Top end knock
#1
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Year: 2000
Model: Cherokee
Engine: 4.0
Top end knock
I have a knock in the top end. Replaced rocker pivots and bridges. Didn't fix it. thinking it might be pushrods. Any other ideas?
#2
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Year: 1998
Model: Cherokee
Engine: 4.0 rebuilt w/ bored TB, banks header, upgraded ignition, 3 row rad, high flow h2o pump, 180* t-stat
collapsed lifter, or a bent pushrod, or bent valve. most likely a collapsed lifter. did you pull the rods when you replaced the rocker pivots/bridges. also rocker pivots have a short break in time where they will make a slight tick until they seat...
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#8
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Year: 1998
Model: Cherokee
Engine: 4.0 rebuilt w/ bored TB, banks header, upgraded ignition, 3 row rad, high flow h2o pump, 180* t-stat
x2....pull the rods and lifters and inspect both, that sounds like a collapsed lifter (loud ticking when cold/at idle is because of low oil pressure and ticking while hot is due to low oil viscosity) meaning your not moving enough oil through the lifter.
#9
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Year: 88
Model: Cherokee
Engine: four.o
i've got the same noise and also replaced pivots,bridges,rocker arms and rods. when you guys say 'lifter'....you mean the tappets at the bottom of the pushrod??if so is it possible to replace them without pulling the head??
#10
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Year: 1998
Model: Cherokee
Engine: 4.0 rebuilt w/ bored TB, banks header, upgraded ignition, 3 row rad, high flow h2o pump, 180* t-stat
yep flat tappet cam uses hydraulic lifters.... and get one of the magnets on a stick and use that. get em to start to pull out then give em a quick yank and they will pop right out.
#12
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
Pull the engine completely apart and dump everything out on the lawn, then put it all back together again. May not fix it, but it will impress the neighbors.
#13
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Year: 1998
Model: Cherokee
Engine: 4.0 rebuilt w/ bored TB, banks header, upgraded ignition, 3 row rad, high flow h2o pump, 180* t-stat
my neighbors just *****ed n moaned about me workin n cussin in the front yard at 2 in the mornin....your neighbors must like you hehe
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Year: 88
Model: Cherokee
Engine: four.o
ok then so what is it?? the motor is a fuel injected 4.0. its in an 88 xj. My first thoughts say that i cant do it otherwise i would have tried while replacing the rest if the parts. has anyone done this or is it just theory??