4.7 clacking noise
Thread Starter
|
Registered User
Joined: Nov 2010
Posts: 23
Likes: 0
4.7 clacking noise
hi i have a 2005 dodge ram 1500 with the 4.7 motor with 68000 miles and i get an annoying clack clack clack noise on cold starts it quiets down once warm but what is it and if i crawl under the truck it almost sounds like it is coming from the oil pan by the drain plug could it be the oil pump
Veteran
Joined: May 2007
Posts: 359
Likes: 0
From:
4.7 Ram engines are known for cold start "ticking" either due to an exhaust leak at a manifold, or can be due to the cam chain tensioners bleeding down.
Regarding the cam chain tensioners: No matter what oil voscosity you run , it won't eleviate it. Synthetic oils do nothing to quiet it. You can either live with it, (assuming it's the cam chain tensioners and not the exhaust) or replace the tensioners.
Mine's done it since 35K, and has 81K on it now. Cold engine, 30-40 seconds at idle, or to the top of my street. Shuts up faster with engine rpms over idle. I've run Synthetic, Organic and every oil shy of Baby oil.....I figured I'd get in trouble if I got caught squeezing one hard enough to get 6 quarts.
I originally had an exhaust leak at 35K, but that's a different noise all together, IMHO.
Some have stated it's the lash adjusters.
This is what the manual states about that:
ROCKER ARM / ADJUSTER ASSEMBLY DESCRIPTION
The rocker arms are steel stampings with an integral
roller bearing. The rocker arms incorporate a 2.8
mm (0.11 inch) oil hole in the lash adjuster socket for
roller and camshaft lubrication.
DIAGNOSIS AND TESTING - HYDRAULIC LASH ADJUSTER
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylinder
head. Low speed running up to 1 hour may be
required.
(3) Turn engine off and let set for a few minutes
before restarting. Repeat this several times after
engine has reached normal operating temperature.
(4) Low oil pressure.
(5) The oil restrictor in cylinder head gasket or the
oil passage to the cylinder head is plugged with
debris.
(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker arm ears contacting valve spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maximum
extension and still leaves lash in the system.
(10) Oil leak or excessive cam bore wear in cylinder
head.
(11) Faulty lash adjuster.
a. Check lash adjusters for sponginess while
installed in cylinder head and cam on camshaft at
base circle. Depress part of rocker arm over adjuster.
Normal adjusters should feel very firm. Spongy
adjusters can be bottomed out easily.
b. Remove suspected lash adjusters, and replace.
c. Before installation, make sure adjusters are at
least partially full of oil. This can be verified by little
or no plunger travel when lash adjuster is depressed.
Regarding the cam chain tensioners: No matter what oil voscosity you run , it won't eleviate it. Synthetic oils do nothing to quiet it. You can either live with it, (assuming it's the cam chain tensioners and not the exhaust) or replace the tensioners.
Mine's done it since 35K, and has 81K on it now. Cold engine, 30-40 seconds at idle, or to the top of my street. Shuts up faster with engine rpms over idle. I've run Synthetic, Organic and every oil shy of Baby oil.....I figured I'd get in trouble if I got caught squeezing one hard enough to get 6 quarts.
I originally had an exhaust leak at 35K, but that's a different noise all together, IMHO.
Some have stated it's the lash adjusters.
This is what the manual states about that:
ROCKER ARM / ADJUSTER ASSEMBLY DESCRIPTION
The rocker arms are steel stampings with an integral
roller bearing. The rocker arms incorporate a 2.8
mm (0.11 inch) oil hole in the lash adjuster socket for
roller and camshaft lubrication.
DIAGNOSIS AND TESTING - HYDRAULIC LASH ADJUSTER
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylinder
head. Low speed running up to 1 hour may be
required.
(3) Turn engine off and let set for a few minutes
before restarting. Repeat this several times after
engine has reached normal operating temperature.
(4) Low oil pressure.
(5) The oil restrictor in cylinder head gasket or the
oil passage to the cylinder head is plugged with
debris.
(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker arm ears contacting valve spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maximum
extension and still leaves lash in the system.
(10) Oil leak or excessive cam bore wear in cylinder
head.
(11) Faulty lash adjuster.
a. Check lash adjusters for sponginess while
installed in cylinder head and cam on camshaft at
base circle. Depress part of rocker arm over adjuster.
Normal adjusters should feel very firm. Spongy
adjusters can be bottomed out easily.
b. Remove suspected lash adjusters, and replace.
c. Before installation, make sure adjusters are at
least partially full of oil. This can be verified by little
or no plunger travel when lash adjuster is depressed.
Last edited by OldMoparMan; Apr 15, 2011 at 08:30 PM.