Cam Sprocket Alignment for Valve Adjustment

[chopper]

I reinstalled my timing belt. Found the compression stroke for cyl. #1. Aligned the belt marks with the cam sprocket alignment mark with the notch in the case and crank gear aligned with its mark and belt line.  I put the crank pulley on and made a slight adjustment to the zero on the plastic case.  Now I'm at TDC. 

For the Valve adjustment, the Haynes  manual states: "With the no. 1 piston at TDC on the compression stroke, the arrow mark on the right side camshaft sprocket should point up." It doesn't, it points about 22 degrees past straight up.  If I rotate the crank 2 full revolutions to bring no. 1 to the compression stroke and stop with the arrow pointing up I don't get to TDC.

What am I doing wrong?

Thanks,

Chopper

 

[el_freddo]

The mark on the crank cam gear is what you align the timing belt setup with, not the TDC mark on the crank pulley. 

If you’ve put the cam belt on using the TDC mark on the crank pulley/harmonic balancer, the engine will not run. 

That arrow is really handy for indicating which cylinder is on the firing stroke. 

Check out your cam timing and ensure the cam wheels/gears line up properly with the clogged belt gear mark on the crank. 

Cheers 

Bennie

[Rampage]

These should help you.

The cam sprocket marks are on the outer flat surface. Sometimes hard to see. Mark them with white paint or crayon.

[lmdew]

Nice Pics.

Great to add to the FAQ.

[ocei77]

Are you trying to do a valve adjustment or reinstall T belt correctly?

The above info is correct for T belt install.

What engine and year?

O.

[el_freddo]

3 minutes ago, ocei77 said:

Are you trying to do a valve adjustment or reinstall T belt correctly?

Valve lash adjustment - I thought he lined the TDC mark on the crank pulley/harmonic balancer to install the belt. 

Re-reading the original post this morning I’m thinking that @chopper is using the timing mark on the crank cam gear for TDC. The timing for TDC must use the crank pulley/harmonic balancer or go by the arrow (not the cam timing mark) on the LHS cam wheel.

Cheers 

Bennie

[Rampage]

[chopper]

I am doing both: Installing the timing belt and then adjusting the valve clearance on an EJ22, 2.2L. a 1995 with cams and rocker assemblies from a '97 2.2L.  I probably should have made two separate posts but they are related.

Timing Belt: The the cam sprocket mark and crank sprocket arrow are aligned with the respective marks.That is understood.

Note that the arrow on the sprocket is about 22 degrees past straight up (Rampages first diagram)

It just so happens that if you install the belt cover and crank pulley the crank pulley mark will line-up with the zero on the belt cover. That being TDC. I have physically probed cyl. 1 and it is at the top of its stroke.

Question 1: During the timing belt installation with the camshaft sprocket properly aligned, wouldn't that put the cam over cyl. 1 in a neutral position?  In this position the intake and exhaust rocker arms are not in contact with the valve stem.  That's how it is on mine. When I have installed the '97 cam and rocker assembly I rotated the crank 1/2 turn and checked each cylinder for the valve clearance and coincidentally each happened to be within specs. So, in this cam/crank position combination non of the rockers were in contact with the valves. 

Valve Clearance Adjustment:  The 2nd diagram that Rampage presented says to bring cyl. 1 to TDC by rotating until the the arrow on the cam sprocket is straight up putting cyl 1 at TDC.  If the cam sprocket arrow is straight up, the crank pulley is NOT on the zero mark on the belt cover. The pulley mark will be before the zero mark (before TDC).

Question 2: Why is Subaru calling this TDC when it is not.

I am confused about this because it looks like conflicting information to me. I spent 10 years working with VW engines and this is my first Subaru engine.

I do appreciate you taking the time to clear this up for me.

Chopper

[heartless]

2 hours ago, chopper said:

I am doing both: Installing the timing belt and then adjusting the valve clearance on an EJ22, 2.2L. a 1995 with cams and rocker assemblies from a '97 2.2L.  I probably should have made two separate posts but they are related.

Timing Belt: The the cam sprocket mark and crank sprocket arrow are aligned with the respective marks.That is understood. [/quote]

Apparently it is not being understood.. you do not use the arrow when installing the belt!  The arrow has NOTHING to do with belt installation.

 

when installing the belt, you need to be using the hash marks (circled in red here) (1st set of images posted by Rampage)

Quote

Question 1: During the timing belt installation with the camshaft sprocket properly aligned, wouldn't that put the cam over cyl. 1 in a neutral position?  In this position the intake and exhaust rocker arms are not in contact with the valve stem.

Yes, that is exactly how it is supposed to be for INSTALLING the belt..

The ARROW is used for adjusting the valve lash, as described in the 2nd set of images posted by Rampage.

Installing a belt, and adjusting the valves are two completely separate procedures.. you need to follow the correct procedure for installing the belt, then move to the correct procedure for adjusting valve lash - they are not one and the same.

 

[Rampage]

I never looked into it, but they want the timing belt installed in that position. The first time I did the timing belt I noticed that the (passenger side) Right cam sprocket turns free (no valves open) and the Left cam has valves wide open (top of the lobe). I think it may be, so that the cams will stay put while installing the belt. Then they want it turned to adjust valve lash.

 

Edited May 16, 2020 by Rampage

[el_freddo]

The Crank timing gear mark is on the tab on the back of the gear under the crank sensor. 

The tab you’re looking for is just like the one in your pic but has a definite line printed in it. 

Your problem is either misaligned cam belt timing or a harmonic balancer/pulley where the rubber is deteriorated and the outer ring has slipped, moving the TDC timing mark orientation. 

But I’m thinking that it if you’re using that mark on the crank timing gear for the cam belt timing, this is what’s out and causing the issue. 

In theory, you could have the arrows on the cam wheel pointed in the right directions for cam timing TDC and do the clearances. But it probably wouldn’t run if the cam timing is out. 

Cheers 

Bennie

[chopper]

The Ah-Ha moment has occurred. I see the error of my ways.   Heartless is correct in interpreting I installed the belt then went immediately to the valve adjustment. . It is not one procedure. They are separate procedures. My first error occurred with using the wrong crank timing mark (which placed cyl 1. at TDC) and things snowballed from there.

For the timing belt I was using the hash marks on the cam sprockets, but my error was the mark on the crank gear. As el_freddo pointed out, the correct crank mark is the tab on the back of the crank gear. When using the correct crank mark, cyl. #1 is NOT at TDC.  I have used that mark before, but completely forgot about it this time.  If I would have used the correct crank timing mark the first time I would have never attempted the valve adjustment because Cyl. 1 is not at TDC for the belt installation. The belt is now installed correctly.

Now, I can roll the crank around until the cam sprocket arrows point up and proceed with the valve adjustment.

Thank you for struggling through this with me, it really had me confused.

Chopper

[heartless]

gotta love those "ah-ha" moments, lol

Glad you have it figured out now and good luck with the adjustments. hope it works for you.

[el_freddo]

Glad this is sorted mate! 

Have fun, chalk it up as experience! 

Cheers 

Bennie