1993 Silverado engine knock?

[norcalitrader]

Ok I got a 1993 Chevy Suburban Siverado with the 5.7L 350.

When i first start my truck theres knock sound for like 5 seconds then it stops.

After the truck warms up its ok...

But lately the knocking noise appears on and off at a stop light at idle?

Oil pressure at idle is at 20psi? is that low?

I was told by a friend that it may have something to do with the rockers?
Is there and adjustment I should check on the rockers (like you do valves?)

[broughy84]

your oil pressue is good. if it gets down around 10, be worried. Mine usually runs about 15 at idle. 8 is minimum pressure on a 5.7/5.0/4.3

I don't know about the rockers.

[Thunderbolt]

Your oil pressure is good, But I guarantee the knock you are hearing is a rod bearing. I have seen a few do this and as long as it doesn't get worse or knock steady I would keep driving it and not worry. I have a friend who had the same problem and his startined getting worse eventually. He didn't have money for a new truck or engine so I did a poor mans fix for him. I pulled the engine and pulled the crank out and replaced it with a reground crank, rod and main bearings and new oil pump. It is still running strong after 20,000 miles. The crank and bearings cost $ 140.00, the pump was $30.00 and then the cost of antifreeze and oil so the whole thing cost under $300.00. It may not have been the ideal way to fix it, But it works. As long as the bearing hasn't spun the rods themselves should be ok, But the journals on the crank are out of round. When assembling it everything should be plasti-gauged to check clearances. If I wouldn't of checked my engine would have been toast because they gave me the wrong size bearings.