New motor whining noise - The 1947 - Present Chevrolet & GMC Truck Message Board Network

fdbdw · 03-27-2020, 04:47 PM

New 454, whining noise that increases with RPMs when cold then goes away after warm up. Hard to pin point with naked ear, threw on a stethoscope and my best guess is that it’s coming from the distributor ( but not positive). Anyone have any thoughts or experiences with this?

**Steeveedee** · 03-27-2020, 05:14 PM

Can you make a recording and play it back for us?

fdbdw · 03-27-2020, 05:19 PM

Quote:

Originally Posted by Steeveedee

Can you make a recording and play it back for us?

I can, I’ll have to let it sit overnight and get cold. Definitely a a whine and not a vacuum whistle. Best way I can describe it is, sounds like a blower whine.

mikeshome · 03-27-2020, 06:42 PM

Maybe try removing belts and start,eliminate everything at the front first,

fdbdw · 03-27-2020, 07:54 PM

Stethoscope points me to the rear of the motor. Pulled distributor, gears look fine. I would be more worried about the gears not aligned but it goes away once warm. Working 24 hour shift tomorrow, be back at it Sunday.

**Steeveedee** · 03-27-2020, 08:24 PM

Are you using a solid steel cam gear?

fdbdw · 04-01-2020, 08:34 AM

Quote:

Originally Posted by Steeveedee

Are you using a solid steel cam gear?

Yes, melonized steel gear

fdbdw · 04-01-2020, 08:38 AM

Update, gears on the dizzy don’t show any wear or markings. Got to thinking about it last night. Wonder if it’s the torque converter leading me to the back of the motor , freshly rebuilt th400. Another long shift today, gonna investigate that tomorrow

jbarron · 04-01-2020, 09:41 AM

I had a motor doing this. Micro imperfections in the cam finish. Go search youtube for cam whine.

JMac11 · 04-01-2020, 10:02 AM

Have seen BBC with High Volume Pumps pull the cam back towards the distributor causing wear between timing gear and block. Rare but drastic, check oil for metal or with distributor out check back and forth travel on cam.

GASoline71 · 04-01-2020, 10:04 AM

Starter bendix not retracting fully and starter gear teeth barely touching flexplate?

Gary

**Steeveedee** · 04-01-2020, 11:32 AM

Quote:

Originally Posted by fdbdw

Yes, melonized steel gear

This can sometimes cause a whine. Though you have found it louder in the back.

garyd1961 · 04-01-2020, 11:47 AM

Power steering pump?

my67c20 · 04-01-2020, 02:58 PM

Back of the engine, like near the passenger seat? If so experience tells me that is not going to go away for a loooooooong time.

weq92f · 04-01-2020, 03:29 PM

Quote:

Originally Posted by my67c20

Back of the engine, like near the passenger seat? If so experience tells me that is not going to go away for a loooooooong time.

LOL.

I'm thinking dizzy related. Use some marking compound on the gear, assemble and rotate then check it.

-klb

fdbdw · 04-01-2020, 03:35 PM

Quote:

Originally Posted by my67c20

Back of the engine, like near the passenger seat? If so experience tells me that is not going to go away for a loooooooong time.

Nailed it, sometimes I overlook the obvious

JMD · 04-01-2020, 08:13 PM

Newly rebuild TH400? Any performance upgrades in the tranny? I'd bet your transmission is starving for fluid, change the filter to a high flow/performance. I had the same issue with my newly rebuilt 454 TH400 combo. Changed the filter and it was good as new.

Edit* My issue sounded exactly like blower whine, changed with RPM as well as gear shifts, and went away as soon as the transmission warmed up.

**clay68c10** · 04-02-2020, 09:53 AM

Quote:

Originally Posted by JMD

Newly rebuild TH400? Any performance upgrades in the tranny? I'd bet your transmission is starving for fluid, change the filter to a high flow/performance. I had the same issue with my newly rebuilt 454 TH400 combo. Changed the filter and it was good as new.

Edit* My issue sounded exactly like blower whine, changed with RPM as well as gear shifts, and went away as soon as the transmission warmed up.

I've had the same noise as well. Use the bronze mesh style filter, it will take care of it if that is the source.

fdbdw · 04-27-2020, 05:14 PM

Just wanted to update.
Turns out it was the torque converter from my TH350 I re-used in the TH400.
Had some fine flakes in the fluid . Replaced converter, fluid & filter , tranny all cleaned up
All good now, I appreciate all the input.

**Steeveedee** · 04-27-2020, 05:53 PM

Good to see that it's fixed, and thanks for letting us know!

03-27-2020, 04:47 PM	#1
fdbdw Registered User Join Date: Jan 2009 Location: colorado springs Posts: 479	New motor whining noise New 454, whining noise that increases with RPMs when cold then goes away after warm up. Hard to pin point with naked ear, threw on a stethoscope and my best guess is that it’s coming from the distributor ( but not positive). Anyone have any thoughts or experiences with this?

03-27-2020, 05:14 PM	#2
Steeveedee Who Changed This? Join Date: Jan 2013 Location: Simi Valley, CA Posts: 10,724	Re: New motor whining noise Can you make a recording and play it back for us? __________________ ~Steven '70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper Simi Valley, CA

03-27-2020, 06:42 PM	#4
mikeshome Registered User Join Date: Jul 2013 Location: Mount Albert.Ontario Posts: 119	Re: New motor whining noise Maybe try removing belts and start,eliminate everything at the front first,

03-27-2020, 07:54 PM	#5
fdbdw Registered User Join Date: Jan 2009 Location: colorado springs Posts: 479	Re: New motor whining noise Stethoscope points me to the rear of the motor. Pulled distributor, gears look fine. I would be more worried about the gears not aligned but it goes away once warm. Working 24 hour shift tomorrow, be back at it Sunday. Last edited by fdbdw; 03-27-2020 at 07:55 PM. Reason: Grammer

03-27-2020, 08:24 PM	#6
Steeveedee Who Changed This? Join Date: Jan 2013 Location: Simi Valley, CA Posts: 10,724	Re: New motor whining noise Are you using a solid steel cam gear? __________________ ~Steven '70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper Simi Valley, CA

04-01-2020, 08:38 AM	#8
fdbdw Registered User Join Date: Jan 2009 Location: colorado springs Posts: 479	Re: New motor whining noise Update, gears on the dizzy don’t show any wear or markings. Got to thinking about it last night. Wonder if it’s the torque converter leading me to the back of the motor , freshly rebuilt th400. Another long shift today, gonna investigate that tomorrow

04-01-2020, 09:41 AM	#9
jbarron Registered User Join Date: Apr 2006 Location: Spring, Texas Posts: 167	Re: New motor whining noise I had a motor doing this. Micro imperfections in the cam finish. Go search youtube for cam whine. __________________ '72 3/4 Cheyenne Super 402/TH400 Gear Vendors '72 3/4 Cheyenne Super 350/200R4 '50 1/2 Chevy 3 Window

04-01-2020, 10:02 AM	#10
JMac11 Registered User Join Date: May 2005 Location: Tallahassee Fl Posts: 773	Re: New motor whining noise Have seen BBC with High Volume Pumps pull the cam back towards the distributor causing wear between timing gear and block. Rare but drastic, check oil for metal or with distributor out check back and forth travel on cam.

04-01-2020, 11:47 AM	#13
garyd1961 Registered User Join Date: May 2016 Location: Henderson NC Posts: 975	Re: New motor whining noise Power steering pump?

04-01-2020, 02:58 PM	#14
my67c20 Registered User Join Date: Jun 2002 Location: Tucson AZ by way of WI & CA Posts: 510	Re: New motor whining noise Back of the engine, like near the passenger seat? If so experience tells me that is not going to go away for a loooooooong time.

04-01-2020, 08:13 PM	#17
JMD Registered User Join Date: Jun 2013 Location: Grand Rapids Michigan Posts: 291	Re: New motor whining noise Newly rebuild TH400? Any performance upgrades in the tranny? I'd bet your transmission is starving for fluid, change the filter to a high flow/performance. I had the same issue with my newly rebuilt 454 TH400 combo. Changed the filter and it was good as new. Edit* My issue sounded exactly like blower whine, changed with RPM as well as gear shifts, and went away as soon as the transmission warmed up. __________________ My build thread: http://67-72chevytrucks.com/vboard/s...96#post7439296

04-27-2020, 05:14 PM	#19
fdbdw Registered User Join Date: Jan 2009 Location: colorado springs Posts: 479	Re: New motor whining noise Just wanted to update. Turns out it was the torque converter from my TH350 I re-used in the TH400. Had some fine flakes in the fluid . Replaced converter, fluid & filter , tranny all cleaned up All good now, I appreciate all the input.

04-27-2020, 05:53 PM	#20
Steeveedee Who Changed This? Join Date: Jan 2013 Location: Simi Valley, CA Posts: 10,724	Re: New motor whining noise Good to see that it's fixed, and thanks for letting us know! __________________ ~Steven '70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper Simi Valley, CA



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