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#1 |
Active Member
Join Date: Jan 2006
Location: Lower Mid-East Ca.
Posts: 326
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Engine ? noise
I'm getting a noise I think is from the engine that is making me scratch my head, hoping somebody might have some ideas to try other than a teardown...
Here's the rundown; 350 4spd, I had 3.08 rear gears and at highway speed ran about 1900 RPM. Put 4.10 gears in it and now run close to 3000 RPM down the road. The engine runs fine like it always has, but above 2500 RPM going down the road I'm getting a tap or rattle from the front. If I'm on or off the throttle it isn't there, but just rolling along it is. Can't get it to do it in the driveway sitting still either. The noise is heavier than a lifter, but less than maybe a rod. Doesn't do it at lower engine speeds. Oil is clean, oil pressure where it always has been, have run it up to 4000 going up throught he gears and nothing, it will rattle in 3rd gear above 2500 rpm, but not on or off throttle. Backed the timing from 12 to 8 degrees to see if it was pinging, no sign of vacuum leak either. Has me stumped.... wristpin maybe, bad input bearing in the trans? Thanks, Max
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Never try to teach a pig to sing; it wastes your time and annoys the pig! ![]() ![]() My lugnuts require more torque than your honda makes! 68 GMC, 4X4 conversion w/73 k20 running gear and springs, 350 4spd, 4.10's, D44 powerlok front, 14BFF govlock rear, 33" tires, lifted 4". |
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#2 |
Registered User
Join Date: Nov 2010
Location: Grand Terrace, Ca.
Posts: 1,607
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Re: Engine ? noise
You only hear the noise in high gear or in any gear just over 2500 rpm?
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#3 |
Redefining LowBudget
Join Date: Mar 2009
Location: lebanon Cow Hampshire
Posts: 4,538
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Re: Engine ? noise
I would check U joint back lash?? you know when its not under a load it may be slaping from push to holding back
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1970 C10 CST fleetside 472 ....big dreams little cash... SunShine Syndicate.. ![]() Mikes Sandwich Fair Run OCT 8th 2011
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#4 |
Registered User
![]() Join Date: Jan 2011
Location: Illinois
Posts: 34
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Re: Engine ? noise
If you are sure it is from the front of the engine check the timing chain and the fuel pump pushrod\fuel pump. Check fan clutch and\or blades. All sound a little heavier than a lifter but not as bad as a rod bearing. Also had a harmonic dampner make a click style noise once, the bond of the dampner was loose. Check pulleys. Just some things to check.
Bryce |
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#5 |
Active Member
Join Date: Jan 2006
Location: Lower Mid-East Ca.
Posts: 326
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Re: Engine ? noise
Randy, will do it in 3rd also,
Hott, u-joints are new, Bsteen, forgot about the pushrod/pump, have less than 20k on double roller timing set- will check balancer too, Thanks
__________________
Never try to teach a pig to sing; it wastes your time and annoys the pig! ![]() ![]() My lugnuts require more torque than your honda makes! 68 GMC, 4X4 conversion w/73 k20 running gear and springs, 350 4spd, 4.10's, D44 powerlok front, 14BFF govlock rear, 33" tires, lifted 4". |
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#6 |
Registered User
Join Date: Nov 2010
Location: Grand Terrace, Ca.
Posts: 1,607
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Re: Engine ? noise
Do you have to be going over a given mph to hear the noise?
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#7 |
Active Member
Join Date: Jan 2006
Location: Lower Mid-East Ca.
Posts: 326
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Re: Engine ? noise
No, just over 2500 rpm, driving
__________________
Never try to teach a pig to sing; it wastes your time and annoys the pig! ![]() ![]() My lugnuts require more torque than your honda makes! 68 GMC, 4X4 conversion w/73 k20 running gear and springs, 350 4spd, 4.10's, D44 powerlok front, 14BFF govlock rear, 33" tires, lifted 4". |
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