post #1 of Old 05-06-2012, 10:31 AM Thread Starter
sevenscrew
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4.0 tapping matching rpms

there's a tapping sound from near the center of the intake manifold /engine. has a bad valve cover gasket leak. 196k

it matches the rpms and is more noticable since I put in a new muffler and tailpipe.


any ideas ?


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post #2 of Old 05-06-2012, 10:57 AM
dusterdude
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Lifter?
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post #3 of Old 05-06-2012, 11:13 AM Thread Starter
sevenscrew
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can I easily access/fix a lifter with the cover off

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post #4 of Old 05-06-2012, 11:20 AM Thread Starter
sevenscrew
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can I easily access/fix a lifter with the cover off

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post #5 of Old 05-06-2012, 11:23 AM
JasonStebbins
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Sounds maybe like a lifter, is the oil up to level? Could be a cracked manifold as well.

Yes. There are like 12-14 bolts that hold the cover on. The hardest part is getting around all the throttle/transmission cables.

I would recommend changing the front and rear PCV valves while you have the cover off.

Poop
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post #6 of Old 05-06-2012, 01:40 PM Thread Starter
sevenscrew
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oil needed 4 quarts when we picked it up for 450 bucks. so it was almost empty for idk how long probably arounda month. Once i get the cover off, if its a lifter, can i change it with just a torque wrench? and is the part a dealer item then?

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post #7 of Old 05-06-2012, 02:53 PM
Oldfrog
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Before you begin tearing it down, try pouring a little marvel mystery oil in the crankcase. Drive it for a day, then change the oil again. See if it stops.
That said......sometimes even a brand new 4.0 will sound a bit like a diesel engine at times. Both of mine have, every once in a while and I bought them both new.

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post #8 of Old 05-06-2012, 03:12 PM Thread Starter
sevenscrew
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okay thanks will try that

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post #9 of Old 05-06-2012, 03:30 PM
JasonStebbins
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If it was four quarts low for an extended period of time I wouldn't invest too much into the motor. Is it a tap or a knock? My tap goes away with the above suggested Marvel Mystery Oil but if it continues while warm with RPM it sounds more like a rod.

Poop
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post #10 of Old 05-06-2012, 05:54 PM Thread Starter
sevenscrew
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when i get off the valve cover for the gasket change, is there anything i can look for to find the tap easily? or is it very hard to find the bend. if its a rod i can change that easily by taking the bolt out of the rocker arm, then just remove the rod and put a new one in right?

its a tapping ish almost a click sound. you dont really feel it through the floor or pedal or anything so i wouldnt say a knock. ill try getting a vid up tomo.

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post #11 of Old 05-06-2012, 06:28 PM Thread Starter
sevenscrew
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not sure if this is related, but the oil pressure was obviously at 0 with no oil in it, thats when i checked it halfway home, and added 4 quarts at advanced. then it went back to 39ish stably. now when it idles it hovers around 25, then if i step on it to around 1500 give or take, it is back up around 39. then i let off drops to 25 ish..


Its a tapping and is faint, but loud enough to hear witht he hood closed.

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post #12 of Old 05-06-2012, 06:32 PM
MurdaJs
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Quote:
Originally Posted by sevenscrew View Post
there's a tapping sound from near the center of the intake manifold /engine. has a bad valve cover gasket leak. 196k

it matches the rpms and is more noticable since I put in a new muffler and tailpipe.


any ideas ?
Exhaust leak somewhere?
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post #13 of Old 05-06-2012, 06:36 PM Thread Starter
sevenscrew
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its from the engine bay, and like near the center of the intake manifold area, didnt use a stethoscope or anything. sound wasnt louder or anything with new exhaust, just now you can hear it more because the exhaust isnt so loud lol

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post #14 of Old 05-06-2012, 06:40 PM
MurdaJs
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Quote:
Originally Posted by sevenscrew View Post
its from the engine bay, and like near the center of the intake manifold area, didnt use a stethoscope or anything. sound wasnt louder or anything with new exhaust, just now you can hear it more because the exhaust isnt so loud lol
leaky exhaust manifolds sounds are often described as clicking/tapping and match rpms
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post #15 of Old 05-06-2012, 06:43 PM Thread Starter
sevenscrew
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how can i check? just look for visible cracks? stethoscope the manifold witha long screw driver?

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