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Discussion Starter #1
1993 164L manual transmission. I'm helping my brother replace timing belt, water pump, adjust valves, etc. Prior to removing the old timing belt I'm checking all timing marks: 1. scribed line on front pulley; 2. mark on flywheel (drill hole on the outter rim of flywheel?); 3. marks on cam shafts 4. position of #1 piston.

A. When the scribed line on the front pulley is at the pointer on engine block (approximately 11 O' clock) #1 piston is at it's highest point. B. When the cam shaft marks line up with the cam shaft caps the drill hole in the flywheel is at the mark on the bell housing.

When the marks in B. above are lined up, it occurs about 5 front pulley teeth before A. above.

Shouldn't all of these line up at the same time??

Thanks
Rick
 

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I recall a bulletin about US spec engines and the flywheel timing mark (but not the specifics - very useful...), but FWIW, over here, the timing reference on the flywheel is usually a small line scribed on the face.

Also, I have an engine where one of the factory applied marks on the camshaft bearing cap on the rear head is wrong - I kid you not! It was this that finally convinced me to ignore the marks and work it out from scratch. As it happened, once I had done this, I found that the front pulley mark was OK, the flywheel mark was OK, and the small scribe lines on the camwheel centres were fine too, as was the front head cam-cap scribe mark.
 

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I always use the front pulley mark. There was a TSB on the rear mark where it was put into the manual wrong. It states that the hole is used for the european models and the scribed line is for the US cars to set TDC.
So.. If you are using the book printed in '91 for the 164 change the info on pages 00-36, 00-43 & 01-90 so you don't miss it again.
Once you line up the front mark you can double check the rear. Usually it is spot on.
Hope this helps.

Paul
 

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For the first time, you should take the valve covers off and verify the cam pulley marks are correct by checking the cam marks with the bearing caps. Now you can mark the pulleys and the block as you see fit for next time. I never use the flywheel mark at all for T/B replacement, just the crank pulley, cam pulleys and camshafts/caps (first time only). Download the cam timing template as well.
Charles
 

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For the first time, you should take the valve covers off and verify the cam pulley marks are correct by checking the cam marks with the bearing caps. Now you can mark the pulleys and the block as you see fit for next time. I never use the flywheel mark at all for T/B replacement, just the crank pulley, cam pulleys and camshafts/caps (first time only). Download the cam timing template as well.
Charles
My point was....I did that and eventually found the cam-cap mark was wrong on one bank. Maybe I've got the only one in existence that's wrong, but those marks look like they are applied by hand. I had to resort to measuring lift on overlap to get it right as I didn't know what to trust. However, it turned out that the scribe marks on the pulley hubs where spot-on. Also, I find them to be more accurate to work from (larger diameter, smaller mark, much smaller errors), same for the front pulley vs. flywheel marks - prefer the flywheel. Mind you, once you've established which marks are correct, a one-tooth error is easy enough to see either way.

I should say, I got into the whole doubting the timing issue because the engine wouldn't idle right and it always sounded a wee bit 'Subaru' if you know what I mean. It now idles a lot better and sounds as it should. It used to pink as well, and when I first got the car, it was peppered with different DIY timing marks - all things that baffled me at the time, but made complete sense once I finally went back to first principles with it.
 

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Charles, Not to change the subject but... Do you remember what percentage one needs to blow up the template in order to make it fit? I had it written down after several trial and error prints and lost it.

Paul
 

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Another question:
Does the template apply to a '93 164S?

The template says '91 164L and was just wondering.......
 

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Print at 100%. It will work for all the 164 12V engines in the US anyway.
Charles
 

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Discussion Starter #10
I'm still puzzled. This car runs well, but:

The timing marks on the cams line up when the HOLE on the flywheel outter rim lines up with the line on the bell housing. I CAN NOT FIND A SCRIBED LINE ON THE FLYWHEEL. This occurs when the scribed line on the front pulley is 5.5 teeth, about 30 degrees, advanced of the pointer (an aluminum post located at 11 o-clock) on the front of the engine.

TDC, #1 piston is up, occurs when the scribed line on the front pulley lines up with the pointer on the front of the engine. I determined TDC by placing a tape measure in #1 cylinder, rotating the engine and finding the shortest measurement. That means the cam marks are currently set 30 degrees advanced of TDC on the crank, which I think equates to 15 degrees advanced on the cams.

The CD-manual I have has stuff crossed out regarding the flywheel timing mark. It seems to say do NOT use a hole as reference, use a line. But this flywheel does not have a line and existing timing belt is lined up with a HOLE.

I observed the valves open and close during two revolutions of the crankshaft, it seems to me that the valve operation is advanced relative to piston location.

I used the cam template mentioned above, it was correct when I checked with the flywheel hole at the bell housing mark, but wrong, too much clockwise, when I moved front pulley forward to line up with pointer.

1. Is it possible that the factory never put the scribed line on the flywheel?
2. Could this engine run with the cams 15 degrees advanced?
3. Any other comments?

Thanks
Rick
 

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I have yet to ever even look for the flywheel mark. I use the front crank pulley "gap" and pointer.
Charled
 

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Discussion Starter #12
Charles,

I realize that should work, but in this case, the engine was running and I have not taken the timing belt off yet. When the cam marks are lined up, the pointer at the front pulley is 30 degrees advanced of the scribed line on the pulley.

So when I replace the belt would I reinstall it the same as the existing belt or retard it by lining up the pulley scribed line with the pointer?

Your method would put the cam marks at TDC of #1 piston, which I think is correct, but I would like to be sure.

Rick
 

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Line up scribed mark between two teeth on front of crank pulley with triangular pointer on front cover at about 11 oclock position to set #1 piston at top dead center and then see when cam timing mark are at using pdf template on cam pulley hub scribed lines or timing marks on cam bearings caps - 1 o'clock rear cam and 11 o'clock front same on bearing caps as on pulley hubs.

http://www.alfabb.com/bb/forums/265321-post1.html Crank pulley bulletin picture.
 

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If the flywheel has been refaced at any point in it's life, the mark on it would have been lost (unless the machinist took it upon himself to restore it afterward).

Given the apparent ambiguity here, I reiterate....don't trust ANY marks. Measure it from first principles so you KNOW it's correct. Who knows what's been done to it in the past as far as mix & match of parts, odd marks, whatever. Yes, the stock marks SHOULD work just fine, but as I keep saying, I had one with a factory applied mark that was simply wrong, and from the look of things, I wasn't the first person to be led a dance by it.

If the crank was 30 degrees out WRT cams - not only wouldn't it run, it probably wouldn't even turn over, so again, for whatever reason, there's some confusion here about which marks are which.

I recently saw a picture of a front crank pulley from one of these where it had worked loose and chewed away at the keyway putting the thing miles out of place. Perhaps you are facing something like this??

Cam timing shots are from my motor - these are how it ended up when properly timed by measuring cam lift on overlap and ignoring all marks. As it happened (and not too surprising...), TDC determined with a DTI on #1 coincided perfectly with the scribed line on the flywheel and perfectly with the crank pulley mark (as close as I could determine), the scribe lines on the front edges of the camwheel hubs lined up at 69.5 and 70 degrees on the template IIRC - very close to ideal certainly. I forget what I did to convince myself the cam cap mark was correct and the scribe was wrong when I first assembled this engine, but I clearly deluded myself about something! Timed on the cam cap marks, this engine sounded 'off', it pinked and had a habit of stalling. Same behaviour on both OEM Motronic and the aftermarket ECU it now runs. Obviously we dialled out the pinking on the aftermarket system, but to do so we ended up with stupidly retarded timing as a consequence. Reminds me I really should try winding in a few more degrees some time and see what happens.

Anyway...best of luck with it.
 

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Corse Chris is making the point that you can't assume anything really regarding marks. I believe he's working with a 24V engine in a Stratos replica IIRC. Your 12V car could have mark issues as well though things will be a little easier to work with, with fewer cam pulleys. You do need to dig into it and figure out what's going on and confirm some marks. Is the #1 piston at TDC when the front crank marks are lined up? You can pull the plug and run a rod or even long screwdriver down there. Rotate the engine and confirm TDC and the marks. Watch the rod go up and down and even measure it if you want to be spot on. Obviously do this with the TB still on. You have been running it this way so I assume even if it's out, you aren't going to bend valves if you haven't already. Then with the engine at TDC (confirmed), I would remove the belt and time the cams using the cam and cap marks and confirm the cam pulley marks to be correct or not correct. If they agree with each other and the template than you should be good. I think your engine is currently out of time and the slip occurred at the crank, which would explain why the two cam pulley are in time with each other but not with the front crank pulley and the crank is advanced relative to the cams.
Charles
 

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Only a humble 12V for me Charles. You're right about the place it's fitted though ;) I also have a 155 V6 which has a 2.5 12V V6 in it and have had a couple of 12V 164s. Running a 24V engine in the 166 of course. I've yet to do anything to that one though. In some ways' they are easier I think as you just use the camlocks on them, so given stock parts, you can't go wrong.

That chewed up pulley picture was from a 24V (I think). Not my car, just someone on another forum I frequent talking about cambelt timing, funnily enough ;)
 

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I traded for a 86 GTV6 once that did not run right. Turned out the aux shaft gear for oil pump and distributor has a groove in it around alignment dowel pin so ignition timing was all over the place from BTDC to ATDC about 30-40 degrees so affect pretty much the same as crankshaft cog gear shown in picture above.

Back to basic here on this thread. With sparkplugs removed (at least #1 rear head closest to upper mount). Insert "dial indicator tool" aka long screwdiver into spark plug hole, turn crank shaft counter clockwise until mark on crank shaft front pulley lines up with mark on front cover at 11 oclock and screwdriver indicator rises to highest point.

This will verify mark on front pulley correct when lined up with triangular pointer on front cover. Note: this point is same as on GTV6 and Milano (75) but has pointer pin removed so just small hole in center of triangluar piece where pin would go on those models.

Now if cam pulley shiny center hubs have scribe marks on them them need to be 1 o'clock on rear cam and 11 o'clock on front or if you have cam covers off refer to marks on cam pulleys they should also be at 1 rear and 11 front head.

See if this link that is one of many in second link below maybe some of those will show you pictures , etc that will help:
http://www.alfabb.com/bb/forums/164-168-1991-1995/152373-setting-up-alfa-164-engine-cam-timing-belt-tensioner.html

http://www.alfabb.com/bb/forums/164-168-1991-1995/141647-alfa-164-alfisto-steves-maintenance-tips.html
 

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Discussion Starter #18
Regarding CorseChris 8/14 @ 3:51am: I dont think my problem is a failed key, my cams are advanced of the crankshaft, if the key failed I think the cams would be retarded relative to the crankshaft.

Rick
 

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Discussion Starter #19
chazzyD 8/14 @11:16am: I think Charles is is right when he says not to trust all the marks. At this point I think the last guy who worked on this put the timing belt on with the flywheel HOLE lined up, which I think was how some of the manuals were incorrectly written. But what really puzzles me is that the engine ran well even with this advanced cam setting.

I have more to report, I dont know if I will get to it tonight.

Rick
 

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Discussion Starter #20
“Timing mark(s) confusion” , 08/15/09, update

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The engine seems to run fine.
I have not yet removed the old belt.
I can NOT find a scribed line on the flywheel (face).

When the marks on the cams line up with cam caps:
- HOLE in flywheel outer edge matches bell-housing line
- #1 piston is NOT yet at TDC
- pointer is 5.5 sensor teeth BEFORE line on front pulley
- (NOTE: 5.5 sensor teeth = 34 degrees; 34 degrees = 2
teeth on the timing belt crankshaft sprocket)

When the scribed line on front pulley DOES match pointer:
- #1 piston is at highest point, TDC
- cam lines are BEYOND cap lines, they do NOT line up

Template showed 69 and 72.5 when cam marks lined up, but
- front pulley line 5.5 away from pointer, NOT at TDC!

Based on: front pulley, cam marks, #1 piston TDC:
- I think the current belt was installed incorrectly
- incorrectly installed using flywheel HOLE to line up

Questions:------------------------------

1. Did manual originally say “line up hole on flywheel“?
2. Should ALL timing marks line up when #1 at TDC?:
- front pulley; cams; flywheel;
3. Could engine run with cams advanced?
- I think timing belt off by 2 teeth on crank sprocket
4. Has anyone heard of this error before?

---------------------------------------
Thanks
Rick
 
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