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Questions About 4.0 Engine Replacement

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
Backstory:
I have 2001 Jeep Wrangler Sport and the other day I was on the highway when the engine started to lose power. It wasn’t too fast of first but after less then a minute it was not enough to maintain highway speed and was continuing to decrease. So I pulled off onto the side of the road and it died without me doing anything. Long story short, it wouldn’t start and it was later found that there were metal flakes in the oil. Because of this I’m pretty sure it’ll need a new engine. It has 157k miles but I’m not sure previous owners took very good care of it.

Questions:

Is it better to get a rebuilt/salvaged engine or purchase a new one?

Where are the best places to get a new/used one?

I know it’s broad but approximately how much would it cost to buy the engine plus other parts that are required (not including labor)?

Thank you in advance for anyone to responds to this.
 

P man

Keister Bunny
Supporting Member
Joined
Apr 11, 2021
Messages
1,730
Location
Washougal Wa
I would be hesitant to replace a 4.0 with that few miles..when you say metal in the oil how much are we talking?
 

ejay

TJ Addict
Joined
Dec 29, 2019
Messages
1,879
Location
CA refugee
Years back I bought a junkyard engine with 50k miles to replace a blown engine in my XJ. The engine cost me about 1500. That amount of miles was a rare find even then.

Periffrials cost another few hundred. I did the job myself so no labor costs.

All in all it depends on what you want out of your TJ. Keep it for a while? Restore it for resale? Or use it as a daily beater?
 
OP
JakobT

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
I would be hesitant to replace a 4.0 with that few miles..when you say metal in the oil how much are we talking?
To be honest I’m not too sure. I didn’t see it myself. I just want to be prepared in case it does need replacement. I’m taking it to an actual engine mechanic I personally know on Monday to look more in depth at it so I’ll try and get some pictures while I’m there.
 
OP
JakobT

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
Years back I bought a junkyard engine with 50k miles to replace a blown engine in my XJ. The engine cost me about 1500. That amount of miles was a rare find even then.

Periffrials cost another few hundred. I did the job myself so no labor costs.

All in all it depends on what you want out of your TJ. Keep it for a while? Restore it for resale? Or use it as a daily beater?
Okay, thank you. That’s similar in cost to engines I saw online but with ~100k now because I think prices have gone up.
 

NskLJ

TJ Enthusiast
Joined
Oct 19, 2021
Messages
456
Location
Long Beach
To be honest I’m not too sure. I didn’t see it myself. I just want to be prepared in case it does need replacement. I’m taking it to an actual engine mechanic I personally know on Monday to look more in depth at it so I’ll try and get some pictures while I’m there.
There are companies you can send a sample to for analysis. They will return with a break down of the type of contaminants.
 

NskLJ

TJ Enthusiast
Joined
Oct 19, 2021
Messages
456
Location
Long Beach
I didn’t know about that. I might have to check that out later. Thank you for letting me know.
Most oil companies and filter companies will perform this service. You usually buy the sample bottle for the price of the test then send it in. This site has a detailed sample report on it. I have never used them but have done samples for hydraulic oil to verify the oil integrity. We used it as a cost saving option on machines with 150 gallons of oil and we have over 60 machines.
https://www.blackstone-labs.com/wp-content/uploads/2019/01/Understanding-Engine-combined.pdf
 
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JakobT

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
Most oil companies and filter companies will perform this service. You usually buy the sample bottle for the price of the test then send it in. This site has a detailed sample report on it. I have never used them but have done samples for hydraulic oil to verify the oil integrity. We used it as a cost saving option on machines with 150 gallons of oil and we have over 60 machines.
https://www.blackstone-labs.com/wp-content/uploads/2019/01/Understanding-Engine-combined.pdf
That’s cool. Thank you for letting me know.
 

JKP

TJ Enthusiast
Joined
Aug 20, 2020
Messages
622
Location
Warner Robins GA
Was it overheating?

Does it still spin over with the starter?

Plugged cats could cause this issue, but they would not result in metal in the oil.

If your mechanic has an oil filter cutter you can check for debris in the oil filter. It's like a heavy duty can opener.

And he can always pull the oil pan.
 
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JakobT

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
Was it overheating?

Does it still spin over with the starter?

Plugged cats could cause this issue, but they would not result in metal in the oil.

If your mechanic has an oil filter cutter you can check for debris in the oil filter. It's like a heavy duty can opener.

And he can always pull the oil pan.
No it wasn’t over heating. Whats weird is it was driving normally and it just started to lose power.

When I try and start it you can tell it wants to start but it just can’t quite get there.

I’ll have to ask about the oil filter cutter.
 

JKP

TJ Enthusiast
Joined
Aug 20, 2020
Messages
622
Location
Warner Robins GA
If you pull the O2 sensor(s) out ABOVE the pre cat(s) on the side of the engine and it starts, your cats are plugged.

Also, was y our oil pressure still good?
 

jeepguy03

TJ Addict
Supporting Member
Joined
Jul 23, 2020
Messages
1,262
Location
Connecticut
+1 on the oil pressure.

Did you hear any knocking? It's very strange for an engine to have a loss of power and suddenly quit without any knocking, oil pressure loss or overheating.

It spinning over and trying to start is a good thing, and means it isn't seized up. You could try testing for spark, and also spray some carburetor cleaner into the intake hose to see if it runs for a second, which would indicate a possible fuel pump problem.
 
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JakobT

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
+1 on the oil pressure.

Did you hear any knocking? It's very strange for an engine to have a loss of power and suddenly quit without any knocking, oil pressure loss or overheating.

It spinning over and trying to start is a good thing, and means it isn't seized up. You could try testing for spark, and also spray some carburetor cleaner into the intake hose to see if it runs for a second, which would indicate a possible fuel pump problem.
I honestly didn’t think to look at the oil pressure while it was happening because I was focusing on trying to get to the side of the highway safely.

I didn’t hear any knocking when it was happening or when trying to start it.

I know one of my friends also said it could be a fuel pump so I’ll have to test that.
 
OP
JakobT

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
Backstory:
I have 2001 Jeep Wrangler Sport and the other day I was on the highway when the engine started to lose power. It wasn’t too fast of first but after less then a minute it was not enough to maintain highway speed and was continuing to decrease. So I pulled off onto the side of the road and it died without me doing anything. Long story short, it wouldn’t start and it was later found that there were metal flakes in the oil. Because of this I’m pretty sure it’ll need a new engine. It has 157k miles but I’m not sure previous owners took very good care of it.

Questions:

Is it better to get a rebuilt/salvaged engine or purchase a new one?

Where are the best places to get a new/used one?

I know it’s broad but approximately how much would it cost to buy the engine plus other parts that are required (not including labor)?

Thank you in advance for anyone to responds to this.
Backstory:
I have 2001 Jeep Wrangler Sport and the other day I was on the highway when the engine started to lose power. It wasn’t too fast of first but after less then a minute it was not enough to maintain highway speed and was continuing to decrease. So I pulled off onto the side of the road and it died without me doing anything. Long story short, it wouldn’t start and it was later found that there were metal flakes in the oil. Because of this I’m pretty sure it’ll need a new engine. It has 157k miles but I’m not sure previous owners took very good care of it.

Questions:

Is it better to get a rebuilt/salvaged engine or purchase a new one?

Where are the best places to get a new/used one?

I know it’s broad but approximately how much would it cost to buy the engine plus other parts that are required (not including labor)?

Thank you in advance for anyone to responds to this.
UPDATE: I got COVID so I couldn’t do anything about the car until now. It did start but it ran horribly. There was a loud screeching along with knocking and you could tell the engine was just overall not running right.
 
OP
JakobT

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
+1 on the oil pressure.

Did you hear any knocking? It's very strange for an engine to have a loss of power and suddenly quit without any knocking, oil pressure loss or overheating.

It spinning over and trying to start is a good thing, and means it isn't seized up. You could try testing for spark, and also spray some carburetor cleaner into the intake hose to see if it runs for a second, which would indicate a possible fuel pump problem.
We got it to turn over today and when it started it ran horribly. There was a knock and a screeching noise but the screeching might have just been a belt.
 
OP
JakobT

JakobT

Member
Joined
Mar 9, 2021
Messages
25
Location
Tucson Arizona
UPDATE: I got COVID so I couldn’t do anything about the car until now. It did start but it ran horribly. There was a loud screeching along with knocking and you could tell the engine was just overall not running right.
UPDATE 2: We cut open the oil filter and there is a lot of metal in it.
 

Yoda

TJ Enthusiast
Joined
May 5, 2021
Messages
171
Location
MA
Are you going to replace/repair the engine or are you going to have someone do it for you?

If you are capable of doing most of the work yourself, I'd send the bare block along with the crank, rods and pistons to a machine shop. As long as things are not beyond repair you can have the block taken care of and the appropriate sized bearings installed. They can polish your crank and make sure everything is good. Have the block decked to make sure its dead flat.

Get a clearwater cylinder head and a stock replacement cam and lifters. As long as you just spun a bearing or flattened some cam lobe and everything checks out okay you'll have a brand new engine for not a whole lot more than getting a used one.