What's Wrong With This 225 Slant Six? Tearing Down And Diagnosing A Noisy 1973 Dart Sport Engine 

I noticed they always had a slant or poor old 318 on them

With a Demon in the background no less

Up here under the hat of canadia in good ol Montucky we have lots of ranchers and farmers. Now say what you will about how abusive we are to our vehicles but the maintenance is generally always spot on. Oil changes twice a year, full lube service whether they need it or not, and so on. I inherited my 'first car' from a distant relative who thrashed a 76 adventurer SE longbox in canary yellow/white. That old man logged 680,000 miles on that truck before I got it. 3 transmissions, countless sets of brakes and other consumables, but never had to touch that old 360 once (other than plugs, wires, ie consumables). Turns out that after that many miles and never changing the timing chain is kinda bad for when a teenager gets his hands on it. I proceeded to thrash this thing until I roached 3 holes to the point of no return. I mean 2 had dropped exhaust valves that bashed around and poked holes in the pistons. One intake valve broke off and wedged between the wall and skirt resulting in a two piece connecting rod. BUT the truck still put me down the road another 45000 miles before I got a graduation gift of a 73 charger. I retired the truck to our back field for a couple years only to be revived again down the line when the charger was out of commission and yes it still ran until we decided to make a dumprun trailer with it. (which is when i found all the carnage under the heads).

So what you’re saying is, I said something was “easy” and then proved that it still isn’t? 😅

Had a friend who put a hole thru the side of the block and still drove it several miles home.

I have heard multiple stories of slants driving around for extended lengths of time with one rod having exited through some extra block ventilation 😅

So I give you that name and said goodbye, I knew you’d have to get tough or die

And when I have a son, I’m going to name him… JIM! Or BOB! ANYTHING BUT SUE!

Wow… this must have been a fun pastime for people make in that time, because I’ve seen at least one other video of blowing one up. It took a lot of work. Haha.

@@DeadDodgeGarage It was great! It didnt want to die though needed help. We had to make room the 383 though!👍

Yeah we were buying deck paint and plants. Haha. You didn’t say hey? What the heck?!

​@@DeadDodgeGarageYou NEVER want to meet your heros.😊I'm surprised you didn't know that....

Ok, I know *why* it was there - but why did they feel they needed it there? Lol. The engine was never seized. It wasn’t tight enough to turn the engine with either. Awesome! I hope so! Haha. You bet.

The 80s slants are the best ones! They just run and sound great. I’ve always been impressed.

Well we already built an aluminum four barrel manifold, and I have an EFI system for it. I need to figure out the turbo side and piping, and then we’ll have a show…

Yes. Overkill is exactly what I said. We were going to look for an A body 8 3/4… but this Dana cost way less than $3000, on a crate, ready to go and set exactly up how we wanted it. So here we go!

And it rode around on top of the piston banging little dimples in it until it flew out the exhaust valve. Now the evil nut is sitting in the muffler telling mice of its wild ride....

If that’s what happened, how could we have no impact marks whatsoever on the cylinder head? I’ve seen what happens when little pieces of valve seat bounce around in a modern Hemi, and it’s very impressive. This is an iron head instead of aluminum, but I still think a chunk of metal jammed into the head and halves by a piston will leave some marks.

Yeah me too. I ran out of time unfortunately.

Yes! I’ve never seen it put together wrong so didn’t know to mention it.

It comes sooner and sooner all the time. Haha. It’s 1:00 AM Sunday morning here.

Oh yeah… I’ve done my share of slant fuel pumps too. My ‘73 Swinger was running like absolute garbage pulling away from a gas station one day in like 2009. So I pulled over and found the crankcase was massively overfull… turns out when the fuel pump diaphragms start going, they can continue to work well enough to run while pouring fuel into the oil! Cool trick. So I limped it to my mom’s house a few blocks away, got a new one at the parts store, and changed the oil… that contaminated oil/gas is *still* in an enclosed oil drain at her place. That’s my bad.

Yeah that thing has seen some stuff. I must have put ten clips on it. It’s my fault for using chrome tools with it and ruining the dingus end. I have been slowly switching to Milwaukee stuff because my Mac Tools rep moved away and we haven’t gotten a new one. But that 3/8” impact is an absolute reigning world champion. The Mac cordless tools are made by DeWalt and use the same batteries, chargers, etc., but come with a three year warranty instead of one. That one has more than outlived its warranty, it’s been dropped, it’s been thrown, it’s been dunked in coolant. Seriously good stuff.

I am fully aware of and familiar with piston pin offset. The cast in area that the pin should be centered in is offset. The pin in this piston is drilled way off center of that hole, such that the offset appears to be much more - on one side only.

No, the overhead is plugged directly into the wall. But it’s on the same circuit as a few of the lights.

Oh I have, a couple times…

Seriously?! I haven’t seen that, but I did see a clip of that Holley sponsored turbo slant build running before it had a turbo. Wonder if you mean that one. It’s absolutely amazing and beautiful - and it made me a little grumpy, because a turbo slant video series has been in my plan for quite a while, and they kinda took the piss out of it. Haha.

Interesting, it didn’t sound that way to me. It sounded… broken

I guess you haven’t seen a lot of my videos then. Lol. I am a big proponent of mostly stock engines and usable torque for the street. I’m not a big horsepower guy, and have never dyno’d an engine I have built. I’m all about home grown performance, and not spending a fortune on go fast parts. I may be one of very few RU-vidrs you will find that has been involved in a fuel economy oriented classic build or two. I’m also one of few people who will tell you that modern drivetrain in a classic like this is a mistake - and not because I hate or fear modern stuff. The exorbitant cost alone far outweighs any savings from fuel economy gains you will see, unless you drive this car thousands and thousands and thousands of miles. That may be your goal in such a build, and that’s great - but then you come up against another issue, which is the reliability of the electrical system and the fuel system used to make the conversion. And the difference between a slant six and your Pacifica engine is that the slant six doesn’t need a space station’s worth of electronic controls to run. In fifty years, which of these engines will still run and be reliable? My money is *not* on the Pacifica. My brother has documented thousands of miles in multiple V8 powered A-bodies, logging fuel economy in the low 20s MPG range. You might beat that with a modern drivetrain swap - but at what cost? In my book, these cars are best enjoyed in a mostly stock or period correct state. They are simple, reliable, easily diagnosed when things go wrong, and lots of fun - even the slow ones. That’s my take on this anyway. It’s only based on sixteen years of experience with these cars in every flavor there is - from stock slant sizes to modern Hemi swaps, I’ve tested these theories a lot.

Not to pile on, but I remember a video from Onelonelyfarmer talking about buying a godzilla powered F250 vs. the diesel-powered F250. He said that when you compare the price difference between the packages, you can buy a lot of gasoline. In his mind, the gasoline powered package is overall more economical despite getting worse fuel mileage. The same can be said for weird drive train swaps. You can buy a lot of gasoline for the money spent on the swap, even an aftermarket overdrive transmission behind a factory engine.

It wronged me! Screw that thing

​@@DeadDodgeGarage For that impact Had besmirched you For the last time 😂

It's an IMPACT wrench, they're MADE for dropping. It's right in thr name!

On the contrary - I’ve never seen one that *wasn’t* nylon, and I’ve never had that problem!

Me too. I should have cleaned the chamber too, I realize that now. But I saw no evidence of impact or damage there.

@@DeadDodgeGarage That IS odd.

@@dantupper1784I think it ingested a small alien vessel which then fired a photon torpedo at the oncoming piston!

@@robinelston5966 Was kinda thinking of a bad piston heat-treating, maching error, wrong size piston (that factory a,b,c,d thing) or rings. Being 2024 and all- sure, why not?-ad mini aliens & photon torpedo's. At the rate they are extending the B-52's lifespan, Ol' Grandpa BUFF will probably get upgraded to photon torpedo's & warp drives next retrofit

@@dantupper1784😅I love BUFFs they fly over our Bossier Parish property all day long.

…what?

Oh I’m sure you’re right. Haha. Some smoke and blowby is certainly within factory specifications. I know - the early dash is really cool. But it wasn’t exactly up to use what car was donated.

Well there we go. I have heard that oil consumption can lead to pre ignition. So I guess the question is what was the original sin - how did the oil end up in there? Obviously we can see the terrible ring seal now, but was that before or after the piston cracked?

@@DeadDodgeGarage Hard to say for sure, but I bet here was a "smaller" problem than the crack, that began a domino effect. I have had many engines that got tired and burned oil start detonating really bad under load. The pitting on the piston crown is detonation for sure, and the way the crack and rings look my guess is they are also detonation damage. I had one tired engine detonate so bad it eventually holed a piston.

@@timmcooper294 I’ve heard it can get to that point. Cool! This makes good sense to me. The last engine I took apart with obvious detonation damage had it in 3 holes I believe. Just thought it was interesting to see in only one, and to that extent.

You know, I’m well versed with those stampings on big blocks, but I’m almost ashamed to admit I don’t know where they would be on the slant. And I seriously don’t know why I didn’t go looking for markings on a bearing and show that - as I have in my recent Hemi teardowns. I was definitely in a hurry at the end of filming the video. That’s unfortunate.

“Allegedly” Yep… I allegedly fed a slant six half a can of ether to get it started after sitting for years as a teenager, and found out what the inside of the block looks like. I wish I still had the chunk that came flying out.

If I ever find one… I will. But they are very rare in these parts.

Isn’t that neat?! I don’t recommend using the reverse feature though. 😅

Tube or washer - not both.

I’m glad someone enjoyed me leaving that in 🤣

Everytime I see a Slant Six I think that.

I too have had the same thought, many times… I know someone out there has done it but I’m still tempted.

Their manifolds sure are! But I built my own 😁

Did they nuke it from orbit?

Impossiburu!!!

I'm right there with you on the erosion once it cracked and let combustion gas through. That could also be the source of the noise, combustion gas expanding into the crankcase.

We still need to make the “Leaving Tower Of Power” shirt…

@@DeadDodgeGarage the replacement tower of power, we'll be watching. With that new intake manifold and small 4 barrel? Did you say headers? Or just the re and re.

Alright, yeah, that checks out. I’m kinda deaf, and/or have selective hearing 🤣 we were incognito in the normal people family car.

What are we talking about here?

…sorry?

Aaaaaahh, *that’s* what it’s for!

Love your reticle!.....You know what I mean.

@@jeffhutchins7048 I have three hunting rifles with it. Two from Leupold and one from IOR/Valdada. Nothing better for my hunting.

Every oil change? Obviously there is a spec for adjustment but I didn’t think it was that frequent.

But why are there no marks on the head/valves?