motor knock
11-20-2011, 08:47 AM
#1
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motor knock
When I start my jeep in the morning there is a knock sound coming from the lower end of the motor(I think). I also had the same problem with my last XJ. But the knock goes away when u either have it in gear or when u rev it up. Any ideas?
11-20-2011, 05:13 PM
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
11-20-2011, 05:20 PM
#5
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My 95 we got cheap because the torque converter bolts was loose.
IF it knocks and goes away shortly after starting, its typically a main knock.
Only does it till the oil pressure comes up.
IF it knocks and goes away shortly after starting, its typically a main knock.
Only does it till the oil pressure comes up.
11-21-2011, 04:48 AM
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Also you haven't acknowledged a very good suggestion that this Jeep probably has loose torque converter to flexplate bolts. You, or someone else capable of doing this, need to check them or you'll be paying for a flexplate in the future. Not cheap.
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11-21-2011, 07:33 AM
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Year: 1997
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Engine: 4.0, comp cam, 99 intake, apn header, neon injectors, Thunderbolt 2.5" High Flow Cat
if it was a rod bearing it would get louder when you had a load on it. if it's getting quieter with load, I'm betting flexplate or valvetrain. You can get a stethoscope for like 10-15 bucks at autozone.
11-21-2011, 10:36 AM
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Year: 1997
Model: Cherokee
Engine: 4.0 Ltr AMC
Originally Posted by Donnie_K
if it was a rod bearing it would get louder when you had a load on it. if it's getting quieter with load, I'm betting flexplate or valvetrain. You can get a stethoscope for like 10-15 bucks at autozone.
11-21-2011, 11:00 AM
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Year: 1999
Model: Cherokee
Engine: 4.0 High Output
If its constant throughout the rev range id look at rod bearings if I were you...
11-21-2011, 11:28 AM
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Year: 1997
Model: Cherokee
Engine: 4.0 Ltr AMC
Originally Posted by XxXJ99xX
If you replace the bearings yourself not much. Alot of work to do though, How loud is it and does it get progessively worse when you rev it?
If its constant throughout the rev range id look at rod bearings if I were you...
11-21-2011, 11:30 AM
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Year: 1997
Model: Cherokee
Engine: 4.0 Ltr AMC
Sounds like something loose upon ignition, then goes away until throttling. Doesn't seem to do it all when climbing the higher gear.
11-21-2011, 11:57 AM
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Year: 1997
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Engine: 4.0, comp cam, 99 intake, apn header, neon injectors, Thunderbolt 2.5" High Flow Cat
if you've got a bearing going bad to the point you can hear it, it's time for a complete rebuild or replacement of that engine.
11-21-2011, 12:26 PM
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Year: 1997
Model: Cherokee
Engine: 4.0 Ltr AMC
Originally Posted by Donnie_K
if you've got a bearing going bad to the point you can hear it, it's time for a complete rebuild or replacement of that engine.
