I'm assuming the clatter I hear inside the valve cover of my 73Z is attributable to:

1) soggy springs causing poor contact between the rocker arm and the camshaft, and/or

2) wear and tear on the cam and rocker arms causing improper clearances which leads to slapping.

I know MSA has an entire kit for about $470 to replace the valvetrain with performance parts, but if I just want to leave my engine stock, what's the most likely/affordable way to clean up the clatter in the engine?

Thanx!

Justin

73 240Z

First, have you tried adjusting the valves? Usually an adjustment will clear things up. While your doing that inspect the condition of the lash pads, rocker arms and the cam lobes. Any unusual or excessive wear would indicate a cause to your valvetrain clatter. If the adjustment doesn't clear things up then I would look into replacing parts. BTW do you know how many miles are on the engine?

Could also be caused by the Oiler Spray Bar being cracked at the welds so that oil doesn't get sprayed where it needs to be. (a common issue on old L24 motors) Best way to check is to remove it, clean it up in solvent, and examine it VERY CAREFULLY.

Also could be that the valve lash has not been adjusted correctly, or that the adjustment nuts have gone loose.

First, have you tried adjusting the valves? Usually an adjustment will clear things up. While your doing that inspect the condition of the lash pads, rocker arms and the cam lobes. Any unusual or excessive wear would indicate a cause to your valvetrain clatter. If the adjustment doesn't clear things up then I would look into replacing parts. BTW do you know how many miles are on the engine?

125000 miles on the engine. I've only had the car a month.

It may seem obvious, but check that your exhaust manifold gasket is not leaking. A couple of months ago, I thought I'd damaged a valve after a spirited run down some back roads. There was some serious clattering coming from the front of the engine, and when I investigated further, I found that I'd blown a half inch section of my exhaust manifold gasket away. The exhaust manifold was leaking right underneath the thermostat housing, so it wasn't obious (at least not to me).

Cheers,

Sean

check that your exhaust manifold gasket is not leaking.

Sean

Good point Sean, same thing happened to me. I also thought it was the valvetrain.

I think the $470 MSA kit is a pretty good deal and you can get it "stock" if you want.