In my quest to identify a funny noice my Rangie 4.6 makes, I got out and bought myself an autmotive stetoscope.

Bottom line is, I listened at the valve covers, exhaust manifold bolts, cats, oil pan, oil pan bolts in the block, flange between Y-pipe, and manifolds and a few other places. All i hear is a purring engine. No grinding, clicking or whining. Nothing other than the cylinders firing nicely.

But the truck makes some audible clicking noices to the naked ear. More when warm, but always something. It is less than a leaking manifold gasket. (Newly changed, no difference. Does NOT sound like Tobbjo's leaking 3.9). The sound does not seem to be connected to a particual cylinder, as pulling plug wires one by one doesn't really change it.

It comes more from under the truck than under the hood. I'm suspecting a pinhole or crack in a weld on the factory stainless headers, or something similar.

An experienced tech has listened and said it's not a cam lobe or rocker on it's way out.

Time to forget the whole thing and assume the engine is healthy? Or have I overseen something here?

Factory stainless headers? I thought all the Rover V8s had cast manifolds. What year is your truck?

Doug W.

Factory stainless headers? I thought all the Rover V8s had cast manifolds. What year is your truck?

Doug W.

'96 4.6 HSE. Different frame from RRC, I think they chose the headers to make things fit.

Anyone know if these are bolt on to all rover/buick 215 heads? Tighter clearance means they'll get around the 110 frame?

If yes to above, heading for the salvage yard to get me some.

Doug W.

Ohh, this is a gross hi-jack. Sorry Wilsby. I had a tick like that and turned out to be a tiny weldable crack in the factory Y pipe at the manifold.

Doug W.

Ohh, this is a gross hi-jack. Sorry Wilsby. I had a tick like that and turned out to be a tiny weldable crack in the factory Y pipe at the manifold.

Doug W.

Don't mind a little hi-jack as long as I get some sound advice in the process. How did you locate the crack, just by listening?

I can live with the tick, but want to rule out major mechanical failures in the making, since I use this rig for towing long distances.

People mix and match blocks and heads, which leads me to believe the headers would fit, but it is not a guarantee of course.

Just took it to a good muffler shop and they found it. Welded it back together that day. But it was pretty clear to me that the noise was coming from the passenger side of the engine, and it was clearly louder when I was under the truck. There is a heat shield on mine that kept me from inspecting the joint myself.

DW