LT5 Assembly Project

[LGAFF]

I am taking this apart....everything is going to be cleaned prior to reassembly.

LGAFF
92 ZR1
#234

[LGAFF]

Originally Posted by Pete

Lee,the front cam caps have the thrust bearing in them.
I would be careful trying to pull the cams down with those little caps and screws.

Pete

Pete,

I am not torquing down the cam caps, I am just pointing out the main purpose of the caps is to hold the cams in place not truly a bearing as the cam covers....

[Zr1 Destroyer]

Originally Posted by LGAFF

I am taking this apart....everything is going to be cleaned prior to reassembly.

LGAFF
92 ZR1
#234

Just be careful.....cleaning your valve train components will not de-magnatize them.


I used a magnet to remove the lifters on my gto motor rebuild when I was 16 and my dad just about had a stroke and made me replace all the lifters and toss the old ones that were in perfect shape........friggin old school.

[tomtom72]

Lee,

I would just like to say thanks for all this posting that you're doing. It's alot different seeing these pictures as opposed to reading the FSM and even watching the CD training film.

I'm sure glad that you are taking the time to present this in pictures & text! I'm thankfull as I've never seen any of this stuff...Thanks again!


Tom

[LGAFF]

Took the cams apart today:

Front shot of cam snout with hardware in place.



The cam has a set of timing chain gears on it; this slides on the cam, the gears have timing holes in them....they simply slide onto the cam, in no particular position.

For cam timing, each cam has a timing hold down hole in it. In order to set the timing, the cam is placed in the cylinder head and the hold down holes are aligned with hold down holes in the cam hold down....this are held in place with pins that hace handles on them. Once in place, a D Center plate with timing holes slides onto the cam, up against the timing gears. The cam snout itself has a D-Faced suface that helps in holding the gear in place. After pinning the cams, the slcak is removed and I beleive the engine is then rotated 720 degrees, the pins are then reinserted to veridy that timing is correct, and then the washers are slid into palce, and the bolt torqued down on the snout. The cam can be held in place with a 19mm wrench on the back side of the cam, allowing you to tighten the 14mm Cam bolt.

Pics of cam hardware:

lft to rght; Cam gear, D-center plate(with pin above, washer, bolt)


Pic of Gear pinned to D-Center plate(off the cam)


LGAFF
92 ZR1
#234
As always...experts pipe up if any misinfo

[LGAFF]

Here is a pic of the cam snout, note the D-Shape to lock help hold the cam gear in palce once it is pinned:



There is some play in the gear even after pinning, however this is eliminated I beleive once the bolt is torqued down.........I do have one issue, once the cams had some snout damage when I bought it....you can see it here:



It was torqued down well, however once the bolt is removed there is signifcant play. I assume it may be a nonissue as when the cams are timing they are held into place by the pins but looking for thoughts....here is a video of the difference in play, remeber this is pined but not bolted down:

[LGAFF]

In terms of telling one cam from another there are several ways:

Each can has RH and LH cast into them. They also have bands at the front which are either raises flat or a combo:

Pic of bands:



(As you can see the lower bands I am pointing to show a LH Intake, upper LH exhaust)

LH E= 2 raised bands
LH I= 1 flat and 1 raised

RH E: 1 raised
RH I: 1 flat

**The reluctor is always on the LH exhaust.

[LGAFF]

To clarfy here is a shot of what a cam hold down pin looks like:

http://www.handsontools.com/Kent-Moo...et_p_6263.html

Here is a video of how it would be installed....except I am use a torx screwdriver for demo purposes......there are four hold downs to insert two for each cam, this sets the factory timing....of course the crank is positioned by rotatating the crank until it locks into place using putitng an interference tool into the crank position sensor, which then locks into place on a specific position on the reluctor.
http://s134.photobucket.com/albums/q...t=DSCN0374.flv

Here is a drawing of the crank tool, slot at the top slips into the slot in the reluctor.
http://www.handsontools.com/Kent-Moo...et_p_6264.html

Not easy but not the magic one would think.

LGAFF
92 ZR1
#234

[8upZR1]

The first time I took LT5 apart I was kinda let down by the simplicity, especially after everyone I talked to hyped it up as being some insane super exotic deal. I was extremely happy to discover the built in adjustability of the cam gears though. Not many OEMs design adjustability into there valvetrains.

Another way to ID the cams is to look at the profiles. You can tell the intake cams cause they have different lobes for the 2 intake valves.
The driver side exhaust cam has the ring for the position sensor.
I dunno if there is an easy marking to tell the pass and driver side intake cams. I just keep them with their exhaust cam.

[Pete]

Originally Posted by 8upZR1

Another way to ID the cams is to look at the profiles. You can tell the intake cams cause they have different lobes for the 2 intake valves.
The driver side exhaust cam has the ring for the position sensor.
I dunno if there is an easy marking to tell the pass and driver side intake cams. I just keep them with their exhaust cam.

I can tell the cams blind folded that's scary.

Another way to tell left or right intakes is the center bob weight's are same diameter as the exhaust,basicly left side exhaust and intake are the big bob weights the right side have small ones.

Also the front snouts of the cams are different from left to right longer/shorter.

Pete