Rattle under the valve cover

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Otateral

Otateral

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I have a 69 valiant. 225 automatic. It's had a rattle while in drive (only at low speeds) and had figured it was the grille or something rattling. Today, had a helper push the brake in gear and I got out to listen. It's definitely coming from under the valve cover.

I know I won't know what it is until I remove the cover. Plan on doing that and uploading some pics. Has anyone come across this? It's not a heavy knocking, just a rattle sound but it is fairly loud. Easily heard from inside the car with the windows up. Doesn't happen in neutral and giving it some gas gets rid of it.
 
sure its not just the /6 sound? if its not it could be spark knock from a vaccum canister on the distributor going bad or a bad batch of gas
 
Some years have a valve adjustment , i think it was 10 thou on the intake and 20 on the exhaust , will quiet it right down i did it one time on a 79 volare i had , big difference.
 
sounds like the torque converter is hitting the metal dust shield on the transmission to me; familiar sound. have you had the starter off in the last little bit?

its a simple fix and doesnt require any hard work
 
Otateral said:
I haven't had the starter off. But simple fix sounds like just what I need :)

How do I go about it?
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put the car up on ramps and block the rear tires; start it and put your ear next to the front of the transmission and see if its louder there then by the valve cover
 
Get some tubing, stick one end in your ear, the other at various spots on engine & transmission to better pinpoint that sound. Just pop off valve cover, and look, it would take less than five minutes, and if problem is not found, move on to tin inspection / dust cover at front of transmission.

If you find the sound coming from dust cover area, pull starter motor, rotate engine by hand with fan, and tighten up any of the four loose converter bolts... Have some blue Loctite, and brake cleaner on hand to clean threads so Loctite will stick.
 
wjajr said:
Get some tubing, stick one end in your ear, the other at various spots on engine & transmission to better pinpoint that sound. Just pop off valve cover, and look, it would take less than five minutes, and if problem is not found, move on to tin inspection / dust cover at front of transmission.

If you find the sound coming from dust cover area, pull starter motor, rotate engine by hand with fan, and tighten up any of the four loose converter bolts... Have some blue Loctite, and brake cleaner on hand to clean threads so Loctite will stick.
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I'm highly doubtful that the torque bolts are coming loose if it hasen't been apart; more likely the inspection/dust cover got bent by a rock or something of that sort
 
it sounds like a souhnd im coming from but only does it when cold at idle like stops or lights i think its the heat riser sounds like pinto beans in a soda can jumping around
 
Alright, I got down under the car and it seems to be louder near the transmission, but it's really hard to tell. I pulled the valve cover and took some pics, not sure if they will help. Some of the (rockers? Really not good with terminology) can wiggle side to side if I grab them, but not all.

The PCV Valve is new, but I re-used the same gasket. Really don't think that's it. It sounds like a screw sitting on a vibrating plate, if that makes sense. So, a loose screw or a plate tapping against another piece of metal makes the most sense to me.
 

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63VALIANT*KISS said:
it sounds like a souhnd im coming from but only does it when cold at idle like stops or lights i think its the heat riser sounds like pinto beans in a soda can jumping around
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It does it cold or hot, but only when in idle while in gear. It seems once the engine gets over a 800-1000 rpms the rattle goes away. Don't have a tach, so just an estimate on the rpms.
 
Sounds like it might be time for a valve adjustment. Read up by searching around here on how to do it. Have you been hot rodding it? If you over revved it you may have bent a pushrod. tmm
 
Not really. Took it up to 90mph once about 3 months ago, but that's it. I found a post by slantsixdan about valve adjustments that looks pretty thorough. Possibly more advanced than what I'm capable of, though.
 
Otateral said:
Not really. Took it up to 90mph once about 3 months ago, but that's it. I found a post by slantsixdan about valve adjustments that looks pretty thorough. Possibly more advanced than what I'm capable of, though.
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it really points to that tin dust cover on the transmission

does it sound like this but quieter? [ame="https://www.youtube.com/watch?v=QQ-8nCEV1uo"]Flex plate bolts hitting inspection cover - YouTube[/ame]
 
toolmanmike said:
Sounds like it might be time for a valve adjustment. Read up by searching around here on how to do it. Have you been hot rodding it? If you over revved it you may have bent a pushrod. tmm
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Sorry for the misdiagnosis. I just watched (and listened) to the video. I'll bet you guys are right with the converter shield noise. While you have the valve cover off you might as well adjust the valves. Slantsixdan's instructions will show you how. He's a smart guy and a great teacher. tmm
 
Mine sounded more like a tick, yours sounds more like a jingle. Could be the TC cover is loose? Either way, it's probably the TC cover.....
 
Crawl under car; look at the front facing tin cover on lower bell housing of transmission. It is half-moon shaped, and will require several bolts be backed off, and or removed to take it off. This can be one of those PIA projects depending on how your exhaust is routed, and how greasy that area is.

Using the ear to hose method of chasing mechanical noise previously described will pin point your mystery sound. The tubing I use doubles as a syphon hose…
 
Well, taking things 1 thing at a time I adjusted the valves (boy that was fun! Still got oil in my hair) and put a new gasket on. And strangely... I haven't noticed the rattling sound anymore. Will have to drive it a bit more to see if it's gone for good, but we'll see how it goes.
 
Well, taking things 1 thing at a time I adjusted the valves
(boy that was fun! Still got oil in my hair)
I haven't noticed the rattling sound anymore.
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Don’t you mean oil in your ears?


Second thought:
Rather than 10W30 I recommend Brylcreem for that greasy kid’s look so popular in the first half of twentieth century before the Beatles hit these shores.

Hope you fixed the problem.
 
wjajr said:
[/FONT]


Don’t you mean oil in your ears?


Second thought:
Rather than 10W30 I recommend Brylcreem for that greasy kid’s look so popular in the first half of twentieth century before the Beatles hit these shores.

Hope you fixed the problem.
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I was more of a Vitalis guy...now I have no hair...not sure if the 2 are related...
 
I was more of a Vitalis guy...now I have no hair...not sure if the 2 are related...
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Me too, I was never a “little dab will do yeah” guy as well. I never liked using white axel grease from a tube on my head.

Rest assured that Vitalis is not chemical hair remover, even back it the day repeat customers were king, and for proof, I have 90% productive cranium follicles adorning the old dome. Unfortunately your lack of the flexible head protein strands gene is to blame for your shining example.
 
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