Thank you, that did clear a lot of questions up for me.I will be going with the 5.2 system.

I had the opportunity to learn about the early Bosch fuel injection system way back in high school auto shop in 1973, while it was still very new. The instructor I had that year was very up on the new systems of the time. Then, I was a Chrysler dealer tech in 86 & 87and was brought up to speed very quickly through the dealer training program of that time, but then I opened a welding shop in 94. I didn't pay much attention to the transformation of the injection systems after about 92 and didn't get very involved with it again in about 2010. Then it was involving the early 90s to mid 90s systems, and as noted, information was pretty inconsistent.

I'm OK with throwing the throttle body system away, but it did work flawlessly for me for many years. Every vehicle here has been Chrysler EFI since 2011. My 49 Pickup has an intact system from a 96 Dakota. I have no interest in getting involved with the modern security code systems. Too many things just got stupid after about the 2010-2012 model years.

The free 5.2 update:
I was able to get to my son's place and check out the 5.2 in the Ramcharger. I have mixed emotions. The build date on the Ramcharger was 8 of 91 making it a very early 5.2. It appears to be very original. The mileage is unknown, there is no instrument cluster, but even if there was, the truck has a snow plow on it, so any mileage wouldn't be accurate anyway. When you plow snow, almost 1/2 the miles you put on are in reverse and the odometer won't register those miles. Its hard to say when the plow was installed on the truck, but from past experience, I suspect it lived several years before the plow was added. My guess is that the plow was added in the last 10 years.
The motor has no ran for at least a year. When my son got it very early last spring, he messes with it a bit to try to get it running, but then quit. Nothing has been done since then, except the robbing of some interior parts. So that is the back story, everything we know about the 5.2.

The radiator is full. The oil is low (as in barely touching the dip stick). Other then the air cleaner wing nut not being on, the motor is complete, everything is there. The driver side exhaust manifold has the y pipe wired on, looks like the studs are still there, so that is interesting. It doesn't look like the exhaust manifold bolts will ever come off, and the manifolds themselves are pretty crusty, the diver side worst then the passenger side (the highway departments around here salt the center line on the highway first).

I'm starting out with a compression test, so I'm pulling all the plugs first. Start on the passenger side (that was where i was standing). The outside of the plugs say they have been there a long time, to the point the outer lower 1/2 was rusty. The plug part in the motor told a different story. The electrode and the strap all had crisp sharp edges, like new plugs have. The gap looked to be on the small side (but all 4 were the same gap) and the porcelain was sooty black. Onto the other side, the # 1 plug was shiny new, the # 3 plug was older, but not as old as the plugs on the other side. # 5 matched the plugs on the other bank. The # 7 plug is a problem. These plugs are the small ones that need the 5/8" socket. That all also have that tin shield around them. There was a build up of crud around the plug, the socket couldn't even reach the hex on the plug. In my infinite wisdom (and shear laziness), I decidied i should check the compression on the other 7 and see if it was even worth the effort to pull that last plug.

Another issue was since the dash is missing, and I have no idea how much other stuff may or may not be disconnected, I opted to connect jumper cables onto the the starter wires and the ground cable to the motor. I would touch the starter solenoid wire to the positive jumper cable to crank the motor. As one might expect, those connections were not the best. The starter would turn the motor and almost stop when it got to the cylinder with the plug still in it. At least I know that one has compression... I'm looking for somewhat consultant numbers, and I really don't car what they are unless they are really low.

On the dry cylinder walls, the #1 cylinder, on the first bump hit 60 psi, and 75 on the second bump. #3 cylinder, pretty near 60 on that first bump, almost to 70 on the 2nd bump. That was about the time I considered that those cylinders were probably really dry, the motor hasn't even been turned over since early spring. I brought a pump oil can along, so I gave all 7 open cylinders 3 pumps of oil and cranked the motor over a couple times. Then i restarted my compression testing. Another note, I did not record any numbers, and I wasn't watching the number too close. Starting at #8 cylinder, and moving towards the front. first bump, near 75 (the motor still nearly stops turning when it hits the cylinder with the plug in it), 2nd bump, near 90. # 6 cylinder, 1st bump, 90, 2nd bump near 100. #4 cylinder 1st bump 90, 2nd bump 100. #2 cylinder 1st bump, 80, 2nd bump 90. Other bank, #1 1st bump 80, 2nd bump near 100 #3 cylinder 1st bump near 90, 2nd bump 100. #5 1st bump 90, 2nd bump near 100.

Time to see if i can get the plug out of #7. Recruiting a light, looking through the tin shield, I can't even see the hex on the plug! Recruiting a hammer and thin blade screwdriver, and compressed air, after 3 rounds I managed to get enough of what looked like dried mud, cleared away I could get the socket over the hex. I couldn't put enough force on the standard 3/8" ratchet to break the plug loose. I don't really want to break off the plug either. Since I had an oil can with me, I pumped some oil around the plug base, figured I would let is soak into the dried mud a bit. Later I'll go be with some penetrating oil and see how I fare with getting the plug out.

I am open to ideas on how to get the plug out without pulling the head if possible.

Conclusion: If I can get the plug out without pulling the head, I think I'm going to move forward pulling this motor out of the Ramcharger. If I can't get the plug out, I'm going to move on to the next 5.2. The plan was to install a good running motor because the car won't likely see more then 2,000 -3,000 miles a year. I don't need to invest the price of a rebuilt motor into a car that will be lucky to see 30,000 miles in its life. If I have to pull the head to get the plug out, that snowball will grow way too fast. I will be farther ahead to buy a running 5.2 then to invest into this one.

Iirc, those plug shields press into the head. You can probably collapse it and pull it out for better access to the plug.

If you do break the plug, getting the porcelain and electrode out is important. The threaded end usually come out fairly easy with oenetrating oil and an easy out.

Only real thing I've seen on the magnums is clogging of the oil pickup. Pull the pan and give things a look.

Note, it may be worthwhile to diagnose and fix the running problem with it still in the truck.

I will look into it not running a bit deeper before the motor gets pulled. By a quick look at the wire harness, corroded connectors or broken wires wouldn't surprise me at all. I also have some doubts about the condition of the fuel pump on the Ramcharger. With the instrument cluster gone, the interior tore apart, and having no idea how old the gas (if there even is any) might be, or the condition the fuel lines may be in, do I want to invest a lot of time getting it to run in this chassis? The truck has that look of "whatever cheap thing we can do to keep it running and get by" all over it, and there hasn't been much done with it. The time frame for pulling the motor before winter hits is growing short.

Are those tubes around the plugs something that I still need (I wouldn't mind loosing them), and if so, can replacement tubes be found?

Once the motor is out of the truck, the first step is pulling the oil pan and taking a look at a pair of rod bearings and a main bearing. Every step will be one at a time, something that may indicate a need for a rebuild will likely kill off this motor. Not knowing the mileage, the next step is an inspection of the timing chain and probable replacement. From there its a lot of parts replacement time because I'd rather do it while the motor is out of the car. Those replacement parts include oil pump & pickup tube, a water pump, and looking at the core plugs. Headers are in the plan, if I can find reasonably priced headers, but at the very least, the exhaust manifold bolts will be replaced and possibly the exhaust manifolds. I'm also planning on pulling the intake to replace the gasket under the bottom plate. You can see why I'd rather not pull the heads off.

The tubes are just heat shields for the plug boots. Probably won't clear headers anyway. Pretty sure they're available if desired.

Pretty sure the early Magnum had a fuel pressure test port on one of the fuel rails. With creativity a electric pump can be rigged if needed.

I don't believe these had a factory anti theft system like some newer trucks do.

As for getting it running in chassis, at this point everything is hooked up. Once you swap vehicles, you add infinitely more potential possible causes of a no start. Doing it this way makes figuring out a potential no start easier. I'd verify fuel pressure and spark. Considering corrosion issues, the coil is highly suspect. They're known to corroded the iron core and crack the housing.

A handy tool to make is a 194 bulb socket (license light, side marker) with some small thin terminals on the leads. This can be plugged into the coil connection and injector plugs to see if the ecm is commanding operation.

Once you know which is missing, it's easier to figure out.

Early magnums liked to crack heads.

Used to be a goof aftermarket stock replacement head available, but I think that market dried up a long time ago.

Yeah they were known to crack between the valve seats but, it never seemed to create any real problems.

I also was under the impression that the cracks in the early heads were superficial, and very seldom had any effect on the motor operation. These motors go 200,000+ miles, cracks and all without issues. I'm entering into this with the expectation the heads are cracked, I'll take that chance. My son has an 02 Ram with a 5.9 Magnum, but it consumes a bit of antifreeze every couple months, and you can smell antifreeze burning. I wouldn't take the chance on that motor.

If I needed to pull the head to get the plug removed, I would expect it to be cracked, and the only machine shop in town won't touch a head with any crack in it. At this point in time, probably the only option to solve the cracked head is to replace it with an aluminum aftermarket version. That is not going to happen with this motor in this car.

I suppose a smart guy would pull the heads to look at the valves and the cylinder bores, but then the snow ball starts rolling. While the heads and the oil pan are off, I might as well....


ruderunner, you talked me into making sure I have a functioning system before I pull it from the Ramcharger.

I've seen plenty of the Magnums run over 300k under abusive conditions. Like I said, the clogged oil pickup has killed a couple. Never saw dropped valves or anything catastrophic. Maybe a tossed timing chain.

Your son ought to figure out the leak. Most common is a tube that feeds the heater hose, water pump seal and radiator seam. None is a deal breaker.

I wouldn't sweat the spark plug yet. There's ways to get them out.

The coolant leak on my son's truck started about 2 years ago. He has had it pressure tested while it was on a hoist and the source of the leak can not be found. There are no external leaks present. That was the point he decided to pull the truck off the road and has replaced it with a decent truck (with an already existing plow ready to go). He would rather keep the old one running well enough to do his driveway for as long as he can before he uses the "new" truck to plow with.

That old truck has been a snow plow all of its life. Everything on the truck is a crusty mess (looks worse then the Ramcharger actually), won't be anything under that truck, and very few things on the top that will ever unbolt again. He bought it for $1500 four or five years ago, knowing its condition, for the primary purpose of plowing his driveway. His ability to use it as a truck for the first few years was an added bonus. He no longer drives it on the roads, it hasn't had good plates on it for more then a year now. He will keep it running well enough to plow his drive, when it fails at that, it will likely be history. His functioning newer truck is in much better shape he can replace the old one for plowing his driveway with very quickly when the time comes. His plan is to get what ever use the old truck still has, out of it, before he puts it out of its misery. For the money he paid for it, its been a good truck, and it has lasted well past what he expected, but every year its conditioned has deteriorated more and more.