PINTO CAR CLUB of AMERICA

Welcome to FordPinto.com, The home of the PCCA => General Help- Ask the Experts... => Topic started by: Flygirl62 on July 23, 2013, 03:02:07 AM

Title: Isolating exhaust leak
Post by: Flygirl62 on July 23, 2013, 03:02:07 AM
2000cc, '73 Runabout. Car's running well, but what sounds like an exhaust leak is bugging me. I've been reading about other instances of this, but thought I'd ask.

It's a 'pht-pht-pht' sound that changes with RPM, most noticeable from 2000-3000 or so RPM in second and third gear, when the throttle is past 1/2.

Sounds like it's coming from the front of the car, but where I'm not sure. My guess is the manifold/head area, based on the sound, but wondering if the doughnut between the manifold and downtube is the problem?

How can I begin to isolate it?

Any common areas I might check?

The 2000cc doesn't use an exhaust manifold gasket, does it? If the manifold is warped or something, can a gasket be added?

And if it's in the doughnut area, do any of those exhaust wraps or JB Weld type products work?
Title: Re: Isolating exhaust leak
Post by: Srt on July 24, 2013, 06:25:49 PM
no they don't use a gasket but that doesn't mean a leak can't occur. the donut area usually wont emit the type of sound that you describe. use a length of heater hose and hold one end to your ear and move the other around all areas of the system.
it should help you pinpoint the problem area
Title: Re: Isolating exhaust leak
Post by: Pinto5.0 on July 25, 2013, 01:32:31 AM
Usually you can feel a leak with your hand but do it when the engines cold. You wont have much time before it gets hot to the touch so be quick. Check the manifold to head, the donut & the pipes.
Title: Re: Isolating exhaust leak
Post by: 289Wagon on July 26, 2013, 08:30:58 AM
 Does your engine have an A.I.R pump, aka smog pump ?
Title: Re: Isolating exhaust leak
Post by: HOSS429 on July 26, 2013, 09:06:47 AM
"pht-pht-pht "  that`s also the sound an angry cat makes  :) .. mite want to look for that ....... HA !!!!
Title: Re: Isolating exhaust leak
Post by: Flygirl62 on July 26, 2013, 10:51:15 PM
Thanks, guys. I found it using y'all's suggestions. It was around the donut, 40 years old and I suppose it needed to be replaced. So that's what I did, and it worked!

I also didn't think it'd make that kind of sound, I suspected the exhaust manifold was leaking from one cylinder. But now it's nice and quiet; that little 2 liter sounds like its thrummy little self again.