c2 300hp lifter noise

[John D.]

Just purchased a '67 300hp that had an engine rebuild in 1984. The engine only had 3600 miles put on it from 1984 until the time I purchased the car last week. The prior owner mentioned that a lifter makes noise on an occasional cold start. When I purchased the car I drove it home (approx. 700 miles) in 11 hours without incident. The next morning when I started the car a lifter noise lasted about a minute then was fine. The following morning when I started the car there was no noise. This morning there was again a lifter noise that lasted about a minute then was fine the remainder of the day. Today I also changed the oil using Mobile 1 synthetic.

Any idea what's going on here and what my next step should be? I plan on driving the car at least on a weekly basis. Should I just drive it for a while and see what happens? Thanks for any input.

[Duke W.]

Re: c2 300hp lifter noise

Sounds like a lifter is bleeding down - could be defective or dirty - use HD diesel engine motor oil, API service category CI-4. The much higher detergent concentration might clean it out if it's dirty. Mobil 1 is for powder puffs who drive modern cars that don't nead as much detergent additive as vintage cars! Real men use HD diesel engine oil in their vintage Corvettes.

A noisy lifter at start-up usually won't do any harm, just let the engine idle until it the noise goes away. If it doesn't eventually clear up it should be replaced - especially if it gets worse.

Duke