Timing Issues (again)

[Pope1]

Guys, I'm still trying to get to the bottom of the timing issues on my car. I'm wondering whether I should take the timing belt off and either re-align the two cams relative to the crank or vice versa. Really need some advice please as I am not sure what to do, if anything. Here is the situation.

If I align the two cam wheels with their pointers like this
http://home.caribsurf.com/chrysalis/images/cams.jpg

then the crank looks like this
http://home.caribsurf.com/chrysalis/images/crank.jpg

However, I am 99.9% sure that mark 3 is TDC, not mark 1. If I align mark 3 with the pointer like this
http://home.caribsurf.com/chrysalis/images/crank2.jpg

then the cam wheels look like this
http://home.caribsurf.com/chrysalis/images/cams2.jpg

What would you recommend?

1) Leave the thing alone, unless you really like fiddling.
2) Position the cam wheels as in the first photo, take belt off and rotate crank to line up with pointer, refit belt and re-tension.
3. Position the crank as in photo 3, take belt off, rotate both cam wheels to match photo 1, refit belt and re-tension.

If the answer is 2, can I rotate the crank that small amount without rotating the ancillary pulley too?

[Will]

Chris;
For starters, you have the marks all mixed up- FIAT/Lancia motors have three marks on the crank pulley, they are :

10deg or 11deg BTDC (depends on motor)
This is the one you have marked as #1

5 degrees BTDC
This is the one you have marked as #3

And TDC - the one you have marked as #2.

So- you should turn the motor until your mark #2 is aligned (rotate clockwise to the last mark) and then set up the cams on the correct index marks- or as close as the belt teeth allow.

-Will
PS> you can also refer to the flywheel as seen in the bellhousing window- should have similar marks.

[SubGothius]

Holding a protractor up to Chris' crank pulley photo, those marks appear more like 10 degrees apart, rather than the 5 degree increments Will describes. I'm familiar with those 0-5-10 deg. marks; however, I've only seen them as reference marks outside the crank pulley, to which a single mark on the pulley itself would be aligned (e.g., 0-5-10 marks on the belt shield, or mine has a metal pointer similar to Chris' but with 3 points on it). I suspect Chris' center mark #3 may actually be his TDC, with the other two marking 10+/- degrees from TDC.

The references I've seen for the camcog timing, at least those comparable to your photos, all show the alignment holes tipped slightly inward (towards the center and each other) vis-a-vis the marks cast onto the camboxen -- note that Haynes has one photo showing how they got it not-quite-right on the first try, followed by a second photo showing how they got it right by going one-tooth-closer. Going by that maxim, it appears in both your camwheel photos that your intake cam may be one tooth away from proper sync with exhaust -- i.e., turn the intake cam one tooth towards the rear/exhaust direction while keeping the exhaust cam stationary, finesse as necessary to fit the belt, add salt and garnish to taste. :P :lol:

[Pope1]

This has all the makings of an interesting discussion.

Will, once upon a time I thought the same as you with respect to those marks. However, as Tye says, the spacings are way more than 5 degrees so that theory seems incorrect. I've checked with a couple of other VX owners and they reckon the centre line is TDC. In addition, here is a (poor) scan I made from my docs on setting the timing on an IE engine. Mine isn't an IE engine, but the marks I have seem to correspond to those in the docs especially if you look at photo 3. (The centre red mark in photo 2 is for illustrative purposes only and is not in exactly the right place).

http://home.caribsurf.com/chrysalis/images/timing.jpg

Using the IE theory, if I can call it that, mark 3 is TDC and mark 1 indicates maximum advance at 3200 rpm.

When all is said and done, my cam marks don't appear to line up with the crank at TDC. However, the two cam marks appear to be good relative to one another (photo 1) so, if possible, I am NOT inclined to change the timing of one cam relative to the other. Haynes only shows them a mere fraction out of alignment, we talking about 28 degrees at the crank here. The engine does run at the moment, but not quite as well as I think it should, and it pinks a bit in the mid-range with 9 degrees static advance and some octane booster in the tank. I'm inclined to set the cams where they should be, move the crank and try to refit the belt in that position. However, I'm not sure what the effect will be if I move the crank without moving the ancillary pulley. When the belt is back on, I was planning to take the plugs out and turn the engine by hand v e r y s l o w l y to make sure there are no internal collisions. Once again I am a little out of my depth (and the sole Lancia owner over here) so I'd be grateful for any thoughts on the desirability or otherwise of this course of action. Cheers.

[A1.6HPE]

Hello Chris,
A1.6HPE only has two markers on the crank pulley. However the guaranteed mark is the key/keyway in the nose of the crank. If you remove the big nut that holds on the pulley you will see the "notch". If you remove the pulley you will see the reference mark on the crankcase. It is as per the drawing that you posted. The key should be at 12 o'clock relative to the block base (ie the face that the sump fits against). With the Beta engine leaning backwards it is a bit awkward but if you remove the pulley that will make it easy to align. Also you can remove the spark plugs and probe for the peak movement with a screwdriver in cylinder 1 or 4 as you rotate the crank.
I have not mastered putting pictures in here so http://myweb.tiscali.co.uk/leocapaldi/tech/Beta_Crank_Pulley_1.jpg
has a picture of the situation on A1.6HPE - the camshaft marks line up very closely - I have never seen an engine that has the marks "perfect".

Leo
http://myweb.tiscali.co.uk/leocapaldi/tech/Beta_Crank_Pulley_1.jpg

[Wallace]

Best way to make sure is with a dial guage with its end stuck into a plug hole. You'll need to make up a something to clamp it, the magnetic ones don't stick to well to the ally head !. The "best" way is to mark the wheel either side of the "null" point by a fixed amount - then TDC is midpoint between these two marks.

[Pope1]

Hi Leo,

I really hope that I don't have to take the crank pulley nut off. I should be able to confirm TDC by your rod down a plug hole method. Actually tried that on my spare engine with a length of dowel, watched it come to the top and then looked at the crank to find... the damn metal pointer was missing from that engine. Will do that on the proper one tonight. I'll be shocked if it turns out to be mark 1 though, because that means that I have to have my static timing at about 15 degrees retarded for the engine to run properly.

I appreciate that the two cam wheel marks may not line up exactly but I was expecting to see something like photo 1 with the crank at TDC rather than photo 4. What do you think? The two cams appear to be perfectly aligned relative to one another and both appear to be off by the same amount relative to the crank. It's perhaps equal to one tooth on the belt. Is it worth trying to adjust the crank by one tooth (just by turning it with the belt off)?

[SubGothius]

When all is said and done, my cam marks don't appear to line up with the crank at TDC. However, the two cam marks appear to be good relative to one another (photo 1) so, if possible, I am NOT inclined to change the timing of one cam relative to the other.I still think your cams are one tooth apart from proper sync. Note your pics 3 and 4, where you show, respectively, the crank timed to the middle pulley mark (your mark #3) and corresponding cam alignment at that crank timing.

Looking strictly at your pic 4 now: your exhaust cam looks spot-on, but your intake cam looks rather wide of the mark; it appears to me that rotating the intake cam one tooth clockwise (as viewed in pic 4) would put it spot-on as well (just barely inside/right/rearward of the cambox mark), and in sync with the exhaust cam; if you compare where your intake cam mark is relative to the cog teeth, and figure where that mark would be if located one tooth over, you can see what I mean. Better yet, I just sketched up your pic a bit to show what I mean:
http://htdoctor.com/x/cars/Lancia/Zagato/cams2a.jpg

This is with the crank already at the middle/#3 TDC mark, so you only need to remove the belt, nudge the intake camcog one tooth back, refit the belt and retension. Not sure how precise the aux shaft/cog timing needs to be, or how that might(n't) affect dizzy/ign timing (assuming you have an aux-driven dizzy), but I doubt a mere tooth off or so would pose much if any interference risk -- a gentle hand-turn should confirm that well enough.

[Pope1]

Yep, see what you're saying Tye but I think it's to do with the angle of the shot, reducing the size etc because they both look off to the left on the car. Maybe I need to take a better shot of situation 4. Haven't moved anything so I should be able to go back and look again.

What about photo 1 though - don't they look pretty well synced there?

[SubGothius]

Yep, see what you're saying Tye but I think it's to do with the angle of the shot, reducing the size etc because they both look off to the left on the car. Maybe I need to take a better shot of situation 4. Haven't moved anything so I should be able to go back and look again.
What about photo 1 though - don't they look pretty well synced there?Mm, close, but not as good as pic 4 w/ one-tooth intake adjustment as I posted. Looking from the same vantage as both pics 1 and 4, in the references I've seen, the intake cog mark was slightly right/rearward of the cambox mark, whilst the exhaust cog was slightly left/forward of its cambox mark -- i.e., both cog marks tipped slightly together from their repsective camboxen marks, not both to the left or right of those marks.

[Pope1]

Yes, I've seen that arrangement in the Haynes book as well but I've not checked enough other cars to know whether that is normal or not. I'm going to have a look at car and the spare engine again right now and I'll get back to you in a little while.

[andybeta]

Best to start from scratch and find out where TDC is by seeing what mark is aligned when No1 piston is at TDC. Use a Maglite torch where you can focus the beam and rig a feeler that isn't going to disappear into the cylinder!! You might also be able look thorugh the viewing hole of the gearbox to see the mark on the flywheel or alterantively remove the back plate. A bit of hassle though. Then see how the inlet and exhaust cams sit and judge which if either you have to rotate. It can't be much.

The spacings of the marks on the crank pulley look too wide to be 5 deg intervals, more like 10 deg. The engine is timed at a round 10 deg up to 13 deg of advance. For sure I would turn it over a few times by hand and listen very carefully. For the auxillary shaft, was the lobe taken off it when the engine was fettled some years ago Chris? If so, you won't have a prob. You can even turn the engine over on the auxillary shaft pulley with a high torque drill if you can hold on to it.........

Then if all ok set fine adjustment of the iginition timing using a strobe timing light. Good luck.

Andy

[Will]

....sure you guys are right, I'd better stick to working off the flywheel like I'm supposed to! :P
The IE crank pulleys I have are different from yours BTW, but still not 10-5-TDC. Those are, as somebody pointed out, on the timing cover- but not on any of the the Beta IE covers I have- only on the gray plastic Abarth one.
Go figure!
-Will

[Pope1]

Put some paint on the marks and tried to put some paint inside the holes. Let's just say I had to do some editing in PaintShop Pro to clean up the mess. OK here we are. Yes, the inlet cam has moved further than the exhaust one but not by much. I still think that moving one cam relative to the other by one tooth will leave them more mis-aligned than they are now.

http://home.caribsurf.com/chrysalis/images/cams3.jpg

I'll check TDC as Andy and Leo have suggested and pop the cam covers off to see what's happening inside. Andy, don't know about the lobe I'm afraid.

[Pope1]

A bit tricky trying to judge which is the highest point even with marks on the length of dowel that I was using. As far as I could tell, the TDC position was actually slightly past mark 3 between marks 3 and 2! I marked the pulley and slackened off the bolts holding the pointer and moved it towards the mid line. There wasn't quite enough slack for it to get there but it moved closer. It was too late to do any more so I had to stop there.

Given my findings:

1. It explains the pinking. My current setting will be too advanced given the discrepancy in where I thought TDC was.

2. It begs the original question even more. Putting the crank at the TDC position has the cam wheel holes even further away from their pointers. In that respect I'm more inclined to agree with Tye now. It looks like the exhaust one could stay where it is and the inlet one should be moved back one tooth.

[Pope1]

One of the benefits of working from home is you can organise your tasks as you see fit. After lunch, I saw fit to adjust the ignition timing relative to my new TDC mark on the crank. The pinking has all but gone, just a trace here and there. Retarding another degree or two should take care of it.

Why is it that Lancias usually conspire to bring some bad news with the good? I've been holding off doing some other jobs until I got the engine running properly but today the car was telling me that I now need to overhaul the brakes and change the tyres. It wasn't a serious problem before but with the extra performance today it started to verge on the scary. To top it all, it's now blown a small hole in the transverse exhaust box and one section of it looks like it's been rotting and is in danger of falling out. I guess it might be time to souce a free-flow replacement in stainless perhaps, given that I bought that one second hand (but unused) only last year.

On the original timing wheel alignment issue, after thinking some more about how engines work, I've decided to leave it alone. It is possible (but is by no means certain) that the inlet valves may be opening a tad early but as long as they start opening after TDC when the piston is on the way back down, I don't think it's the end of the world.

Thanks one and all for your comments, suggestions and support. Back to work...

[SubGothius]

Sorry I've been away; my DSL's been cut off pending a move to a new(-to-me) apartment.

Re: finding TDC via the "dowel method", I just want to reiterate/restate/reinforce what someone was saying earlier to make things easier and clearer. To wit: mark the dowel or equivalent at some slight amount (say, 5-10mm) below TDC, and mark the crank pulley at the timing pointer when the piston rises to, and falls to, its sub-TDC mark on the dowel; the point on the crank pulley exactly between those two sub-TDC marks should indicate TDC.

[Pope1]

Thanks for that tip, it should make life a lot easier. Like all good ideas it leaves you wondering "why didn't I think of that at the time?"

[Tom McGaffigan]

It is always a good idea to check the accuracy of the timing marks, especially if the one on the clutch is the only one you have. IE Scorpion or Montecarlo. The timing mark on my Scorpion VX was 4 degrees off. I used a degree wheel on the crank and a positive stop that I made from an old spark plug to get it right. :twisted:
Tom McGaffigan

[Pope1]

Well in a perverse way that's reassuring Tom. I thought it was something peculiar to my car alone.