Hello, i´m from Spain, i have a ´73 Dodge 3700 GT and it have a strange sound like metal parts hitting.
This sound disappears when i remove the sixth cylinder spark plug wire, so i think is not from valves,i replaced valve stem seals and checked valve lash last week.
Can you help me?
This is my car (I love it!)

Thank you!

Do you have a sound bite from it? The box beneath your post didn't link to anything.

If you pull the plug wire and it goes away, likely a rod bearing. Could be big or small end, but more likely big. Small end tends to be a different sound, Is it hollow or a sharp sound?

At this stage, don't run it. Drain fluids, pull the head, and rotate the engine to look for a pause. When the piston starts to travel down the bore, stop turning the crank, and push down on the offending piston with your finger tips. If it moves at all prior to crank rotation, the bearing is gone.

CJ

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Part of Tyrde-Browne Racing

I`ll take a video for post it here.
Sorry for my english!
Im going to bed, here is 3:40 AM.
Thank you!

Beautiful car!

Now, don't start it just to let us hear a digital representation. It won't be nearly as good as standing next to it.
If you're getting a sound when running, and when you pull the plug wire for #6 wire and it goes away, you have a bearing that has gone south. (That's slang for "it's bad.")

It's time to pull the engine down and fix it.

Running it at this stage will cause further damage. Park it, and fix the problem. These engine's will take a beating, but further damage will result in more machine work. Minimize your costs by side-lining until it's in top shape!
(Side-lining is slang for "Don't run it!")

your English is just fine! Get some sleep and read this before you start the car!

CJ

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Part of Tyrde-Browne Racing

Ok, i´ll not start the engine.
Is it necessary to pull down the engine or can i replace rod bearing removing oil pan (and maybe also oil pump)?
Is always necessary to machine work the crankshaft?
Thank you!

Welcome to the site. I've heard of people replacing the bearing without machining the crankshaft but I would not do it. The engine is reeally easy to remove in these cars and you'll most likely have a better result if you do the repair correctly rather than try to take shortcuts. You would probably end up redoing it anyway if you tried to only replace the bearing and not machine the crankshaft. Good luck.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

It is easier to repair or replace engine internals with the engine out. I dont think you will be able to get the oil pan off without pulling it anyway. You may get lucky and not need any machine work on the crank (depends on how bad or long its been run) however I would at least check it while I had it apart.
Frank

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Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

Thanks for helping me!
I don´t have an equipped garage so i can´t pull down the engine ,i´ll try to find a place to do it.

Hello!
I replaced the big end rod bearing, the old one was perfect, and the engine still sounds
I want to pull off the head to replace the small end rod bearing.
Is it possible or necessary to change parts to use with unleaded fuel?
My engine's number is 2465830
Any suggestions?
Thank you!

It could be a cracked piston or a bad wrist pin going through the piston.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Saludos.

It will help for us to hear the noise, if you can record it and post a link for us to hear it.

The engine will run fine for a long time on unleaded fuel; whenever you rebuild the cylinder head, have hard exhaust valves and seats installed, but you do not need to do so before the head requires rebuilding.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Beautiful picture! Car and landscape. Welcome!

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66 Lil' Red Piggie Valiant (Mater Crusher) - Thanks Zilla!!!!! 72 Demon (Number 1 Son's)

Thank you! I'll not rebuild the head before it needs to.
The landscape is Navas del Pinar, in Spain, it's my grandmother's village.

More suggestions?
Thanks for all!

Please, tell us more about the car and the village! Thanks, Wayne.

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66 Lil' Red Piggie Valiant (Mater Crusher) - Thanks Zilla!!!!! 72 Demon (Number 1 Son's)

Do you mind if I save the picture? I collect pictures of mopars.