After dragging home the $400 400ci Chrysler big-block for our 1983 Imperial, we knew without a doubt that we were in for a big engine build…not the blower-and-power type of big build, but the strip-it-all-down and pay-the-machinist type of big build. The 1975 400ci engine had been yanked from a Mopar sedan that the former owner could not quite remember, so going off of visual clues only, this is a non-Lean Burn 2-bbl model that was rated from the factory at 175hp and 315 ft/lbs of torque. And since we already knew that the 2-bbl, intake manifold, and stock exhaust manifolds were going to the scrapyard in favor of some better pieces, we weren’t bothered by the stock numbers. But enough hemming and hawing, let’s start ripping into this puppy and see just how bad things are inside the engine that has sat for several years in a semi-trailer. Follow along with us…
Here’s our lump of a B-motor, pre-teardown. The paint was still good on the intake and valve cover bolts…if anyone has been in this 400ci before me, it doesn’t show it. That’s good, right?
No surprises under the valve covers: old, cooked and dried oil coated the rockers and valve springs, and only a touch of surface rust appeared near open valves.
Surprisingly, the exhaust manifold bolts, for the most part, gave me little trouble. This one nut, however, did. After rounding off with the correct 9/16ths socket, I tried about every redneck trick in the book (including heating and bashing on a 1/2 socket) before I caved and bought a bolt extraction kit from Sears. Off like a charm.
Once the heads came off I may have freaked out a little at the sight. Most of this cleaned up with some WD-40 and a scrub brush. This is the right bank, and cylinder #2 (2nd from right) is the biggest worry on this whole project. It’s not visible in the photo, but the “top” of the cylinder has some worrisome rust. Yikes. (The oil you are seeing is the Marvel Mystery Oil I poured in a couple of weeks ago)
The right bank looks worse than it is. Here, most everything cleaned up. Note Cylinder 3 (2nd from left). See that object in the oil? That is a GARDEN SLUG that somehow managed to get into the cylinder. I don’t think I’ve even heard of something like that.
Draining years-old oil with a questionable background…sure, why not? Clotted oil, the remains of the valve seals, tons of carbon, bits of plastic, and whatever the hell else was in the pan oozed out slowly.
…at least, what would ooze out did. The remnants in the pan proved extremely thick and needed a thin Bondo paddle scraping to come out. Notice all of the bits in the bottom?
Nylon teeth for the timing system. No idea when all of this broke down, but it looks like little to no damage occurred. We will be replacing the oil pump as a precaution.
Down below, things actually look pretty decent. The oil pan has never been off of the engine, and the gasket had the consistency of a cooked cracker as it was nearly chiseled off with a plastic scraper.
After fighting off the water pump, crank pulley and harmonic balancer, it was time to take a good look at the timing gears. They were there…
…but were so shot that a slight pry caused the entire chain to jump teeth and fall off. Low-mile, she ain’t.
So what happens next from here? The pistons need to be knocked out of the cylinders and the crank needs to come out for inspection. Once that is done, the 400 is going to the machine shop for measurements. Cylinder #3 will determine what happens next…it’s the most damaged, and we need to determine if the block is useable or not to find out what happens next. Such is the luck for buying off of Craigslist, but this is the way it goes for someone shoe stringing a car together on a low budget. If the 400 is a dead player, we still got a 727 automatic out of the deal, and we can use the big motor to mock-up the engine bay while we source a new bullet. Next update, we will see if our silver brick gets a new motor sooner or later!
If the block’s toast, I may have a spare 400 block sitting around I think. Never did care much for the 383/400 engines. Kinda like a 396 Chevy, just didn’t make the power.
That’s going to be a cool project…. looks like you had a bit of a miss with the oil drain pan! 🙂
A 400 is a good candidate as a stroker build..just sayin 🙂
Amen. If you gotta rebuild anyway there is no reason NOT to stroke it.
Absolutely!
If this block gets the okay, it’ll be perfect for making a stroker.
If that timing gear has all its teeth, then it’s been replaced before if you found some teeth in the bottom. Which if it has been replaced AND has that much wear, you may have a million mile motor on your hands! =D Or at least a 300k+ one.
Stock stroke,mild cam, two turbo’s? Jeykll and Hyde!
Hopefully the slug is not an omen.
The slug was obviously a low compression slug.
Seriously though as long as that cylinder will clean up and the block sonic checks,use your journalist’s cred to get a stroker put together.
Face it, those pistons have to be replaced to make any kind of power, you’ll be half way there.
Call up 440 source and offer some ad space. Cmon, you know you want to!
I’m feeling like a 451 stroker build is too obvious not to do.