Extra timing marks on intake cam sprocket

everwiser · Post by **everwiser** » 19 Aug 2012, 18:16

I searched the forum but I didn't find my problem.

I have a '93 850 that the water pump failed on causing the timing belt to get loose and skip time. It looked like the marks I found were all still fairly close to right so I'm hoping pistons and valves didn't meet. I got everything back together but now the car won't start. Just to make sure I had the marks aligned correctly, I checked and rechecked and I found another pair of timing marks on the intake cam sprocket. They're about 30 degrees to the right of the mark I used to set my timing. One is dead center of a tooth valley and the other one parallel to the first and approximately 2mm to the right. It just about lines up with the left point of the tooth immediately to the right of the mark that centers the tooth cavity.

With the original marks lined up, this pair of marks sits somwhere between the 10 and 20 degree marks on my timing cover so it makes me think they're supposed to be there but I can't find anything on the web or this forum about these extra set of marks. Looking at everyone's pictures of their lined up timing marks, the cam bolts on mine look the same i.e. the exhaust cam has one bolt at 12 o'clock and the intake cam has one at 10 and 2. However, when cranking, it just doesn't sound right and it won't fire. If I give it a little gas while cranking it tries to fire but will backfire through the intake on occasion and just plain won't "catch". I'm tempted to try these marks instead of the one I used but 30 degrees is a long way to move the intake cam. If my valves didn't get smacked to begin with, I don't want to do it now...

This is not my first timing belt rodeo but it is for this car. Any help will be greatly appreciated.

Post by **rspi** » 19 Aug 2012, 20:08

If the water pump break made the car jump time, it's over. Then you hook everything back up and try to start it with it aligned with possible bad marks, that would finish it off.

Did you crank the motor over twice by hand before you tried to start it? You can always double check the timing by pulling the camshaft sensor and distributor.

Last statement... do a compression test.

Post by **Ozark Lee** » 19 Aug 2012, 21:32

Snap a picture of your camshaft pulleys and post them back. We may be able to identify the correct marks.

Push comes to shove you can take off the cam position sensor and the distributor and set the camshaft timing based on the slots on the back of the camshafts.

RSPI is right though, it would be quite the lucky event if the water pump failed and the valves didn't get smashed.

...Lee

everwiser · Post by **everwiser** » 20 Aug 2012, 18:03

Not to be "sensitive" or anything but I'm not some snot-nosed newb who blew his car up and is hoping for a miracle. I've been working on my own cars since my first one in 1981 so save the doom and gloom pronouncements for someone else. I'm fully aware of what an "interference" engine is and what happens when the timing jumps. I put a water pump and a timing belt on it so I can determine what I'm working with; not a part more than is needed at present. If you don't have information pertaining to my question about multiple marks on the intake cam sprocket, save your fingers the extra typing by refraining from telling me what I already know. Please and Thank You.

If you look close, you'll see the mark I used pretty close to aligned with the notch in the timing cover and the two mystery marks just shy of twelve o'clock.

The next two just shows you both cam sprockets with the marks fairly close. I say fairly because I've already taken the tensioner pusher off and the belt is less than tight right now.

Has anyone seen this before?

Post by **Ozark Lee** » 20 Aug 2012, 19:29

The real marks are the ones that are actually cut into the sprocket rather than the Sharpie marks. On the first picture you look a full tooth off on the intake sprocket. On the last picture you look OK as far as cam timing goes so long as the crank is lined up. Are the cam sprocket bolts in the center of the slots or did you take the bolts off? The only time I remove the cam sprockets is when I change the seals or as a part of a head gasket replacement.

...Lee

everwiser · Post by **everwiser** » 20 Aug 2012, 20:19

The first picture is the same as the others but at a different angle which is why it looks off. Neither cam sprocket has been removed and all bolts are tight.

Those aren't sharpie marks. I did sand the edge of the sprocket to highlight the marks but they are stamped in the sprocket just like the others. They are the same width and depth. They look like they were factory stamped. I didn't post a picture of it but the crankshaft sprocket mark is lined up with the mark on the block. The mark on my crank sprocket is the small "v" notch in the valley between two teeth.

I know it's got compression because I've felt it when I was turning the crankshaft with my socket wrench so I could verify the marks were lined up after two rotations; they were. I've since turned it several more revolutions looking to make sure I've identified/verified all the marks so trust me when I say it's got good compression. The crank sprocket has a single mark and so does the exhaust sprocket but the intake sprocket has three with two so close together as to be one.

I don't get home from work until 6-ish so I don't do anything I don't have to on weekdays. I'm going to let it sit until Saturday before I work on it again. I'm hoping someone else has ran into this before and can offer some insight/advice.

Post by **rspi** » 20 Aug 2012, 20:47

You can always double check the timing by pulling the camshaft sensor and distributor.

Last statement... do a compression test.

Post by **erikv11** » 20 Aug 2012, 20:51

Those markings are unusual. I'd just pull the distributor cap and the little metal adapter underneath the rotor, to eyeball the end of the cam. If the slot is horizontal, then you have the correct mark. It will be both crystal clear and easy.

Does the car have a turbo? That would make pulling the cap a bit more cumbersome, I suppose.

EDIT: rspi beat me to it, same post ...

everwiser · Post by **everwiser** » 21 Aug 2012, 06:12

No turbo. I did remove the distributor cap to clean up the electrodes but I didn't remove the rotor. The rotor was pointing towards the front of the car slightly above 'level', if that means anything. I'll go deeper this weekend.

everwiser · Post by **everwiser** » 25 Aug 2012, 15:51

Long story short, I had the correct marks to begin with. I pulled the distributor and cam sensor and both slots were horizontal on my originally used marks. I got it to start but I've got at least two bum cylinders. One sounds like the intakes and the other like the exhausts. Oh well. Now to decide on putting more money into it or parting it out...