1964 Chevy Truck Motor Problem

[Reddog123]

My 64' Chevy truck -slant 6 motor started making a knocking noise when it started up. It is a noise I have never heard before. It sounds like metal on metal. Does anyone have an idea what this could be, before I start tearing down the motor?

[MacAttack]

Tinny sound? Banging sound. Low-Thumping sound?

[Oregoon]

If you have a slant six, you have a Dodge. That's a problem.

Seriously though, I imagine you have an inline-six, and metal on metal noises can be anything from a loose fan to a spun rod-bearing. Is it clunky, or scrapey sounding? Does it go away when you give it fuel, or get louder? Are there metal shavings in your oil, or on your drain-plug? Is there water in the oil, or vice-versa? Does anything feel loose?

Take a stethoscope (with a rag wrapped around it), or a piece of rubber tubing, and listen to different places around the motor, to see if you can determine where it's coming from. That's often a good start.

[5264chevytrucks]

I had my 64 crack piston 6 and 4 and the noise I heard was pieces bouncing around. Of course, I had smoke coming out the tail pipe too.

[Chevy Fleetside]

Grab the fan and see if it wiggles. If so the bearings in your pump are bad.

[MacAttack]

If it's an automatic transmission - check the flex plate. Sometimes, if the fan belt's be over-tightened you can crack the long-nose pulley too. If you hit something on the road - you might want to check the transmission cover.

[Muleman100]

I have never seen a slant six in a Chevy, only in Dodges. Yank it out and get a good 250 or 292 inline Chevy six.

[Oregoon]

I've seen a slant-six swapped into an International, a Ford truck with a Duetz air-cooled diesel, a Willy's with a Toyota motor, and a Scout with a Pinto 4-pot... And I'd like to build a '60-'66 with an Isuzu Diesel.

Just sayin'.