Rebuilding a 5.9 Magnum for fun/learning

[svdsinner]

The 5.9 Magnum in my '98 2500 died and is locked up. (I assume it threw a rod) I'm hoping that in the spring, I will get some time to pull the engine and see what happened to it. I've never done a full engine rebuild but would love to use this as a low-stress way to try doing it. From what I have seen online and at local parts stores, I can get a rebuild kit (pistons, gaskets, rings, bearings, etc.) for $400-ish. There are probably another $500-ish of parts that may/may not need replacement (Cams, heads, crankshaft, etc.) No idea what machining will be needed, but I'm guessing $3-400.

After I finish it and test it, I'll be selling it. My motivation here is NOT profit, but to learn about the process. I'd like to make the end-product a quality deal for whoever buys it and be able to sell it for a bit more than the parts I'll be putting into it.
1) When I tear it down and find out what broke, are there things that should scream "This engine is not rebuildable!"

2) If I keep it stock, what would a reasonable price for it to sell quickly? I see tired, high-mileage used (non-rebuilt) ones are $800ish on E-bay.

3) Are there upgrades I should do to it (that would likely make my money back) to make a buyer happier?

4) What level of performance should I target if I want a reasonably quick sale? Stock? Mild performance mods? I know that realistically, people interested in huge performance don't drive trucks with old 360 Magnum engines in them. But would they want (and be willing to pay for) something with better towing grunt?

 

[LeesEvoX]

I cannot answer questions 2 and 3.

But for 1. you want to look for cracks. lol. this can happen in the coolant jackets around the cylinder, or even in the block if you really went out on a BANG! Also be sure to check what the factory cylinder liners look like. Look for vertical grooves and gouges here. some of these can be taken out by boring the cylinder. But you can only do so much until you need to remove the liner completely, and go with an aftermarket sleeve.

Also, when have a failure like this. Which could include small bits of metal being deposited everywhere, i always change stuff out like oil pump, and oil coolers (If equipped). It would be pretty ****** to do all that work, and have a oil pump clog up and toast everything.

For question 4. i personally would keep stock as much as possible. Building a stock QUALITY engine will always bring more buyers. Because it will give them confidence to modify it themselves!

If you do end up doing this. Firstly good luck, and secondly. make sure to post it on the forum! This will be a great experience for you, and IMO is the only way to get a real appreciation, and knowledge for how these giant chunks of metal take you where you need to go day in, and day out. i love all types of combustion engine. because they are just so interesting to me.

Whether that be the giant 6.4l Merican V8 in my power wagon. Or the little 2.0l 4 banger, GIANT turbo in my old evo.

 

[ViolentMouse]

1.) If it's locked up... the cause should stick out like a sore thumb... this is probably one of the easiest motor to work on. It's either seized bearings, or it shattered a piston and the rod cut into the cylinder and murdered the block, or it dropped a valve, but you would be able to spin it backwards if that was the case.

2.) if you keep it stock, it's still a rebuilt magnum motor that was assembled by a rookie and not a shop with a pedigree. Nobody will pay more than $800 for it. look up mabbco motors. you can get a rebuilt 5.9 magnum for under $1000, and they do this for a living. (and still get bad reviews lol)

3.) Simple answer. No. You will never make any money back on parts for a magnum. But upgrades that make everyone happy include: Hughes plenum pan. Clevite bearings, forged pistons, EQ heads with stainless valves (assembled by hughes so you don't get sticky valve guides) The list could go on forever.....

4.) You are not going to get a reasonable, or quick sale. pre 2002 magnum blocks with 3 motor mount holes are like locusts... you can find them in field all over america and most people looking to get a new magnum motor will be of two varieties.... either you have a gearhead who wants a ****** core to turn into a hot rod motor, or you have someone looking for a low mileage salvage motor to replace the blown motor they have. Very few people by rebuilt motors from non pedigree sources, and the ones who do don't have enough money to make it worth your time and effort.

Best bet, strip the motor down, see what it needs... if any of the cylinder walls have deep gouges... toss it... move on. If the cylinders still look decent, go ahead and rebuild it with the intention of either putting it back in the truck and using it yourself, or donating it to a local high school auto shop program so that everyone else can have a turn tearing it down and putting it back together.

Best suggestion was in the above post. If you decide to go through with it, make a post, good luck, and have fun doing this for yourself knowing that it is not going to earn you a single penny.

 

[Robeffy]

I built my first motor ( GM 400 sbc ) from scratch ( the rods were installed in the pistons and the cam shaft bearings were installed for me - the first needs a press, the second needed the bearings lined up with the oil feeder holes in the block ).

Get a good manual. Read the section before you start.
Read it while you start.
Do a bit, reread it make sure you did it right.
Take your time.
Read a few articles on the internet.
Take your time.
Keep everything totally clean, all the tiime, and keep it covered when not being worked on.
Get a good torque wrench.
Get the right tools, like piston ring compressor, ring expander, cam degree wheel.

Everything is made to go together, so, it will fit, if it's assembled right.

I file fit my piston rings, individually, I deburred the oil gallery holes, I chamfered the crank oil grooves, I deburred flashings, if it could be checked, it was checked.

It ran like a top when I started it, and I drove it for another 12 years, revved it up over 7000 rpm more than once.

The "mechanic" I bought it from left a rag in the crank case, installed the wrong cam, generally eff'd it up.

You can do it, and you will learn a ton, I would keep it stock, as you are going to sell it anyways..

 

[dutchie2010]

Hey guys. Looking to add some HP to my 360 magnum in a 2001 2500 with the OEM injectors. Anyone here have some experience with that? I hear Merc225hp knows a thing or two. Anyone able to connect the two of us? Thanks in advance!