Lend me you ears

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Edit: your*

Just finished the first valve adjust on the new to me 64 dart with a 225.

Before I did the adjustment the engine was nearly silent when running with a slight tick when hot.

I warmed up the engine by driving it around and getting it to operating temperature. Remove valve cover and set to doing the valves by turning the engine over with a starter switch and aligning it to the marks that I've made on the balancer. Marks were made by dividing the balancer circumference and measuring.

Now the engine is considerably louder and sounds like a sewing machine. Not clacky just tappy. It doesn't sound bad and drives great it's just much noisier than what it was.

When I was doing the valves they were set extremely tight under .010 on all valves. Previous owner said that the engine had a top end done within the last few years, everything under the valve cover looks clean and new.

video is taken with the engine at operating temperature.

 
Better loose then too tight, it does take practice & patient adjusting valves. You could use the go / no go method, using two feeler gauges correct size and then using a size larger for a no-go. They do make feeler gauges for this purpose....

gauges.jpg
 
Yep I used to go no-go gauges, I have that exact set. And i verified with a standard set

And for some background I've been doing valve adjustments on many many other vehicles for 20 years. Primarily Land Rover diesels, airhead BMW motorcycles, and other early European cars.

First slant.

what really threw me off is how absolutely silent the car was when running prior to doing this. and that the valves were adjusted so tight I couldn't even fit the feeler gauge underneath of it before I did the adjustment.

This seems right it's just so much noisier than what it was! I do appreciate the insight
 
Yup that's how they sound, always set it hot, just stick a shirt on the side to catch oil. Stock I like setting it on the loose side,012 and .022 little loose.
 
Sounds good to me! I think you did a great job; not a ticker in the bunch.i
I go 13/23 at 65/75*F ambient.
Take it for a ride, I bet it squeals the tires now,lol.
But you gotta be careful. Every slanty I ever worked on, which ain't that many,lol; the rocker arms were rutted, and I had to use narrow gauges to get into the ruts. I just cut my regular feelers up the middle for about 3/4 inch.
 
Here's my theory. As engines run, they wear. As valves and seats wear, the valve stem height increases, because the valves are slowly sinking into the seats. This reduces the valve lash over time, especially if normal valve adjustments are neglected.

So my theory is no one went through anything. It just needed a valve adjustment from years of neglect.

Of course, I could be entirely wrong. Someone might have adjusted them all too tight, but which sounds more likely?
 
Oh and I never adjust any engine's valves hot, I don't give a flubmuffin what the book says. No sense in takin a chance on gettin burned. Engine temperature just doesn't make enough difference in valve lash to matter with how the engine performs.
 
We took it for a 100mile ride down the pch to pebble beach, it's running great . It's quieted down a bit and power is better.
 
We took it for a 100mile ride down the pch to pebble beach, it's running great . It's quieted down a bit and power is better.

That's because as it warms up, the valve train expands a little and closes the lash up a tad. Glad you got it goin good.
 
I'm probably going to catch some flak for this, but your valves sound like they need adjusting. The are noisy.

I've always adjusted mine [on different cars] using this method:
Run the engine till it is hot.
Drop idle speed.
Remove valve cover.
Mark all the intake valve retainers with bright paint.
Start engine.
Adjust the intakes --- .010 feeler slides easy --.012 doesn't ----Use a 3/8 x 7/16 12 point double box wrench [sears works well]. Point the wrench to the front of the car.
Adjust the exhaust --- .020 feeler slides easy -- .022 doesn't
Recheck the adjustment.
Valve cover on. Reset the idle speed, Road test.
 
Repeat the process,engine cold to same specs. As it warms up the lash will tighten up and it should be a tad quieter.
 
Oh and I never adjust any engine's valves hot, I don't give a flubmuffin what the book says. No sense in takin a chance on gettin burned. Engine temperature just doesn't make enough difference in valve lash to matter with how the engine performs.

Makes about .006 on aluminum headed engine -------------
 
It is best to set the valve lash hot and running. Cam lobes are not symetrical and if you do some checking you will find that the static adjustment is not the most accurate.
 
In my experience, my solid lifter slantys all liked to be a bit ticky; when they get quiet, bad things happen. Yours sound just right.
Even a couple of thou too tight on the intakes will affect the idle. None of mine have liked the .010 intake/hot spec. Mine would idle there but it took extra throttle to get the same idle-speed, and then the blades were up too far on the transfers. Then it gets hard to get the carb right. Then when I make her work hard and the head gets warmer, it all takes a dump. And since it gave me no more power, nor less, seat of the pants; I settled on 13/23 at about 70*F. And then it goes all year without adjustment, sometimes several years.
My last slanty car has become my emergency back-up car. I've had her since 1994. but she hasn't been registered now for at least 4 years. Engine still runs great, but her body is returning to her native state. I warm her up, and move her around the yard whenever the mood strikes me. But the front tires don't hold air anymore, so it's getting moved less and less every year. But it runs and drives too good to be scrap........
 
That's how mine sounds. Like a sewing machine idling at 500 rpms.

This after a complete rebuild. My machinist refaced the rocker arms because they were grooved after 97,000 miles so I'm pretty confident I was getting true readings. I would assume the rocker faces were originally hardened so not sure how that will work out long term. 8000 miles on new engine. I should probably pull the rockers in the spring and see how they're holding up.
 
Sounds like every slant six I have messed with...except for the last one...it wiped out a rod bearing....it sounded a little different...lol
 
As you already know because you asked on the Slant-6 board and got this same answer: Yes, it's normal to be able to hear 'em…a little. They should not be as clearly audible (loud) as they are in your video.

Try using this valve adjustment procedure (the whole procedure, including having the engine running) and see if you get a better result.
 
Anyone have a video with excellent audio quality that can give me an idea.

Lots of conflicting info

My cam takes excellent video and audio, I'd love something similar
 
Hearing someone else's slant-6 engine won't help you as much as you'd like—they vary more than common sense might suggest, depending on explainable stuff like different camshafts (factory cams not all alike), amounts of wear, grades of oil, skill and talent of whoever last adjusted the valves (and how long ago), and how hot the engine is…

…and unexplainable stuff along the lines of why some of these cars have rock-steady charging no matter how much neglect they've seen, and other cars, seemingly identical, have flickery charging even after every component, wire, connection, and ground in the whole system has been gone through with a fine-tooth comb.

All that said, the main reason why the Slant-6 has a reputation for "Aw, that's normal, they all go clackity-clackity-clack" is because most of them don't get the valves adjusted as often or as carefully as should be. Your valves, to my ear, are loud enough to warrant readjustment. Whether you readjust them is up to you.
 
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Oh and I never adjust any engine's valves hot, I don't give a flubmuffin what the book says. No sense in takin a chance on gettin burned. Engine temperature just doesn't make enough difference in valve lash to matter with how the engine performs.

"flubmuffin" ? where u from? Maycon Ga? that must be one them "southern whitisizems :)
 
Anyone have a video with excellent audio quality that can give me an idea.

Lots of conflicting info

My cam takes excellent video and audio, I'd love something similar

Take Dan's advice. He's the go to guy for all things slant six. And lighting too. I have terrible high frequency hearing loss, so I am sure I am not hearing all of the noise Dan is.
 
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