Just picked up a Chevy G20 for $2700 with 101,000 miles. It’s got some suspension issues, but my main concern is a slight ticking or knocking noise coming from the right side, almost underneath. It only happens at idle or when I’m feathering the throttle, and it goes away when I accelerate. My wife totaled our other car, so I’m trying to get this one in better shape as quickly as possible. I’ve always dreamed of having one of these with wood panels on the outside, so I want to fix it up properly.
If it sat for a while, the noise could be coming from the lifters. You might want to take off the doghouse (the engine cover) to see if you can hear it more clearly. Sometimes these ticks go away with a couple of oil changes. You could also try taking off the valve covers and checking if the valves need adjusting. There’s a lot of potential issues though; we’d need to know exactly where it’s coming from to diagnose better.
@Page
I’m planning to get new tires and an oil change tomorrow, and I’ll give it a good inspection while it’s on the lift. I’ve also heard the oil pump is a weak spot in these engines. Unfortunately, I can’t check the oil pressure or temperature because the gauges aren’t working, so I need to replace those sensors too.
@Destiny
If it’s a lifter or valve train tick, there’s something you can try when you change the oil. Substitute half a quart of ATF (any Dexron should do) for the oil, then change the oil again at half the regular interval, say around 1500 miles. If the tick is still there, repeat the process once more. After that, switch to synthetic oil and a proper filter, and you should see an improvement. The ATF helps clean out any sludge that might be causing issues. I’ve done this with a 250 cu. in. engine in an ‘81 C10 I owned. It had low mileage but had probably gone too long between oil changes before I got it. The oil was black almost immediately after changing it. After doing three oil changes with the ATF method, the oil was coming out nearly clean, and the engine ran noticeably smoother and started easier, especially in winter.
@Zander
Or you could use Seafoam with Valvoline Restore and Protect. I’ve heard good things about that too.
Jesse said:
@Zander
Or you could use Seafoam with Valvoline Restore and Protect. I’ve heard good things about that too.
ATF is far less harsh than Seafoam. I wouldn’t use something as aggressive as Seafoam in an older engine, especially if it’s got some miles on it. ATF cleans more gradually and is a safer option.