[tek88]

after my truck sits for over 10 hrs it makes a weird hollow metallic sound for 40 seconds than goes away. the motor is a 88 4.3 and has about 3500 miles on it. i know its not a rod knock. was thinking maybe a weak lifter. any suggestions

thanx

 

[tom3]

My new Blazer is doing this too. Going to try a different brand and weight of oil, think the 5w30 dealer oil is not doing the job. Maybe with your fresh rebuild you need to readjust the valves.

 

[rablair]

Maybe it's piston slap. It can sound like a lifter or a valve tap and often goes away once the pistons warm up a little.

 

[BlazerLT]

Try a better oil filter like the AC Delco.

It has a a better antidrain back valve to keep the oil up in the top end of your engine.

This has been know to be one of the causes of the tapping.

 

[tek88]

thanx for the help every1 im gonna check it out later 2day.