Any advice on quieting sewing machine noise?
#1
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Any advice on quieting sewing machine noise?
just bought the rx7 and attempting to familiarize myself with the domestic motors as much as possible, so these build sheets are in another language to me. the sewing machine noise is driving me crazy and i could use a little direction on how to quiet it down. thanks guys!
mods are:
build info:
mods are:
- Stock Crank
- Scat Forged Rods
- Probe Forged Flat Top Pistons
- Coated Bearings
- Ported & Polished 241 Heads by SLP
- PRC Gold Spring Kit W/ Titanium Retainers, Seats & Seals
- TSP Chromemoly 7.40” Pushrods
- TSP Custom Grind Camshaft 232/234, 595” / 598” , 114 LSA
- LS6 Intake
- Stock Throttle body and MAF
- MSD Plug Wires
- Stainless Fuel lines from engine to connectors under car
- Z06 Return Fuel Rail W/Vac FPR
build info:
#3
My engine bay was louder noticably and i ended up having two loose spark plugs haha check that. But theres alot going on under there thats alot of valve lift so its going to be somewhat noisy man. Get a stethoscope and see if its your idler pulley/ ac pulley or just your rockers
#4
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As mentioned above:
check for correct pushrod length to preload lifters, there are several part numbers which all require different preload
make sure the foam strips are still attached to the intake bottom
check rockers for damage or signs of excess wear
Depending on the cam lobes used, it might not get much quieter. Another thing is experimenting with oils. My engine was noticeably quieter with Castrol Syntec 0w-30 than Pennzoil Platinum or Mobile 1 5w-30.
check for correct pushrod length to preload lifters, there are several part numbers which all require different preload
make sure the foam strips are still attached to the intake bottom
check rockers for damage or signs of excess wear
Depending on the cam lobes used, it might not get much quieter. Another thing is experimenting with oils. My engine was noticeably quieter with Castrol Syntec 0w-30 than Pennzoil Platinum or Mobile 1 5w-30.
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ok guys. car hasn't been getting much attention. been so crazy busy at work. gonna start gettin her together. just bought a new gauge panel and speakers, but i also need to get crackin on this noise.
if it's nothing that will damage the engine i can live with it, but here's two vid's that display the noise (sorta). the dash and door panels out to get ready for the parts mention. any help would be greatly appreciated guys! thanks again.
if need be i can take our condenser mic and really get a good recording.
startup on warm day
http://youtu.be/m36vGhAOtH0
after a brisk little drive
http://youtu.be/W9uoPwcGIm8
if it's nothing that will damage the engine i can live with it, but here's two vid's that display the noise (sorta). the dash and door panels out to get ready for the parts mention. any help would be greatly appreciated guys! thanks again.
if need be i can take our condenser mic and really get a good recording.
startup on warm day
http://youtu.be/m36vGhAOtH0
after a brisk little drive
http://youtu.be/W9uoPwcGIm8
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#9
TECH Resident
TWS car Squeaky just had the Comp Cams Trunion upgrade done and the "sewing machine noise thats typical from an LSx motor went away.. His valve-train is much quieter.. However the Procharger is as "squeaky" as ever =]
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As far as my understanding goes...That sewing machine noise doesn't go away..I have it after my lts/duals went in...It's tollerable..but once my cam goes in I'm sure it will be noticably louder...I've read alot threads on this noise....Seems typical with no "for sure cure"...Unless it's a tapping or leak...It's just their to stay
#14
11 Second Club
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That particular cam has pretty aggressive lobe ramps which elevates the
common LS1 valvtrain noise. Having quality lifters and proper pushrod pre-load
along with the trunion upgrade on the rockers helps to minimize the insanity.
Also the springs need to be properly shimmed. If the duals can handle .675
lift but your cam is around .600 sometimes they can experience surge unless
they are shimmed(shorter installed height) to within .060" of coil bind.
As some have stated...the engine oil viscosity can change this sound. I went
from Mobil 1 5w30 to Mobil 1 0w40 which is a European blend and apparently
has higher zinc content(similar to high mileage oil). This slightly reduced the
noise; not by alot but noticeable.
common LS1 valvtrain noise. Having quality lifters and proper pushrod pre-load
along with the trunion upgrade on the rockers helps to minimize the insanity.
Also the springs need to be properly shimmed. If the duals can handle .675
lift but your cam is around .600 sometimes they can experience surge unless
they are shimmed(shorter installed height) to within .060" of coil bind.
As some have stated...the engine oil viscosity can change this sound. I went
from Mobil 1 5w30 to Mobil 1 0w40 which is a European blend and apparently
has higher zinc content(similar to high mileage oil). This slightly reduced the
noise; not by alot but noticeable.
#15
noise
that really doesn't sound bad at all. like noted above, it sounds like belt noise. the idler pulleys go bad on these cars. do what Lee12609 said and pull the belt and start it and see if it goes away. it seems tome that the top idler pulley goes bad more often than the bottom. i replaced mine with a manual style.
#16
how many miles on your engine ?like mentioned above remove and check your rockers for missing bearings.remove all of your push rods and measure them.maybe get some harden push rods that are .025 longer then the 1 that currently in your engine.