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Hi Tom, my name isXXXXX from the valve cover can be caused by a bad lifter but it can also be caused by a bad rocker arm or a bad camshaft. If the ticking is a bad camshaft it's going to cost a lot for the repair. Before you pull the trigger I would take the car to a mechanic and have him remove the valve covers to inspect the cam and rockers and lifters. This would also be a good opportunity to inspect the timing chain guide rails. Broken guide rails are a common problem on the SL and can cause the timing chain to jump time and damage the motor. It would also be a good idea to have the complete car inspected for overall condition and needed repairs. There may be problems that you are unaware of that would turn up during a pre purchase inspection.
Please let me know if you have any questions.
only 75,000 mi ticking is slight and rear passenger side. wouldn't the cam or rocker have a mor solid nock
I've heard them tick with both problems and they don't sound much different. When the cam wears the round lobe gets a little squared off and ticks as it passes the rocker arm. The surface of the rocker arm can also wear.
Additionally, there is a cam oil line that oils the rocker arms. I've seen the oil line plug up and starve one of the lifters for oil. I've also seen the oil line retainers break and cause lack of oil pressure in the oil line.
I will be taking this to my mechanic tomorrow.
Very good. I think it's best to have the inspection before you make your decision.
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Thank you for your opinion.
You're quite welcome.