Man I got a problem. 97 TJ with 190K. Couple of weeks ago I heard a snap followed by rough running. When I opened up the valve cover one of the bolts that holds down the rocker arm had broken off just below the head. I replaced the whole assembly pushrods and all, one rod had bent slightly. Everything was going great until today when I heard the same sound. Opened up again to find the same thing had happened to the adjacent cylinder. Anyone know what is causing this? Thanks for the help!
Broken Rocker Arm Bolts!
- Thread starter Forceof1
- Start date
I think I would inspect the valve stems for signs of wear, the rocker arms signs of heat and galling, and might not be a bad idea to remove the rocker arm and pushrod, inspect the lifters and the lobes on the camshaft for signs of wear or damage.
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Thank you for your help. I've removed the broken bolt and rocker but the one next to it is situated at an odd angle. I don't know if this indicates anything or not. I get a bad feeling I'm headed for a rebuild..........
That doesn’t look good from what I can judge in that picture.
Remove the push rods from two other valves, look down in the holes and compare the appearance of the lifters to see if the lifter appears damaged. There is a chance lifter collapsed or there is a bent pushrod.
I suspect there may be a problem with either the pushrod, lifter(s) or cam lobe(s) for those valves.
Remove the push rods from two other valves, look down in the holes and compare the appearance of the lifters to see if the lifter appears damaged. There is a chance lifter collapsed or there is a bent pushrod.
I suspect there may be a problem with either the pushrod, lifter(s) or cam lobe(s) for those valves.
Will do. Also wondering if my camshaft is in bad shape. I'll get a visual on things tomorrow. Thanks for your help.
Valve timing due to worn/jumped timing chain? (valve kisses piston, weakest link breaks).
edit: according to Google the neither 4.0 or the 2.5 are interference engines so my speculation doesn't seem too likely although I wonder if the chain was real loose if it could still happen? Or if over-revved by early downshifting?
For it to happen twice on 2 different cyls there has to be a common denominator. Something in the oil causing lifters to stick?
edit: according to Google the neither 4.0 or the 2.5 are interference engines so my speculation doesn't seem too likely although I wonder if the chain was real loose if it could still happen? Or if over-revved by early downshifting?
For it to happen twice on 2 different cyls there has to be a common denominator. Something in the oil causing lifters to stick?
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