Hi, running a 225 from 1977 in a dodge van and I got this rattling noise coming out of the engine, like something is loose and hitting something inside the engine. The rod and crank bearings are fine, valve lash have been adjusted and the timing chain is OK.

I checked the timing chain today and it's fine and the converter, to check if there were any loose bolts. Could to much advance in the ignition system cause this?

This sound is new to me, and hope you guys have a clue what it might be!

Engine or rather odd noise is hard to diagnose without hearing it in person, so be patient with us on this one.

Is the noise a deep heavy solid thunk or clunk and rhythmic?

Is the noise lighter sound from say a less massive chunk of metal that could have loosened just enough clatter?

Is it tinny such as an air cleaner snorkel rattling against a solid object as the engine moves about on its mounts?

Dose this noise only manifest when sitting in gear idling at a light, and when a load is placed on drive train dose it go away?

Try to describe the sound in more detail, and where it appears to be coming from for us.

Things to look at, or rather, listen to: air cleaner and related parts hitting on something; loose flex plate bolts, something internal hitting oil pan; engine mounts; transmission mounts; fan, brake backing plates; exhaust parts too close to undercarriage; etc.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

You might pull dipstick out, some of the others have had their dipsticks broken off. The dipstick should have a slight curve towards the outside of the pan.

Richard

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Part of Tyrde-Browne Racing

The sound occurs at idle, mid-throttle, but seems to fade away when I rev it up. It sounds like hard metal to metal noise, but the sound level and rhytm remains the same at any rpm.

Thanks

Might be an exhaust leak. Look for a crack in the exhaust manifold and feels for exhaust leaks around the head and the exhaust manifold to pipe junction.

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Casually looking for a Clifford hyperpak intake for cheap.

Exhaust pipe is a possibility. Check to make sure it isn't touching something under the car. It can transmit up the head pipe and sound like it's coming from the engine.
It can start at the back of the car, but generally sounds like it's back there if thats the case.

CJ

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Part of Tyrde-Browne Racing

The exhaust manifold haven't cracked as far as I know, and the exhaust pipe is sealed with new gaskets. Going to record the sound for you guys, but for me it seems like the fan is either hitting the trans. cooler liner or there is something laying on the rockers.

PCV Valve Rattling?

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1965 Dart 110k, 225, Carter BBD Super Six, 2 1/4 single exh., sbp manual scarebird front disc, 7 1/4 rear 2.94 sure grip, 14 x 4.5 OEM wheels, 833 OD with hyd. throwout bearing, HEI, electric fan, ram air/heated air, Accusump. http://plymouthcarclub.com/

How loud does is the rattle from the PVC valve?

Just palpate the valve with your fingers, you may feel a slight vibration as its plunger osculates up & down, and determine if that matches your noise. I’m betting that it won’t be the source of your noise, as the sound from a PCV valve is more of a buzz if it can be heard at all.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

If this is an auto, your description sounds a lot like loose torque converter bolts.... Or a cracked flexplate.

Even heard vaguely similar noises just from loose bellhousing to engine bolts.

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'81 W150 on Propane... Oversize valves, Oregon Camshaft cam, 10:5 static CR, Distributorless ignition, megajolt timing controller, PowerTrax lockers.