Author:
Date:
Subject:
Nate Nagel
2008-07-15 00:32:24
Re: Some details of the 2AZ-FE engine
Ed White wrote:
> "Built_Well" <[email protected]> wrote in message
> news:97101848-da38-42b3-88d7-6dcb0def23b9@s50g2000hsb.googlegroups.com...
>
>>Gonna write this stuff down and post it so I don't lose it. Had
>>to wade through a lot of pages to find it. The 5th Generation Camry's
>>2AZ-FE engine (an advanced powerplant, by the way)
>
>
> Advanced, in what way? Lots of comparable engines from many manufacturers. I
> have a hard time thinking of any engine that requires routine valve
> adjustment as "advanced."
Solid lifters = less reciprocating mass, and higher RPM potential
because the lifters won't pump up. The reduction in reciprocating mass
allows the use of lighter valve springs for less friction. Doing away
with the need for oil feed to the lifters reduces the required capacity
of the oil pump and therefore pumping losses.
With careful design and material selection, the required valve
adjustment intervals can be quite long. I don't think I ever adjusted
the valves on my old Scirocco; by the time I'd collected the required
tools and shims I realized that the darn thing would just keep running
indefinitely whether I adjusted them or not. (for some inexplicable
reason, VW went to hydraulics anyway.) I did have the valve cover
gasket replaced once while it was in my care but I can't even remember
if I asked the mechanic to check the valve clearances or not. (don't
remember why I didn't do it myself.)
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
Author:
Date:
Subject:
larry moe 'n curly
2008-07-15 01:53:58
Re: Some details of the 2AZ-FE engine
Ed White wrote:
> I was shocked when I found out my Nissan Frontier requires valve
> adjustment. You have to love the chutzpa of the Nissan engineers. The engine
> in my Frontier requires valve adjustment only when the valve noise is
> objectionable. It is going to be damn loud before I'll spend hundreds (maybe
> thousands) to have the valves adjusted. I assume the engineers at Nissan
> (and Toyota) have designed the valve system so that the valve clearance
> increases with wear - else you run the risk of burning valves if the
> clearance goes too low (learned from sad experience on older engines).
I have a 1998 with KA24DE engine. How can a valve adjustment with
this type of engine be so expensive? Are they charging that much for
the shim disks?
Author:
Date:
Subject:
C. E. White
2008-07-15 07:35:24
Re: Some details of the 2AZ-FE engine
"larry moe 'n curly" <[email protected]> wrote in message
news:a197d3c0-d203-4aee-b23a-aaf08ef2c08a@56g2000hsm.googlegroups.com...
>
>
> Ed White wrote:
>
>> I was shocked when I found out my Nissan Frontier requires valve
>> adjustment. You have to love the chutzpa of the Nissan engineers.
>> The engine
>> in my Frontier requires valve adjustment only when the valve noise
>> is
>> objectionable. It is going to be damn loud before I'll spend
>> hundreds (maybe
>> thousands) to have the valves adjusted. I assume the engineers at
>> Nissan
>> (and Toyota) have designed the valve system so that the valve
>> clearance
>> increases with wear - else you run the risk of burning valves if
>> the
>> clearance goes too low (learned from sad experience on older
>> engines).
>
> I have a 1998 with KA24DE engine. How can a valve adjustment with
> this type of engine be so expensive? Are they charging that much
> for
> the shim disks?
I have the V6 in my Frontier. To replace the shims you have to remove
the cams - 4 of them. Hopefully I'll never need to have it done. I
guess things are much better now. Years ago I had a Jensen-Healey with
a DOHC 4 cylinder engine. Adjusting the valves was a nightmare - but
still easier than for the Frontier V-6.
Ed
Author:
Date:
Subject:
EdV
2008-07-15 09:50:15
Re: Some details of the 2AZ-FE engine
On Jul 14, 11:34 pm, "Ed White" <[email protected]> wrote:
> "Built_Well" <[email protected]> wrote in message
>
> news:97101848-da38-42b3-88d7-6dcb0def23b9@s50g2000hsb.googlegroups.com...
>
>
>
> > Gonna write this stuff down and post it so I don't lose it. Had
> > to wade through a lot of pages to find it. The 5th Generation Camry's
> > 2AZ-FE engine (an advanced powerplant, by the way)
>
> Advanced, in what way? Lots of comparable engines from many manufacturers. I
> have a hard time thinking of any engine that requires routine valve
> adjustment as "advanced." But I guess that is also a trend these days. And
> since most people ignore the routine valve clearance checks, I guess it is
> irrelevant. I was shocked when I found out my Nissan Frontier requires valve
> adjustment. You have to love the chutzpa of the Nissan engineers. The engine
> in my Frontier requires valve adjustment only when the valve noise is
> objectionable. It is going to be damn loud before I'll spend hundreds (maybe
> thousands) to have the valves adjusted. I assume the engineers at Nissan
> (and Toyota) have designed the valve system so that the valve clearance
> increases with wear - else you run the risk of burning valves if the
> clearance goes too low (learned from sad experience on older engines).
>
> > is the same engine that was used in the '01 Highlander SUV.
> > 5th Generation Camrys cover Model Years '02 - '06.
>
> It is still used today in Camrys, RAV4s, and ?
>
>
>
> > The cylinder block is made of aluminum alloy. It uses aluminum
> > pistons, high-strength steel connecting rods and caps, forged steel
> > crankshaft, and, IIRC aluminum camshafts. The VVT-i only works
> > on the intake camshaft, not the exhaust camshaft. It varies
> > the timing of the intake valves. There are two intake valves per
> > cylinder and two exhaust valves per cylinder. Having two of
> > each increases the total port area, so more air can flow into
> > and out of the combustion chamber. As the manual's authors
> > write, "Intake and exhaust efficiency has been increased due
> > to the larger total port areas."
>
> > The cylinder head cover (not to be confused with the cylinder
> > head) is made of magnesium alloy for lighter weight. I think
> > cylinder head cover is synonymous with "valve cover," but the
> > Camry manual refers to it as the "cylinder head cover."
>
> > Since the manual doesn't mention what the cylinder head, itself,
> > is made of, I will assume iron, but just an assumption.
>
> Nope, it is aluminum.
>
> > The cylinder head gasket, used between the aluminum engine block
> > and the (iron?) cylinder head is a steel-laminate type of
> > material. Any concern about electrolysis taking place between
> > the steel-laminate and aluminum?
>
> Nope, but be sure to use the recommended coolant.
>
> > When the service and repair manual says the dry weight of the
> > engine is 267 pounds, does that include the crankcase, crank,
> > cylinder head, and valve head with camshafts--or does the
> > weight only include the engine block without crankcase
> > and cyclinder head, etc.?
>
> Everything that makes up the main engine assembly (block, pistons, heads,
> cams, etc.) but no oil or water. Probably does not include accesorries
> (alternator, starter). May or may not include intake system. Probably
> includes intake to the throttle body.
>
> > The crankshaft and camshafts are connected by a timing chain,
> > not a belt.
>
> Common practice these days. Cam belts are mostly on the way out for modern
> engines.
>
> > The oil pump is located behind the timing chain cover at the
> > front bottom of the engine, even lower than the crankshaft. The oil
> > pump has its own short section of chain that's connected to the
> > crankshaft. Couldn't tell from the picture if this is a second,
> > dedicated chain, or just part of the larger chain that ascends to
> > the camshafts.
>
> Completely separate chain (referred to as the No. 2 Chain Sub-assembly).
>
> > Double overhead cams, don't ya know (DOHC) :-)
>
> > If I had to guess, I'd say the oil pump has its own dedicated
> > short chain that's separate from the timing chain, ie., camshaft
> > chain..
>
> Correct.
>
> Ed
Is the 2AZ-FE considered a direct injection engine?
Author:
Date:
Subject:
C. E. White
2008-07-15 13:24:36
Re: Some details of the 2AZ-FE engine
"EdV" <[email protected]> wrote in message
news:8ce8d082-d6c7-4195-992c-2cf1e40b68cb@59g2000hsb.googlegroups.com...
> Is the 2AZ-FE considered a direct injection engine?
No.
Ed
Author:
Date:
Subject:
Built_Well
2008-07-15 16:35:59
Re: Some details of the 2AZ-FE engine
C. E. White wrote:
>
> EdV wrote:
>>
>> Is the 2AZ-FE considered a direct injectin engine?
>
> No
=============
The 2AZ-FE is a direct injection engine. It does not
use a mechanical distributor, and the engine does
use a crankshaft sensor and a camshaft sensor, among
other things.
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