Weird tapping when accelerating, exhaust leak?

Engine, ignition, fuel, cooling, exhaust

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crazzmc
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Weird tapping when accelerating, exhaust leak?

Post by crazzmc »

Got a weird tapping sound today from the motor today. Never heard it before haven't driven much recently either. Only when accelerating, idles fine. I did some quick googling people saying it could be en exhaust leak? At first I thought it was my air cleaner cause I got it spaced up because of my HEI but I held it and it was still happening. It could be from the driver side but I may be wrong.

Oil pressure ~50
Temp ~ 185
Idles ~950-1100 (My truck doesn't really like idling lower)
Oil changed less than 100 miles ago


2 videos posted below:

https://youtu.be/cnGjbOvKFIk

https://youtu.be/kePryC5m5sI

Thanks guys!

-Raj
Figuring out this whole restoring process with my 68' F100.
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farmallmta
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Re: Weird tapping when accelerating, exhaust leak?

Post by farmallmta »

Sound isn't all that great on my computer, but it doesn't sound like an exhaust leak. It sounds like a wearing-out idler pulley, loose harmonic balancer, loose motor mount or engine perch, or loose fan component. Also perhaps a wearing out alternator or even an about-to-fail belt.

Hope this helps. Let us know what you find.
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sparky72
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Re: Weird tapping when accelerating, exhaust leak?

Post by sparky72 »

What are your engine specs and what's your timing set at? 1000rpm idle is pretty high unless you have a fairly large cam or pretty advanced timing (or a vacuum leak).
Taylor
1972 F250 Ranger XLT 2wd / 8100 GVW / 390 / T18 / 3.73 D60
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beejaytx225
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Re: Weird tapping when accelerating, exhaust leak?

Post by beejaytx225 »

It's it possible that's it's poor gas pinging? Sounds like something is wobbling bad maybe. Sounds rough :cry:
1968 F-100 Ranger LB
360 w/C6
Peacock Blue
Family nicknamed her "Bethany"
Central Texas
Past Ford's: 1994 Ranger, 2008 Ranger, 1991 Ranger, 1985 Mustang, 1968 SB Custom Cab F100, 1998 Explorer.
Current Ford's: 2011 Ranger, 2006 Expedition, and of course Bethany :)
Mach428
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Re: Weird tapping when accelerating, exhaust leak?

Post by Mach428 »

Remove all the belts and see if the sound disappears. If it does, add one belt at a time and test to determine if it's any of the suggestions. If it doesn't, it rrules out bolt-on components.
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My427stang
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Re: Weird tapping when accelerating, exhaust leak?

Post by My427stang »

SBFs are known for breaking piston skirts if old motor and you revved it to hit the ridge

Also sounds like potential wrist pin

However, given that we are listening over Youtube, I would take a long stick put it up against fuel pump see if you feel it with your ear against the stick

If not, pull valve covers, make sure you dn't have anything broken

Check converter nuts and see if you can see flex plate if automatic

I think you will be going inside if not a fuel pump though
71 F-100 SB 4x4, 461 FE, Edelbrock Pro-flo 4, 4 speed, 4 inch softride lift, all poly bushings, integral PS, most mods installed since the 80's
70 Mustang Sportsroof 489 FE, EFI, TKO-600 5 speed, 4.11s
Engine building by-appointment only--30+ years, specializing in strong street pump gas FEs
crazzmc
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Re: Weird tapping when accelerating, exhaust leak?

Post by crazzmc »

My427stang wrote:SBFs are known for breaking piston skirts if old motor and you revved it to hit the ridge

Also sounds like potential wrist pin

However, given that we are listening over Youtube, I would take a long stick put it up against fuel pump see if you feel it with your ear against the stick

If not, pull valve covers, make sure you dn't have anything broken

Check converter nuts and see if you can see flex plate if automatic

I think you will be going inside if not a fuel pump though
I just took apart the truck so I'm about to start digging in this weekend. Should be interesting to see what I find. I haven't read torque specs on a lot of stuff yet but my engine mount nuts and my bolts from my bell housing were finger tight. I did have a decent amount of vibration as well (air filter would be going crazy) when my motor was running.

But I am at this state so pretty excited first time ever:

Image
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Figuring out this whole restoring process with my 68' F100.
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