1977 Mark V – Tracking Down A Noise

Hi Bill,

Thanks for all you do for us Lincoln owners!

I have an interesting question to ask…one that I have not seen on your forum.

Today, I took my 1977 Lincoln Mark V with a 460 four-barrel to a local transmission shop to swap out a leaking transmission gasket (minor leak in the area of the bell housing). About three days before (Saturday) I brought it to them, my car began making a loud noise that sounds EXACTLY like a driver’s side exhaust manifold leak, or even crack. It’s loud enough that you can hear it when the car is driving by you and gets louder on revving or acceleration. I asked the mechanic doing the transmission work to diagnose it and he says he does not believe the sound is coming from the manifold. They believe it is coming somewhere from the front of the intake manifold area and they do not want to take on the job to further diagnose or repair.

The only other clue I have for you is that there was a little bit of ticking prior to the noise becoming Much louder…the kind of ticking one would associate with a small manifold gasket leak, or noise from inside the valve cover.

The car has 47,000 miles. Is there anything involving the intake manifold, which, in your experience would cause a sound exactly like a cracked or leaking exhaust manifold? It is almost certainly coming from the drivers side front of the vehicle and is louder forward of the wheel when you’re on the ground than behind the wheel when you’re on the ground.

Thank you again. Any insight would be much appreciated.

V/R,

-Andy

Southampton, MA

Hi Andy –

The only advice that I can think of without being there and hearing the actual leak is for you to visit a well-known local muffler/exhaust shop. One of their techs can use their stethoscope to pinpoint the actual leakage and then possibly repair it. This is where we would probably begin the diagnosis at Lincoln Land. We will have easy access to any parts for you that may be needed for the repair etc. Good luck!

Sincerely,

Bill