Hi, I am a professional certified mechanic, with an engineering background, and 35+ years experience. I will do my best to assist you. Also keep in mind I don't know if you are a pro or a novice so we may have to fine tune the answer. Feel free to add any additional info you feel is needed as we go on. Always keep in mind that I am here to help you with any questions.
If it sounds like a lifter, I would consider removing the valve cover and inspect the rocker arms, and look for a bent push rod, which will make the same sound as a sticky lifter. As far as using the seafoam, it will clean, but if the engine is dirty enough inside, it can move debris from harmless areas to areas where it can cause harm. It is just a caution, I know some people swear by it. Over the years I have rebuilt about a dozen engines that had just had seafoam put in them, and one of them was in a vehicle of mine. It is gamble most people get away with it, still it has risks. If it was mine I would inspect the rocker arms, and look for a bent push rod first. If that doesn’t pan out then that is when I would recommend trying seafoam. I have also seen engines clean up sticky lifters with a few rapid oil changes, using good quality oil. Run it about 1000 miles and change the oil a few times like this, is a lot less risky than using seafoam. Give it some thought and If you have any more questions, as always, I am here to help. Good luck with it, have a great day, and Thanks for using Just Answer.
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