10 Guests, 0 Users

Author Topic: Isolating exhaust leak  (Read 1788 times)

0 Members and 1 Guest are viewing this topic.

Offline Flygirl62

  • Pinto Member
  • **
  • Posts: 21
  • FeedBack: +1/-0
  • Another Pinto Driver

  • Total Badges: 2
    Badges: (View All)
    Topic Starter Apple User
Isolating exhaust leak
« 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?

Offline Srt

  • Original Pangra Master Builder
  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1339
  • FeedBack: +100/-0
  • Gender: Male
  • Pinto Stampede ROCKS

  • Total Badges: 10
    Badges: (View All)
    Topic Starter Signature Tenth year Anniversary Poll Voter Linux User Mobile User Windows User 1000 Posts Fifth year Anniversary Photographer
Re: Isolating exhaust leak
« Reply #1 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
the only substitute for cubic inches is BOOST!!!

Offline Pinto5.0

  • Pinto Master
  • *****
  • Posts: 1974
  • FeedBack: +77/-0
  • Gender: Male
  • 80 hatch, 76 Wagon, 72 & 73 Sedans, 71 half hatch

  • Total Badges: 7
    Badges: (View All)
    Topic Starter Signature Poll Voter Mobile User Fifth year Anniversary Windows User 1000 Posts
Re: Isolating exhaust leak
« Reply #2 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.
'73 Sedan (I'll get to it)
'76 Wagon driver
'80 hatch(Restoring to be my son's 1st car)~Callisto
'71 half hatch (bucket list Pinto)~Ghost
'72 sedan 5.0/T5~Lemon Squeeze

Offline 289Wagon

  • Pinto Full Member
  • ***
  • Posts: 234
  • FeedBack: +29/-3
  • Gender: Male

  • Total Badges: 3
    Badges: (View All)
    Topic Starter Signature Fifth year Anniversary
Re: Isolating exhaust leak
« Reply #3 on: July 26, 2013, 08:30:58 AM »
 Does your engine have an A.I.R pump, aka smog pump ?
Still living the dream...In a points & condenser world.

Offline HOSS429

  • Pinto Full Member
  • ***
  • Posts: 203
  • FeedBack: +22/-0
  • old ford guy

  • Total Badges: 4
    Badges: (View All)
    Fifth year Anniversary Topic Starter Poll Voter Windows User
Re: Isolating exhaust leak
« Reply #4 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 !!!!

Offline Flygirl62

  • Pinto Member
  • **
  • Posts: 21
  • FeedBack: +1/-0
  • Another Pinto Driver

  • Total Badges: 2
    Badges: (View All)
    Topic Starter Apple User
Re: Isolating exhaust leak
« Reply #5 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.