loose rocker arm on reassembly
#1
Junior Member
Thread Starter
Join Date: Mar 2013
Posts: 48
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
loose rocker arm on reassembly
Pulled the valve cover for what was initially a head gasket job.
pushrod #5 (back to front) was dislodged from rocker head
while replacing the rocker arms and pushrods i notice that rocker head #5 sits loosely on the spring/pushrod
an eye check doesn't detect a low-sitting spring, bent rod, or a screwed rocker arm
would this mean the lifter is bad, or possibly gunked up?
are there any treatments that can be done without pulling the lifters?
pushrod #5 (back to front) was dislodged from rocker head
while replacing the rocker arms and pushrods i notice that rocker head #5 sits loosely on the spring/pushrod
an eye check doesn't detect a low-sitting spring, bent rod, or a screwed rocker arm
would this mean the lifter is bad, or possibly gunked up?
are there any treatments that can be done without pulling the lifters?
#2
CF Veteran
Join Date: Dec 2010
Location: Finger Lakes Region NY
Posts: 1,234
Likes: 0
Received 1 Like
on
1 Post
Year: 1990
Model: Cherokee
Engine: 4.o
Not quit sure i follow you. got a pic?
Cheap lifter fix (some times works, some times doesn't)...idle some Seafoam or ATF in the oil. Or any really good detergent to break up sludge n gunk. then change oil
Cheap lifter fix (some times works, some times doesn't)...idle some Seafoam or ATF in the oil. Or any really good detergent to break up sludge n gunk. then change oil
#3
CF Veteran
Join Date: Aug 2010
Location: Canton, MI
Posts: 8,357
Likes: 0
Received 82 Likes
on
67 Posts
Year: 1999
Model: Cherokee
Engine: 4.0
Pulled the valve cover for what was initially a head gasket job.
pushrod #5 (back to front) was dislodged from rocker head
while replacing the rocker arms and pushrods i notice that rocker head #5 sits loosely on the spring/pushrod
an eye check doesn't detect a low-sitting spring, bent rod, or a screwed rocker arm
would this mean the lifter is bad, or possibly gunked up?
are there any treatments that can be done without pulling the lifters?
pushrod #5 (back to front) was dislodged from rocker head
while replacing the rocker arms and pushrods i notice that rocker head #5 sits loosely on the spring/pushrod
an eye check doesn't detect a low-sitting spring, bent rod, or a screwed rocker arm
would this mean the lifter is bad, or possibly gunked up?
are there any treatments that can be done without pulling the lifters?
Do you have #5 piston at top dead center, compression stroke when you observe this?
You should remove the applicable rocker and rod and look down to the top of the tappet using a bright flashlight. See if the pushrod seat retaining snap ring has come loose or the seat is damaged, or both. Compare the postion of the seat in the tappet to another known good tappet as a reference to see if the seat is at the top of its travel. Normal lash/preload travel of the seat is about .040-.060".
If the pushrod seat/retaining ring are intact have a helper rotate the crankshaft at the crank vibration damper while you look at the tappet from above and see if the tappet moves freely. Place and hold pressure on a pushrod on the tappet while the crank is being rotated and see if you can feel the tappet moving up and down (compare to another tappet as a reference). Rotate the crankshaft two complete revolutions.
If the tappet up and down travel is not the same as a known good tappet, the cam lobe for that tappet may be worn.
If the tappet movement seems okay, and the pushrod seat and its retaining ring are okay, but the pushrod seat seems to be stuck about .060" down from the top you may want to try to free it up by pouring some Marvel Mystery Oil on top of the tappet and apply a pumping action to a pushrod on the pushrod seat to see if it will free up. If it won't it looks like the seat is stuck in position or damage to the internals of the tappet has occurred.
See cutaway of a hydraulic tappet (lifter) below.
#5
Junior Member
Thread Starter
Join Date: Mar 2013
Posts: 48
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
yea geeky i measured it roughly with a ruler and it was about an 1/8" inch.
my writeup posted on jeep forums:
found a tip from cherokee forums, i poured half a bottle of seafoam down rod-hole #5, then torqued the rocker heads and then finished buttoning her up (not before having to reposition the f$%^ing intake manifold - redlined on first startup). It ran with a loud loud knock for about 20 minutes and then it went away, had to be careful not to put it over 2.5krpm or else the sound got worse. so fortunately for me my lifter was simply just gunked up, the same gunk that threw rod #5 in the first place. Now just to get an oil change tomorrow and beg for another 100k miles
my writeup posted on jeep forums:
found a tip from cherokee forums, i poured half a bottle of seafoam down rod-hole #5, then torqued the rocker heads and then finished buttoning her up (not before having to reposition the f$%^ing intake manifold - redlined on first startup). It ran with a loud loud knock for about 20 minutes and then it went away, had to be careful not to put it over 2.5krpm or else the sound got worse. so fortunately for me my lifter was simply just gunked up, the same gunk that threw rod #5 in the first place. Now just to get an oil change tomorrow and beg for another 100k miles
Thread
Thread Starter
Forum
Replies
Last Post
407rotorhead
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
3
06-07-2023 02:44 AM
toasterknight
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
33
05-21-2016 07:03 AM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)