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| | | Forums66 Topics128,162 Posts1,056,943 Members48,458 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jul 2009 Posts: 90 Shop Shark | | Shop Shark Joined: Jul 2009 Posts: 90 | I am assuming that car engines are acceptable here? When I rebuilt my 235 (from a '57 Chevrolet)I used the aluminum timing gears rather than the stock type cork, or whatever material that stuff is. Has anyone done this and then they had a noise? It seems as those these gears are somewhat loud. Not like a constant grinding. I don't want it to be confused with a rod knock, but it does have a "knock" type noise.
thanks, brandon | | | | | Joined: Sep 2006 Posts: 2,393 Shop Shark | | Shop Shark Joined: Sep 2006 Posts: 2,393 | The aluminum gear is sturdier but noisier. You should have replaced the crank gear with it. If not,this also may account for the added noise.
Drew
| | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | Whatever is, a Phenolic (Bakelite) gear. And yep, the reason they used them was because they are quieter; the alum to steel combo is noisy. The noise you should be hearing is a whine, if your hearing a clunk it's probably something else. I don’t see how your crank gear could be worn enough to cause a clunk, if it was I’m afraid your engine would be running a little rough also. It's very difficult to put an engine sound down on paper; it’s the same as trying to describe how Bruce Springsteen’s guitar sounds. Here's a bit I wrote on the subject for a discussion on another forum: “Is there really any way possible to communicate, convey, describe, transmit or just plane get across in print what the sound of "piston slap" would sound like, or "rod knock", or "main bearing clunk". Tappet clatter is pretty easy for most people to describe or to recognize from a description, but I think the other engine sounds in many cases are misinterpreted. Now next to “How to Hand Form Your Own Fenders” this would probably be one of the biggest selling CD's of all time for the old car enthusiast, just think, "Those Ominous Engine Sounds in Stereo", different tracks for a four, six or eight. Start them all off cold with that crankshaft thump or is that a clunk or thud, and then run them up to a nice warm engine ping. So all we need is a combination master mechanic/ sound engineer with the entrepreneurial spirit to pick up on this.” Denny (Click & Clack) Graham Sandwich, IL
Denny G Sandwich, IL
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | If you go to the trouble to check run-out when installing a aluminum gear and make sure it is within spec., it will be almost silent.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Dec 2003 Posts: 2,733 Shop Shark | | Shop Shark Joined: Dec 2003 Posts: 2,733 | Mine was properly installed and fitted an has no perceptable noise, at least to my old ears and that's all that counts to me. On the other hand maybe I just got lucky. | | | | | Joined: Jul 2009 Posts: 90 Shop Shark | | Shop Shark Joined: Jul 2009 Posts: 90 | I knew absolutely nothing of engines when I started this rebuild. I had several older fellows helping me. Unfortunately, they had much of it assembled before I showed up on time, and then there were so many working at once, I was unable to truly learn a lot. I replaced both gears. Since then, I have had the engine completely rebuilt (again) by a reputable machine shop (i kept having troubles). This engine has given me a fit. I actually just wanted someone to help me rebuild it so I could learn to do it myself and from then on when I did work, I would know it's right.. but unfortunately finding people that actually know how to work on these engines is more difficult than it seems. Obviously, not in a forum about them, but locally, in the real world, I just don't have the connections. You're right, I can't really describe the noise. Maybe I can make a youtube video eventually that will capture the noise. I also, even after the rebuild, have an oil leak on the flywheel that causes the car to shudder violently on most take offs (i've learned to work around it with the right clutch slip), but that's another problem for another day.... one at a time... | | | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | sorry I cannot help with the cam gear issue.
I just wanted to add a little on the clutch shudder.
Clutch lining is like brake lining, in that, ANY amount of contamination on either surface is going to cause an issue.
I'm not talking about the obvious oil leak , but more the original installation technique.
Don't even put your fingers on the lining.
We all have different levels of body oil and acid in the pores of our skin , if you know what yours is like , then fine. Otherwise play it safe , don't touch the linings.
ps, rear main oil seal leak doesn't normally affect the clutch, it can look bad running down the flywheel , but with the engine running , the oil is thrown off onto the bellhousing.
It does sound like the rear main seal was installed incorrectly , but there may well be another issue to explain the clutch problem. eg, dirty/greasy fingers on the lining , or pilot bearing grease flung onto the lining , or excessive spline lube also flung out onto the lining .
Clutch shudder is also affected by soft engine mounts or bad flywheel/pressure plate run out. | | | | | Joined: Jul 2009 Posts: 90 Shop Shark | | Shop Shark Joined: Jul 2009 Posts: 90 | I don't really know how to start testing for that without just replacing things. It's probably something that can't be diagnosed on the internet. The clutch pedal first wanted to fall to the floor after it was pushed about 2 inches. I put an extra spring under the hood on the clutch rod. I have to adjust the clutch pretty far up, so it's difficult to take off without getting used to it. It shudders in 1st (and reverse) and oil leaks from out of the dust cover pan. I've had the flywheel turned more than once. When I get some other projects done (like fixing the stupid leaking front and rear windows that the window shop was SUPPOSED to fix when it pulled and reinstalled the window), then I'll eventually get to that mess.
After thinking about the conversation here I listed again to the noises coming from the gears, or what I believe to be the gears. It's more of a chatter than a knock. A metal chatter. It's not constant... it kind of rattles for 3 or 4 rattles, then stops... then does a shorter one, then stops, then back, and repeats this... the whole short/long cycle being about 4 or 5 seconds. | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | When I first put mine together, I had a random squeaking/chirping that was worst around idle. I used a piece of tubing to listen to it and it turned out to be the harmonic balancer (crankshaft pulley). It eventually went away. | | | | | Joined: Feb 2004 Posts: 29,859 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,859 | I'm about 30 miles from you, and I've been listening to engine noises for 50+ years. Drop by my shop sometime, and I'll try to help out. I'm the auto mechanics instructor at McGavock High School in Donelson. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | Now that's even better than that CD I was talking about Brandon. Hey Jerry, ever think of making a, "Those Ominous Engine Sounds in Stereo" CD as a school project???? Denny Graham Sandwich, IL
Denny G Sandwich, IL
| | | | | Joined: Feb 2004 Posts: 29,859 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,859 | Hmmmmm- - - - -interesting idea! I once diagnosed a rod knock from 80 miles away by having my wife hold the telephone close to her engine. That one was a no-brainer, though! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Dec 2008 Posts: 1,922 'Bolter | | 'Bolter Joined: Dec 2008 Posts: 1,922 | The noise you should be hearing is a whine
I wonder if there's enough room inside the cover for some sound-deadening material to be sprayed on (bed liner) or glued on (Dyna-Mat)? | | | | | Joined: Jul 2009 Posts: 90 Shop Shark | | Shop Shark Joined: Jul 2009 Posts: 90 | Thanks for the offer. I'll definitely take you up on that sometime. I appreciate it.
I have the floorboard covered in dynamat, by the way. The engine noise (and road noise) is still super loud. Not the bad engine noise, just normal engine noise.
Last edited by Vetteman61; 01/23/2010 8:44 AM.
| | | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | Jerrys' offer is definately the best thing going here  OK, So isn't it great the way a thread grows. I have an issue with the addition of sound proofing , particularly on a near standard old chevy truck . Different if you've added a diesel ............. Thing is , to me , the old girl is normally pretty quiet , and needs to be listened to , she has a lot to say about how the driver is treating things. You go cover those whispers up , and communication is lost. But if the noise is so loud you can't think .. then you have issues that need addressing, NOW. Before the old girl goes BLAM! Well , what the heck , I guess it depends on how much $$$ you have to spend on repairs, eh. | | |
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