broken push rod
#1
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Year: 1998
Model: Cherokee
Engine: 4.0l
broken push rod
So i took the valve cover off yesterday only to find one of the push rods sitting down, like it had fallen off the lifter. So i pull it out and it is bent and broken. !!!!!! Its a 98 with the 4.0. I know to replace lifters, which Im 95% sure is completely stuck and has been causing my misfire for months now, I have to pull the head. That wouldnt be a problem and a pain if i didnt have the head off a month ago to replace the gasket. So, a few questions:
Will the broken piece of the pushrod make its way to the oil pan?
Any quick fixes for a stuck lifter that doesnt include removing the head?
Will the broken piece of the pushrod make its way to the oil pan?
Any quick fixes for a stuck lifter that doesnt include removing the head?
#2
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You had the head off and didn't have it reworked?
Are you sure you re-installed the push rods correctly?
How large is the piece that's broken?
Are you sure you re-installed the push rods correctly?
How large is the piece that's broken?
#3
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Year: 1998
Model: Cherokee
Engine: 4.0l
When the head was off, I had it cleaned and resurfaced. The shop said it was fine. Im starting to think that i may have put the one rod back not quite in the right spot and slight vibrations made it fall. As far as the piece that broke, small. Havent taken out a second one to compare.
#4
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Year: 1998
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The jeep has been running the same way as it did before i took the head off, so clearly the misfire that I've been getting wasnt caused by this pushrod issue. Ive narrowed it to a bad lifter, or a valve issue.
#6
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not anything different than it had been doing. I havent started it since i noticed the rod being broken but I put about 3-400 miles on it since replacing the head gasket.
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Wierd.
I can understand the bent part if the lifter collapased and caused all kinds of clearance, but I don't see what could break it into pieces. I guess tear it apart & have a look.
I can understand the bent part if the lifter collapased and caused all kinds of clearance, but I don't see what could break it into pieces. I guess tear it apart & have a look.
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#8
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it kind of looks like it somehow missed the lifter and was sitting beside it. So when the cam rotated and the lifter tried to do its job it was pressing up on the side of the rod and eventually snapped it. There is a spot on the bend of the rod that clearly has been worn, down to bare metal.
#9
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Since it was before and after you had the head off and they checked the valves - they would have seen a sticky valve when they resurfaced it.
It's probably been a sticky lifter all along. Probably not stuck, just slow to return. They get dirty inside.
You might be able to save it - but it's a long shot.
Try dribbling laquer thinner down another pushrod - get it in the lifter. Keep doing it over several days. The laquer thinner may dissolve the carbon chunk inside.
Use leverage - push the lifter down, collapsing it - .040" or so,
quckly let it up - the lifter should follow as fast as you can let it up.
If not, replace it.
The broken piece - try a magnet through other holes - maybe.
If it goes down below it will PROBABLY drop safely in the pan. If it doesn't - you'll know it!
Change the oil - use he mgnet to fish around the oil pan inside.
It's probably been a sticky lifter all along. Probably not stuck, just slow to return. They get dirty inside.
You might be able to save it - but it's a long shot.
Try dribbling laquer thinner down another pushrod - get it in the lifter. Keep doing it over several days. The laquer thinner may dissolve the carbon chunk inside.
Use leverage - push the lifter down, collapsing it - .040" or so,
quckly let it up - the lifter should follow as fast as you can let it up.
If not, replace it.
The broken piece - try a magnet through other holes - maybe.
If it goes down below it will PROBABLY drop safely in the pan. If it doesn't - you'll know it!
Change the oil - use he mgnet to fish around the oil pan inside.
#10
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Year: 1998
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Just drop some down the hole on the pushrod? I might give that a try. Id like to try anything and everthing thats cheap/free before pulling the head again.
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