If your sure it'* a lifter causing it, you can try to seafoam in the oil, then change the oil again. If that don't clear the lifter, and you are sure it is a lifter, it'* not that hard to change them out. I don't know every detail about your engine, but for the most part it'* remove the valve covers, remove the upper and lower intake manifolds. Remove the rockers and push rods. Remove the lifter retainers, two bolts each side. Then use a magnet to lift the lifters out. Reverse the order when putting it back together. You will need new rocker bolts, you can't reuse the stock ones. Only special tool you will need is a inch pound torque wrench.
SAVING THE WORLD ONE BONNEVILLE AT A TIME
1997,1998,2000,2005 year confused Bonneville SSExi. Stock? ish.
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