Bosbury1

Looking to pull my 4.0 with 340,000 miles. I have several questions hoping the forum can assist. I'm the original owner of the truck and want to rebuild the motor (all stock) by a reputable machine shop. The question I have is so many posts talk about master rebuild kits are a mixed bag as it relates to quality of components. What manufacturer of internal parts should I be focused on? Also, should all parts of the motor be replaced with the exception of the crank? Obviously, if any component is bad it needs to be replaced, but all the components are 28 years old. My end game is to have a completely stock motor (with original numbers) that will last for many years. Thanks.

agreen

Generally:
Pistons, rings, bearings, seals, gaskets, timing set, oil pump

Reality:
The teardown will reveal what else has to be replaced.

Bosbury1

Good information. Any recommendations as to a good machine shop in the Dallas, Texas area?

Bosbury1

See above. Dupped in error

Bosbury1

What brand name of internal parts should I purchase?

agreen

Sealed Power, Fel Pro, Mahle... that's off the top of my head. I've never had a problem using any of their stuff. It's the weirdo name brands that aren't well known that are the problem makers.

Old Man Minimalist

I used to work for TRW/Federal-Mogul. I sold ton's of engine parts to shops all over the country. I also built a few engines on the side for personal vehicles. LIke agreen says, look for the better brands. Don't go cheap on the components. You don't have to do the high end race/performance stuff either. I'll add TRW also, specially if you end up needing pistons.

The key, as it appears you are already working towards, is a reputable machine shop. If you are going to build the engine, make sure you double check every clearance. Don't take the shops word.

And scrub the cylinders out with hot, soapy water twice at least! Don't use carb cleaner or brake cleaner or any of that crap. Dawn dishwashing soap works great. It should be clean enough that a white rag will wipe through and stay white.

I would also add a camshaft and lifters at that many miles. Keep us posted on how it goes.

Bosbury1

Again, thanks for the information. Spoke with 3 machine shops today they could not tell me what they would do other than rebuild my engine. Really, what its a money grab.

sstout

I just had my engine rebuilt by a machine shop/builder. A good shop should be able to give you alot of info. When I dropped it off we talked about the current state of the engine, what I wanted out of the engine, and what the machine shop recommended. Then during the build we talked about what he found wrong with the engine (piston slap), what he recommended for new parts, and what he recommended for machining. I ended up with a motor bored .30 over, and a slightly larger cam with all new internals except the crank, and the longblock fully reassembled ready to drip in. It even included break in oil. My point being, a good shop might not tell you all their assembly secrets but you should be able to have a very detailed conversation about what parts and what the build should be. I'm not in the Texas area so I can't help you there, but good shops are out there

Bosbury1

Thanks for the information. Will continue to do my due diligence.

Bosbury1

Was wondering if somebody had an Excel spreadsheet of all parts used to rebuild a stock 4.0. Thanks.

Old Man Minimalist

Not a bad idea to have one. If no one has one, it wouldn’t be hard to create one and offer it up. Could use it as a checklist with columns for part, brand, source, cost, etc.

eventually I’ll be rebuilding mine. If we don’t find something by then, I’ll create one. Or maybe I’ll be bored at work one day and I’ll make one.

5-Speed

Edit - page 3 list part numbers and everything

You can poke through one of my build threads from my last Jeep I rebuilt the engine on. I did a decent write up on the engine build portion with everything I went with.

https://www.cherokeeforum.com/f46/pr...240930/index2/

Old Man Minimalist

Page 3 on the above thread? I couldn't find it. Can you tell me the post number?

5-Speed

Post 35 in the link above.

$20 - Pair of motor mounts DEA A2572
$25 - Lifters Engine Tech L2011
$12 - Intake/exhaust gasket Felpro MS93094
$15 - Timing chain Melling 385
$5 - Timing chain guide OMIX 1745370
$22 - Head bolts Ebay CPW1441
$68 - Crank and rod bearings Clevite CB960A and MS1947A (Do not cheap out on bearings!)
$29 - Lower gasket kit Felpro CS8169-3 (this is for 99 and earlier. Different rear main seal for 00 and up)
$128 - Pistons and rings Ebay CPW3758
$12 - Champion copper spark plugs
$10 - Piston ring compressor OEM 27039
$0 - Machine work (bore, balance, cam bearings, surface, turn crank and piston swap)
$??? - New head (price unknown ATM. Waiting for machine shop to tell me)

$346 - Grand total so far