Contemplating rebuilding a spare motor

Bigmac

Rather be in 29 palms.
Supporting Member
Joined
Mar 11, 2018
Messages
714
Location
Oklahoma, USA
I'm considering picking up a used 4.0 and starting to build up a fresh motor.

I can pick up a 2000 4.0 about an hour from me for 175 bucks. It has a wrist pin rattle and need to be rebuilt, apparently the head was redone 4k miles ago.

I'd like to rebuild it but not sure what I'm getting myself into.

The initial block and all else is pretty cheap, but I'm thinking I'll just put a Clearwater head on it, and build it up with reliability being the ultimate goal.

I'm competent with a torque wrench and I don't mind gaskets and things like that but I'm obviously not a machinist.

Assuming I need to get the cylinders honed and have the block decked plus other decent quality rebuild parts what would be a good ballpark estimate on completing something like this?
 
I've been wanting to do this for decades. More specifically a stroker.

Wonder how much that would add to the parts list? I'm thinking about that too but I don't know what I don't know and I'm afraid I'd be diving into something I'd never finish.

For 175 bucks I want to buy it in case I get around to it later but being active duty I move a lot. I've only got 1 more year here and I'm not sure what the process is to get DMO to move an engine.
 
When you PCS they reimburse you by the pound...

I've been contemplating the same thing...no idea how long my 4.0 will last...but I think when/if it comes time I'm going with another engine...either a 5.2 or 5.9, an LS or Netgain 120s.

-Mac
 
When you PCS they reimburse you by the pound...

I've been contemplating the same thing...no idea how long my 4.0 will last...but I think when/if it comes time I'm going with another engine...either a 5.2 or 5.9, an LS or Netgain 120s.

-Mac

Unless you bust max weight allowance, which I always do. In that way the weight of the motor deducts from what I get back as reimbursement. Since the truck camper has no axles I get to count it as Dity move weight 🤫.

My concern was more about the hired help being able to palletize and transport a half built motor without fucking it up.

Guy I know just moved to the area, first thing they did unloading the truck was drop his 48 gun safe off the loading ramp and break the lock and handle off the front. And that's how it goes when your standing their looking at them.
 
Guy I know just moved to the area, first thing they did unloading the truck was drop his 48 gun safe off the loading ramp and break the lock and handle off the front. And that's how it goes when your standing their looking at them.

When I moved from Boise I had to unload my gun safe by myself... actually slides pretty easy on its side on moving blankets...must have had a rock or something and it left a giant scratch down the side.

If you're in OK I'd get in touch with Puddins Fab Shop and have him help you do the rebuild. Good content for his channel and you could get it done and installed.

-Mac
 
  • Like
Reactions: Bigmac
I vote stroker--and a mild build will cost not a ton more than than a 4.0 rebuild. Basically the parts cost of crank, rods, pistons, and injectors. All the other stuff is the same until you start getting into MAWs like cam, head work, etc.

I PCS'd 3 RB engines (I6s), 2 transmissions, 2 rear ends, an entire interior, and a TON of odds and ends back from JDM land. I packed a lot of it up first in gorilla boxes and when they showed up to move me, they asked "what's in those boxes?" I replied "A weight set and scuba gear. And those cases of beer sitting on top of the gorilla boxes are for you guys." No questions were asked and they moved my weight lifting set and scuba with out issue. 😎

For the actual packing, I wrapped each engine or whatever in a couple of big trash bags. Then I lined the gorilla box with plastic, and used expanding spray foam mixed with big chunks of garbage styrofoam I had lying around to take up space to fill it about 1/3 of the way up, plopped the engine in, then filled it the rest of the way up and zip tied it shut. No way anything was getting hurt. Bonus points for making it REAL hard to check what was in there. They were real strict on moving hazmat in Japan so I wanted to avoid any potential complications.
 
If it's already had the head done in the past 4k miles would I need to have the deck re-done and cylinders honed? I just don't know what a head job would typically involve. I also don't really understand if a block gets decked every time the head comes off or just if it's warped after a considerable amount of miles.

Truly showing my ignorance here I know.

@kincaid.0678
 
I vote stroker--and a mild build will cost not a ton more than than a 4.0 rebuild. Basically the parts cost of crank, rods, pistons, and injectors. All the other stuff is the same until you start getting into MAWs like cam, head work, etc.

I PCS'd 3 RB engines (I6s), 2 transmissions, 2 rear ends, an entire interior, and a TON of odds and ends back from JDM land. I packed a lot of it up first in gorilla boxes and when they showed up to move me, they asked "what's in those boxes?" I replied "A weight set and scuba gear. And those cases of beer sitting on top of the gorilla boxes are for you guys." No questions were asked and they moved my weight lifting set and scuba with out issue. 😎

For the actual packing, I wrapped each engine or whatever in a couple of big trash bags. Then I lined the gorilla box with plastic, and used expanding spray foam mixed with big chunks of garbage styrofoam I had lying around to take up space to fill it about 1/3 of the way up, plopped the engine in, then filled it the rest of the way up and zip tied it shut. No way anything was getting hurt. Bonus points for making it REAL hard to check what was in there. They were real strict on moving hazmat in Japan so I wanted to avoid any potential complications.

"Me, the boy, 2 droids, and no questions asked."
 
Like SkylinesSuck said. Only real cost difference in a stroker is a late model 258 crank and stroker pistons on your 4.0l rods.and 24lb injectors. Everything else is chasing hp.

I did what you're contemplating. I found a compatible year motor.tore it down and sent it out to get cleaned and bored.went ahead and had my machinist assemble the short block since he gave me a buddy deal on it.

Then swapped it in over the course of a few days before my tired 4.0l could give out
 
When I moved from Boise I had to unload my gun safe by myself... actually slides pretty easy on its side on moving blankets...must have had a rock or something and it left a giant scratch down the side.

If you're in OK I'd get in touch with Puddins Fab Shop and have him help you do the rebuild. Good content for his channel and you could get it done and installed.

-Mac

pvc pipe is the way to move a heavy gun safe. just needs to be a large enough diameter to clear the threshold of your door. works like a charm!
 
  • Like
Reactions: macleanflood
If it's already had the head done in the past 4k miles would I need to have the deck re-done and cylinders honed? I just don't know what a head job would typically involve. I also don't really understand if a block gets decked every time the head comes off or just if it's warped after a considerable amount of miles.

Truly showing my ignorance here I know.

@kincaid.0678

As far as decking the block or milling the head, it's something your machine shop will check and tell you if you need. Just plan on boring it .030 over and buy pistons accordingly unless you want to try and reuse the stock pistons on a stock 4.0 build which you could, but I wouldn't bother considering all the time and effort you are already going through just to save a few hundred bucks. Add far as the head goes, ask your shop how much to go over it for you and decide how much you trust the word of your cousin's roommate's sister's neighbor on it being refreshed and what all that entailed.
 
I built a few hot rod smallblocks decades ago and am not the most mechanically inclined person. Get a good manual, an engine stand, torque wrenches, use a good machine shop, follow instructions to the letter/thousandth, and take your time. Nothing really difficult about it except for what the machine shop will be doing.
 
  • Like
Reactions: Bigmac and Rickyd
I rebuilt the engines for a 280Z and a 300ZX before I was 21, all based on what I'd read in books and the internet, such as it was in 2003. Neither of them blew up, though the first one seemed to consume a lot of oil. I promise you know now way more than I did then.
 
If it's already had the head done in the past 4k miles would I need to have the deck re-done and cylinders honed? I just don't know what a head job would typically involve. I also don't really understand if a block gets decked every time the head comes off or just if it's warped after a considerable amount of miles.

Truly showing my ignorance here I know.

@kincaid.0678

I didn’t deck my block. I went over my head myself. I replaced the exhaust valves because one valve stem seemed slightly bent. I replaced all the valve stem seals and lapped all the valves. If you haven’t had any issues sealing up your head gasket I wouldn’t think you’d need it decked but I’m by no means a professional lol if you’re replacing pistons or even rings it’s best to hone the cylinders to get the new rings to seat. I bought a bore gauge to check the cylinders out to see if they were in spec. Almost everything you need to know on rebuilding these engines is in the FSM short of cam bearings but they’re pretty straightforward with the right tools.
 
If you need to tool up it won't be cheap, maybe even more expensive than just buying one, but the end result will be satisfying.

After parts I wound up breaking even on a 241 tcase I built. It was not the cost break I expected but definitely rewarding.

When you say, " tool it up" what specialty tools are you referring to?
 
Ok makes sense. Yeah I see engine stands and cherry pickers on FB marketplace for cheap all the time. But yeah would be an additional cost. Thanks