Bookmarks

Yahoo Gmail Google Facebook Delicious Twitter Reddit Stumpleupon Myspace Digg

Search queries

how long will 4mm brake pads last, ga16 valve clearance, galsawya.com, suzuki GT125 BTDC, sprocket xt 600, cardaq2534, how to set ignition timing with timing light 1.6dohc efi ford laser, kirsty wark tits, difference between stored and pending codes, dr 350 cdi

Links

XODOX
Impressum

#1: Overhead cams have valve lifters ?

Posted on 2006-03-12 16:44:38 by user132384

I'm getting lots of loud clacking on a 96 Nissan Sentra 1.6 Liter.
Sounds like it's coming from the head. It has overhead cam, I believe.
I had thought OHC did not use hydraulic valve lifters, so I thought
sludged up lifters would NOT be causing the clacking.

The clacking comes and goes, does not follow a predictable pattern. It
has been happenning for about 2 years, and is slowly getting worse.

The head looks clean when you remove the oil filler cap and look in
with a flashlight, and plenty of oil splashes out all over everything
if you open the cap with the engine running.

Oil and filter changes have been done every 5K to 7K.

Thanks

Report this message

#2: Re: Overhead cams have valve lifters ?

Posted on 2006-03-12 17:29:50 by Woody

Your valve rockers need adjusted.


&quot;Caprice85&quot; &lt;<a href="mailto:user132384&#64;aol.com" target="_blank">user132384&#64;aol.com</a>&gt; wrote in message
news:<a href="mailto:1142178278.303679.70720&#64;e56g2000cwe.googlegroups.com..." target="_blank">1142178278.303679.70720&#64;e56g2000cwe.googlegroups.com...</a>
&gt; I'm getting lots of loud clacking on a 96 Nissan Sentra 1.6 Liter.
&gt; Sounds like it's coming from the head. It has overhead cam, I believe.
&gt; I had thought OHC did not use hydraulic valve lifters, so I thought
&gt; sludged up lifters would NOT be causing the clacking.
&gt;
&gt; The clacking comes and goes, does not follow a predictable pattern. It
&gt; has been happenning for about 2 years, and is slowly getting worse.
&gt;
&gt; The head looks clean when you remove the oil filler cap and look in
&gt; with a flashlight, and plenty of oil splashes out all over everything
&gt; if you open the cap with the engine running.
&gt;
&gt; Oil and filter changes have been done every 5K to 7K.
&gt;
&gt; Thanks
&gt;

Report this message

#3: Re: Overhead cams have valve lifters ?

Posted on 2006-03-12 18:20:22 by Backbone

&quot;Caprice85&quot; &lt;<a href="mailto:user132384&#64;aol.com" target="_blank">user132384&#64;aol.com</a>&gt; wrote in message
news:<a href="mailto:1142178278.303679.70720&#64;e56g2000cwe.googlegroups.com..." target="_blank">1142178278.303679.70720&#64;e56g2000cwe.googlegroups.com...</a>
&gt; I'm getting lots of loud clacking on a 96 Nissan Sentra 1.6 Liter.
&gt; Sounds like it's coming from the head. It has overhead cam, I believe.
&gt; I had thought OHC did not use hydraulic valve lifters, so I thought
&gt; sludged up lifters would NOT be causing the clacking.
&gt;
&gt; The clacking comes and goes, does not follow a predictable pattern. It
&gt; has been happenning for about 2 years, and is slowly getting worse.

The GA16DE requires that you periodicaly check for valve clearance - says so
in you owners manual!!
A GA16DE is a DOHC engine!!!

--
There are no words that can be heard unless someone listens....
Remove *flaps* to reply

Report this message

#4: Re: Overhead cams have valve lifters ?

Posted on 2006-03-12 20:15:14 by Comboverfish

Caprice85 wrote:
&gt; I'm getting lots of loud clacking on a 96 Nissan Sentra 1.6 Liter.
&gt; Sounds like it's coming from the head. It has overhead cam, I believe.
&gt; I had thought OHC did not use hydraulic valve lifters, so I thought
&gt; sludged up lifters would NOT be causing the clacking.
&gt;
&gt; The clacking comes and goes, does not follow a predictable pattern. It
&gt; has been happenning for about 2 years, and is slowly getting worse.
&gt;
&gt; The head looks clean when you remove the oil filler cap and look in
&gt; with a flashlight, and plenty of oil splashes out all over everything
&gt; if you open the cap with the engine running.
&gt;
&gt; Oil and filter changes have been done every 5K to 7K.
&gt;
&gt; Thanks

Backbone's reply is right. To furthur the discussion, your engine uses
replaceable shims to control valve adjustment. They don't usually
wear. If one did wear, it would probably mean that it's companion cam
lobe was worn, too. A more likely cause of your random noise, assuming
it is valve related, is that you have massive carbon build up on the
backs of the intake valves. This keeps the valves from fully seating,
and can turn a recommended lash of .010&quot; into .030&quot; over time. The
carbon is forgiving enough that it can allow the valve to close
sometimes, and can hold it open others. Temps and fuel soaking have a
role in how hard or soft it gets.

The valve followers or 'buckets' that move up and down in the head can
get stuck, but it's unlikely if you did regular oil changes and the
head looks clean through the oil cap as you state.

Adjusting valve clearances on this engine is an ordeal. I would have
someone verify that it sounds like a valve noise, then investigate top
engine cleaners, Chevron Techron additive, or a Motorvac service to try
to break loose the carbon on the valves. You could then *check* the
clearances (fairly easy) and make sure they were in spec.

If your second opinion doesn't agree with the valve noise diagnosis,
you may have a stretched timing chain or broken guide. I don't know
the reason, but I have seen stretched chains cause a similar noise that
'comes and goes'.

BTW, I have yet to see a Sentra of that bodystyle that wasn't leaking
at the front crank seal. Just a FYI, you might want to check that when
you are done with the noise issue.

Toyota MDT in MO

Report this message

#5: Re: Overhead cams have valve lifters ?

Posted on 2006-03-13 16:36:52 by user132384

Thanks.

Woody and Backbone : the mechanics keep telling me there is no
adjustment to be made to the valves. One of them is a former Nissan
mech, too. I guess they just don't want to mess with it. :) They
didn't mention checking the valve clearance either.

Yes, the manual says for the ga16de engine, that if the valves get
noisy, to inspect valve clearance. I don't know if I have the ga16de
though. It's a 4 cyl 1.6 Liter automatic trans.

Toyota MDT : I also get a rasping, buzzing, sound , like a baseball
card in the spokes of a wheel, often in the high rpms of each gear,
only at light throttle. Could be the timing chain ?

Valve cover looks easy to remove. Is there a way to manually rotate the
crank with a wrench, to get the valves in the right spot to check ?

Report this message

#6: Re: Overhead cams have valve lifters ?

Posted on 2006-03-13 19:55:11 by Comboverfish

Caprice85 wrote:
&gt; Yes, the manual says for the ga16de engine, that if the valves get
&gt; noisy, to inspect valve clearance. I don't know if I have the ga16de
&gt; though. It's a 4 cyl 1.6 Liter automatic trans.

That's what you have. There may have been a 2.0 available that year,
but the 1.6L in 1996 is a GA16DE.
&gt;
&gt; Toyota MDT : I also get a rasping, buzzing, sound , like a baseball
&gt; card in the spokes of a wheel, often in the high rpms of each gear,
&gt; only at light throttle. Could be the timing chain ?

I would think the timing chain would be noisier with engine at idle,
listening under the hood.

&gt; Valve cover looks easy to remove. Is there a way to manually rotate the
&gt; crank with a wrench, to get the valves in the right spot to check ?

Yes, you manually rotate it with a wrench. Get a Nissan/Mitchell/Motor
service manual or copies of the appropriate pages from the library.
While checking clearance is easy and requires few tools or savvy, it
should only be attempted by a beginner after reading/following the
procedure right out of the manual.

Toyota MDT in MO

Report this message