Jeep Cj rocker arm help -
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post #1 of 3 Old 09-14-2021, 06:30 PM Thread Starter
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Jeep Cj rocker arm help

Hey I have a 77 CJ with the 4.2, I recently started getting a horribly loud ticking/ rattling from the engine at any deceleration while in gear. So I pulled the valve cover and found several rocker arms had a decent bit of play. , I went ahead and ordered replacements for all of them and got them in today. When I got them torqued to 21 ft/lbs which is what my Chilton's guide said, the new ones had more play than the old ones. Anyone know what I did wrong? The rocker arm replacement I got was the MELLING MRK5412 which is recommended for my year and engine.

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post #2 of 3 Old Yesterday, 10:48 AM
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The play is likely from the lifters going bad. Did you start the engine before checking the free play? If not, the oil drains out of the lifter and you will have excessive clearance. Need to run the engine a short amount of time to 'pump up' the lifters. Also did you check your pushrods for straightness when you had the rockers removed?

80 CJ-5, 74 CJ-6, 56 CJ-5
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post #3 of 3 Old Today, 09:20 AM Thread Starter
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No I haven't run it yet with the new rockers. I did find that when I first torqued the bolts down they seem to be pretty solid but after a few minutes it was like they weren't tightened all. I did pull all the push rods and check them over and put them back in their original holes and they all seemed fine. I'm fairly certain the old rockers were just pretty worn. the engine itself was apparently rebuilt about 50,000 miles before I got it and I've only put about 20,000 on it. Would lifters wear out that quick or was the person wrong about when they rebuilt it. I'll crank it when I get off work today to see if that will fix it. Thanks for the help.
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