Advice on 4.0 SOHC used engine

Hello all,

I recently purchased a 01 Ranger XLT 4.0 4x4 SOHC for $1200 with a blown engine. I found a used engine on Ebay delivered for about $800. The engine has 138k miles. I am going to swap it out myself and have done several engine swaps before. My question is, what should I replace before I put the engine in?

I don't drive a lot, probably 5-8k miles a year. I have the knowledge to do a complete rebuild but believe its unnecessary considering the amount I drive. I do plan on keeping the truck for several years and would like those to be as trouble free as possible.

Currently I am planning on changing the rear main seal / water pump / valve cover gasket and driving it unless you guys think something else is necessary.

Thanks in advance! If you need more info please let me know.

Not to dis hearten you but this SOHC motor is unlike any motor you have probably encountered. At the very least you will want to make sure Your getting a 2001 engine for the swap. Im not evn sure if it matters for 2001 but you will want to replace the entire timing system with an updated timing kit while you still have that motor out of the truck. If you do that you may as well order up a complete gasket/seal rebuild kit because every single little part will need a new gasket.
You could probably cut alot of corners as Im sure you have planned but if you read around the forums you will see many told stories of regret not dealing with some things while they are easy access. Im sure others will have some more sound advice for you. Good luck.

TL;DR
If you can afford a reman engine I would definitely go that route and rebuild the blown one in your spare time or something. Then sell that and make a good deal of your money back.

If you have a lot of time and money it can be done. The timing tool set is around 200 bucks. You can get that back if you sell it when your done. Parts will run you around a grand. looking at a day or two of tripple checking all your work to install it all. That's just the engine.

Yeah I've done some homework and its the first most I've worked with that has one set of timing done on the rear of the engine. I don't mind spending the time and effort of replacing all of the timing guides ect. I also purchased a FSM and feel pretty comfortable with the process and have found a decent price for the special tools needed.

One question I would have is, since there is no current head gasket leak in the vehicle and I take the heads off to replace all of the timing; Can I just block sand the surface with a certain grit instead of taking the heads to a machine shop? If so, What grit would you recommend and in how many steps? I know the MLS head gaskets like a pretty low RA value I believe.

Also the engine I got is a 2003. Everything I read said it should be 100% interchangeable. Worse case I'm sure I could swap intakes if it turns out to be an issue

After researching cylinder head prep I believe I've decided to use 3m White Roloc discs to prep the surface for the head gasket. Has anyone used these and had good luck???

Roloc disk are quicker but you can easily goo up and aluminum head by getting too aggressive.

If you have the time why not a medium flat stone and some tapping fluid.

Less chance of messing up.

Either way be sure to check the face with a machinist straight edge before you put them on to be sure they are true.

Medium flat stone? I'm sure I'm going to feel stupid when you explain but I'm not sure I understand.

Medium grit flat sharpening stone.

http://www.sharpeningsupplies.com/Norton-Crystolon-Bench-Stone-8-x-2-P176.aspx

We use them all the time one the big machines at work to cut stuff down.

It takes time but it works.

head removal not required

badata1 said:

. . . One question I would have is, since there is no current head gasket leak in the vehicle and I take the heads off to replace all of the timing; . . .

Click to expand...

On a 2001 it is not necessary to remove the heads to replace the camshaft timing related components. If the engine has good compression I'd consider just replacing the timing components. That saves the cost of head gaskets, head work, and head bolts. The camshafts can be timed without using the timing tool kit but the kit simplifies the process.

Awesome. Thanks for the help guys. I'm going to just try to leave the heads on and replace the timing that way. I thought I had read somewhere that I had to remove the heads. I don't mind paying for the timing tool kit. I'll just sell it after I'm done using it and only be out a few bucks.

2004 and later

Around 2004 the head or block casting(s) were changed making it nearly impossible to replace the front cassette guide assembly without removing the head.

Definitely don't pull the heads unless there is some internal problem. You can do all the timing components from the outside with the engine out. (Do you know that the replacement engine runs and hasn't already had a timing failure?) Be sure to clean out any bits of broken plastic from the old guides, including from the oil pump pickup screen.

The salvage yard I bought it off of had a video of it running. It sounded fine. I have no other history than that. So I'm assuming at 138k miles the engine still has all factory parts/gaskets installed.

Does anyone know the size/thread of the bolt holes on the back of the engine so I can mount them to my engine stand?

Pull a tranny bolt or look that up. not sure exactly what pitch and size it is