line just a tad or maybe one or two bolts are torqued too much? Was the bottom end balanced and everything when it was built?
(sorry for all the questions) Last edited by enisguy; Apr 19, 2004 at 12:23 AM.
Well when they built the bottom end, they should have "spun the parts" and made adjustments to balance out the assembly for smooth operation. If they just put it all in there without checking then it will be beating around in there and causing this vibration. BUT SURELY the machine shop balanced the thing. If the flywheel bolts aren't all torqued the same then it might cause a vibration but I wouldn't think it would be "nasty." I would take the belt and crank pulley off the S/C and go from there. See if it vibrates without the S/C running. BTW, shouldn't you be running like 11's?
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Well I would try everything in simplest order. I just have thought that the stock driveshafts on these cars are bad to be out of balance but you said it does it in neutral too so that rules that out but something to look at anyway (for later). Try running the motor without the S/C running and then from there check your flywheel. Is it just misfiring? After I fouled a set of plugs on the stock motor, it was ROUGH. Try everything you can externally before you go the expensive route.
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From: NYC metro area
Originally Posted by dhdenney
Well I would try everything in simplest order. I just have thought that the stock driveshafts on these cars are bad to be out of balance but you said it does it in neutral too so that rules that out but something to look at anyway (for later). Try running the motor without the S/C running and then from there check your flywheel. Is it just misfiring? After I fouled a set of plugs on the stock motor, it was ROUGH. Try everything you can externally before you go the expensive route.
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Originally Posted by dhdenney
No prob. Have you done a cam swap in an F body? I'm wanting to but I don't wanna fool with it. Did you do it without removing the front bumper cover?
About the plugs, my car was running pig rich for a while. You think this could have killed the plugs? Would bad plugs cause the vibration?
Well mine was running really rich as well. I don't know if a rich condition would necessarily foul a plug. I'm not an expert though so I wouldn't know about that. I've never heard of it though. When I fouled that one set, I was running nitrous without a timing retard and it eat 'em up. However a carbon buildup on a plug would eventually just burn off right?
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From: NYC metro area
Originally Posted by dhdenney
Well mine was running really rich as well. I don't know if a rich condition would necessarily foul a plug. I'm not an expert though so I wouldn't know about that. I've never heard of it though. When I fouled that one set, I was running nitrous without a timing retard and it eat 'em up. However a carbon buildup on a plug would eventually just burn off right?
Originally Posted by dhdenney
No prob. Have you done a cam swap in an F body? I'm wanting to but I don't wanna fool with it. Did you do it without removing the front bumper cover?
Yes you can can swap without removing the front bumper cover. Generally (not in this exact order necessarily) you pull your fans, then radiator, plastic air dam (front of radiator), hoses, etc etc, this will also give you some room for pulling the balancer, waterpump, opti, timing cover, etc. When your finally ready to pull the cam out using (3) 7/16" thread x 4" long bolts screwed into the front of cam as a handle you ease it out carefully (don't want to scar your cam bearings), about halfway out remove the (3) bolts and continue, the cam will slide all the way out with about a 1/4" of space remaning prior hitting a sheetmetal support frame, just angle it once free from the engine and prepare for your new cam.
Thanks bud. Someone had already given me a good LS1 cam swap link but it's the same thing really. Glad you give me the measurements on those bolts though. I could go ahead and have those instead of figuring it out when I got to the cam.
