Could I get some opinions on this timing belt noise?
#1
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Could I get some opinions on this timing belt noise?
Replaced all rollers, water pump, timing belt (of course) and installed a cam timing advance key. No balance shafts as you can see in the video. I set the tension using the latest Arnnworx tool, and didn't have any issues with it - tension seems reasonable.
Does this match any tell-tale culprits, to you very experienced 944 wrenchers? It sounds like a bearing to me but am curious to hear what others think. It sounds like a supercharger whine (almost... a little quieter and more ghetto sounding) starting just under 3k RPM. Under the hood, it was much more pronounced, and after shooting this video I threw it into the garage and killed it,
#3
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Tension is set to 0, doesn't exist on this car
Which is why I'm worried. If I had a balance shaft setup and it made this noise, I wouldn't think anything of it because that's fairly normal.
Which is why I'm worried. If I had a balance shaft setup and it made this noise, I wouldn't think anything of it because that's fairly normal.
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#9
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Re: ignition
They're LS1 coils running in wasted spark, via a MegaSquirt (Microsquirt to be specific). In the video, you can sort of see the crank trigger and the AFM delete setup w/ GM IAT sensor haha.
#10
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Ok, now I'm second guessing myself on the belt tension. I set it using the Arnnworx tool, and I'm unable to spin the water pump by hand. That seems to be the other "rule of thumb" test passed around in addition to the 90* twist method. I've done belts before and usually I can spin it by hand.
WP is new and is not seized...it spins freely with less tension on the belt. Maybe the belt just has more grip on the water pump due to its material, and I'm worrying about nothing? I'm only concerned because of the whining noises earlier, but every other method of determining a good tension in checked off.
WP is new and is not seized...it spins freely with less tension on the belt. Maybe the belt just has more grip on the water pump due to its material, and I'm worrying about nothing? I'm only concerned because of the whining noises earlier, but every other method of determining a good tension in checked off.
#13
Mike, my car also whined like that also after I replaced the belts and rollers. I used the ArnnWorx 920x also. After a 100 mile drive the whine was about half of what it was. After 500 miles there's almost no whine when hot. I used Continental's belt and roller kit. I hope this makes you feel better.
#15
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Thanks Marc, I'll keep that in mind.
AZ250, I don't believe this to be the case. I painted the belt guard for this reason (to tell me if there was contact under any circumstances) and there is no scuffing. With the engine off, there is at least 1/8" gap, and the idler doesn't push the belt span closer.
AZ250, I don't believe this to be the case. I painted the belt guard for this reason (to tell me if there was contact under any circumstances) and there is no scuffing. With the engine off, there is at least 1/8" gap, and the idler doesn't push the belt span closer.