Engine knock: Lifters?

Kevin E

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Wharton, TX
98 Sport 4.0. Started making noise this morning on the way to work. Any help is appreciated.
 
Anybody? I know I haven't been on in a while, but to be shunned is having a negative impact:D
 
Hard to say, it seems to be coming from the top of the engine, its more of a ticking than a knock sound to me... it almost sounds like a small exhaust leak.
If the noise is worse on the manifold side i would start checking manifold bolts for anything loose.
 
Does it quiet down when it warms up ?
No. However the knocking will go faster or slower with RPMs. I've read it could be lifters, loose bolts for lifters, piston skirt crack and other miscellaneous responses. Thought I would ask the experts and try not to guess. I haven't taken anything apart yet or drained oil. Thanks
 
Th
Hard to say, it seems to be coming from the top of the engine, its more of a ticking than a knock sound to me... it almost sounds like a small exhaust leak.
If the noise is worse on the manifold side i would start checking manifold bolts for anything loose.
Thanks for the reply. Yes it does seem louder on that side. I will check the bolts and look on manifold side.
 
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Hard to say, it seems to be coming from the top of the engine, its more of a ticking than a knock sound to me... it almost sounds like a small exhaust leak.
If the noise is worse on the manifold side i would start checking manifold bolts for anything loose.

That's what I was getting at, exhaust leak or cracked manifold.
 
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An old trick most know, use a stethoscope or long screwdriver to pinpoint where the sound is coming from. This video explains it best. You can at least get an idea where the noise is coming from rather guessing from using your eyeballs.
It is also useful to look "smart" when you look at a car and use that to negotiate the selling price.
 
UPDATE
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Wow, the piston skirt is missing! How do you think this happened?

You know what time it is now, right? STROKER time!
 
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Wow, the piston skirt is missing! How do you think this happened?

You know what time it is now, right? STROKER time!
If I had the money I would in a heart beat. I don't know how it happened. I do regular maintenance since I bought her 3 years ago. 145,000 miles. Heard the noise last Saturday on my way in to work. I'm getting all pistons replaced and the block re bored so I should be good. The redt of the engine looks good. If and when the engine is replaced it will be a V8 swap though. I'm like you and overbuild!
 
If I had the money I would in a heart beat. I don't know how it happened. I do regular maintenance since I bought her 3 years ago. 145,000 miles. Heard the noise last Saturday on my way in to work. I'm getting all pistons replaced and the block re bored so I should be good. The redt of the engine looks good. If and when the engine is replaced it will be a V8 swap though. I'm like you and overbuild!

How much are you having to pay for all of that?

Sounds like a total fluke, since this definitely isn't common with the 4.0! I guess the good news is that these engines are so common that parts aren't expensive for them!
 
Finally got my Jeep back from the shop. Man what a difference!
Sounds more quiet and runs better. New clutch also while they had it.
 
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Finally got my Jeep back from the shop. Man what a difference!
Sounds more quiet and runs better. New clutch also while they had it.

Hey Kevin - thanks for the post. My '99 is making identical sound. Curious if you experienced any loss of power or oil burning. I haven't seen those symptoms yet.

Also, curious what kind of cost I should plan on. Can you give an idea of the range you paid?

-Rob
 
No I didn't have any oil nurning or anything. It was fine and then started knocking on my way to work one day.
All pistons replaced and and lower end rebuilt with new clutch and a few other things was $2300
The top end is still good condition.
 
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