Distributor rotor install help.

[MakeshftPatriot]

I have been rebuilding my car all winter since a previous accident. My distributor cap and rotor were crushed beyond recognition. I have since bought a whole new ignition system with rotor and cap, unfortunately there weren't enough remains of the rotor left to recognize what angle it was at.

I put the first cylinder as high as it can go and installed the rotor to where I believe it makes sense according to the firing order and distributor cap. I wanted to get feedback before I try and start it, if the rotor is off place, its grounds for disaster correct? I also have a feeling it needs to be one right of where its at.

Here is a picture, I hope you guys can help me get this right.

[1987944Sick]

i think when at TDC the rotor should be pointing right/down side

[MakeshftPatriot]

Is there any way to be certain your at TDC? Should it simply just be at the "Five o'clock" position from what I have now? I'm as TDC as I can understand.

Anyone know what can happen if its wrong?

[mikepellegrini]

I believe there's an indent (hole) in the camshaft where the rotor's hex head locking screw will sit. The rotor should only fit on in one place.

As long as the camshaft is properly lined up and the crank is on TDC, you're okay even if the rotor was on in the wrong place - the car just wouldn't run.

I wouldn't trust the dowels in the spark plug holes to ascertain TDC - you oughta check the timing mark on the flywheel (looking through the inspection port by the speed/ref sensors - you oughta see "OT").

When the crank is on TDC, the mark on the camshaft gear should line up with the mark on the back belt cover (I think it's in about the 2 o'clock position relative to the camshaft gear). The marks on the balance shafts should also line up with their belt cover marks.

If all you did was change the distributor cap (and the belts were never taken off) then you're in the clear anyway.

Here's the write-up at Clark's on finding TDC - http://www.clarks-garage.com/shop-manual/eng-13.htm

[1987944Sick]

Originally Posted by MakeshftPatriot

Is there any way to be certain your at TDC?

yes,there a window on the clutch housing..it kinda hard to see first time,u have to look at angle...clarks garage had lots of info..http://www.clarks-garage.com/ go on garage shop manual and look it up by T letter..

[1987944Sick]

i just posted the same thing

[MakeshftPatriot]

I haven't touched the belts at all, but my buddy said the impact could have made the cam belt jump teeth if it wanted to turn over with the rotor smashed into it. Is that possible? There is no sign of damage on the belt when I turn it over so I don't think that's an issue.

The help is greatly appreciated. I forget what the engine sounds like!

You're positive the rotor needs to point down and right once at TDC?

[Techno Duck]

At TDC, the rotor should point between the 4:00 and 5:00 position.

The best way to verify you are at the correct TDC and not on another stroke other than the start of intake is too remove the belt covers and line up the marks on the cam gear and cam cover. These should correspond with the OT mark on the flywheel.

[TibetanT]

Mike and Jon are correct! The rotor sits on the shaft and there is a tiny screw that fits to hold the rotor to the shaft. Rotor can only go on one way properly with the screw.
On the flywheel, OT should be seen looking into the inspection hole. Just behind the reference sensors.
On the cam cover, just above the spot where the rotor and cap sit, there is another inspection hole with an arrow which points to the mark on the cam. (A slit in the teeth of the cam is the mark to line up with at TDC.) All of these should be lined up, as well as the balance shaft belt pulleys lining up with the marks on the back cover...you will have to remove the front covers to the belt housing to see them.

As far as the cylinders and pistons placement, the only one you are worried about right now is cylinder number 1. The closest cylinder to the front of the car.

[MakeshftPatriot]

So I tried aligning it up today and here is what troubled me.

I line up the line on the cam gear with the window but I can't find the OT on the flywheel they describe in the article.



That's what I see, and if I turn it forward or back I cant find the OT at all. Guess I need to dig deeper.


EDIT: Found a line on the flywheel with out the OT, but the pistons do not appear to be at TDC at all.

When the line is here (as close as I could get for a one man job).....


The pistons look like this when the line on the flywheel is centered, and the cam gear isn't lined up at all.


I didn't touch the belts at all, but could the accident made it jump teeth? Is my flywheel installed wrong haha?

I lined up the cam gear as said in the article, and the rotor fit in between 3 and 4 o'clock like said but the flywheel alignment is way off. I have a hunch I'm probably missing something key in this equation, hopefully its a no-brainer.

[mikepellegrini]

When the mark in the flywheel window is in position, the mark on the camshaft gear should also line up.

I suppose if the impact suddenly mooshed the distributor/rotor - completely stopping it - then yeah, the force of the engine running could have stripped a few teeth off the belt. All of the engine torque would have suddenly been applied to the belt as the rotor abruptly stopped. That's a lot of force.

What was the engine doing when the impact occurred? Revving? Idling? Did it stop running immediately? If it was high RPM's when the impact happened, that'd mean even more torque to the belt.

You probably oughta pull the belt covers off and look. You can check the marks on your balance shaft pullies then as well - if the belt stripped/jumpped teeth, they will be off too.

If the marks do not all line up, I'd put on new belts - I wouldn't trust the old ones if they did slip/strip. Belts are cheap - head jobs are not.

From Clark's - Cambelt removal: http://www.clarks-garage.com/shop-manual/eng-05.htm

Installation: http://www.clarks-garage.com/shop-manual/eng-06.htm

Tensioning: http://www.clarks-garage.com/shop-manual/eng-10.htm

Your timing marks should all line up.

[callmethewander]

Did it look something like this?



It took me about a year and a half but I just put it back on the road last week, still needs a little more paint work! Hang in there, it will be worth it. I don't know about the timing, but my cap and rotor was also smashed beyond recognition, the new one went on without a problem, It sounds like you have to really check yours out tho. Definetely check out those links to clark's garage, great info there!

[callmethewander]

Sorry, also make sure you're looking at an S2, it may be different as far as the rotor position from an 8 valve engine, I don't know.

[MakeshftPatriot]

I dumped the clutch right before I tagged the rear under guard of a semi, got cut off by a woman on her cell phone. The car was still idling fine as I pulled to the side of the road I killed the engine before I came to a stop fearing something could be sucked in. I was very surprised it was still running with the smashed distributor and rotor.

Wander, the damage is exactly as yours, my passenger fender wall is getting a trim from the fender being smashed into it.

Mike, There is no damage whatsoever on the timing belt. When I have the cam gear set to TDC the lines on the crankshaft pulley point to the distributor. If I recall reading correctly that is where it should point? I was unclear by what you meant about lining the pulleys up.

[Techno Duck]

I agree with Mike, take the belt covers off and line up everything at TDC based on the mark with the cam gear. The balance shaft sprockets have marks on them also that correspond with markings on the rear belt cover to designate TDC. Basically i want to see if the cam gear is still lined up correctly with the balance shafts. If they are, i dont think the belt slipped.

As for the flywheel markings, the line you took a picture of looks to be the correct one. The OT marking will be visible by turning the engine slightly CCW (only a few degrees) if looking at it from the front of the car. To verify if the flywheel is at TDC, there is a notch visible from under the car in an opening to the clutch housing, right by the starter. The notch on the flywheel should roughly lineup with the notch on the clutch housing.

BTW, i have some limited experience working on my friends 968 which uses the same style ignition rotor. Its been a while since i worked on it, but i am almost 100% sure the ignition rotor is basically keyed so it can only go on the cam gear one way. With what you said about the ignition rotor pointing in the 4:00 position with the cam gear at TDC and looking at the pictures, i think your crank and cam are out of time with eachother. This unfortunately means piston / valve collision may have occurred. I am very surprised the engine still ran if the cap and rotor were destroyed as you mentioned.

[mikepellegrini]

+1 what Jon said. Based on what you said about the distributor being smashed, I'm surprised the car ran at all.

I'm not sure what you're talking about with the green marks on the crank pulley.

The only 100% accurate way I am aware of to set the car OT is to use the window on the bellhousing just in back of the speed/ref sensors (I've read there is a inspection port on the flywheel somewhere down by the clutch slave where you can look but I've never used that).

The balance shaft sprockets have marks on them (small notches that look like "V's") which you line up with markers on the back belt case. Here's a picture of an icky looking lower balance shaft sprocket on an 84 NA:



Note the plastic marker tab on the case and the notch in the backside of the sprocket. I've never seen the guts of a 3.0 L but I'm guessing if this isn't exactly the same, then it's very close to what you have.

The upper balance shaft sprocket has the same thing. I don't remember what position the plastic marker tab is in on the upper BS,

When the crank is OT and the camshaft gear is lined up on it's mark, then the two BS sprockets must also be lined up on their markers.

If when the crank is lined up OT and the markers on the cam and BS's do not line up, then you've got problems.

You car ran until you turned it off and that's very encouraging.

If the marks do not all line up, then like I said, I'd re-do the belts - line up everything correctly and slap new belts on. Just to be safe.

[TibetanT]

Hey Guys:

I just had a thought...I know don't laugh.

Anyway, I just noticed we are talking about a 1991 944S2, right? Well, they have timing chains that move the cam. Maybe, the timing chain is not moving the cams properly?? These are 16 valve engines right? With two cams OH, so maybe one of the chains slipped on impact. There are plastic type pieces under the chain that they ride on, which may have failed.

Hope I am wrong about this though, since it is probably not a good thing. But, if my memory serves me right, this car 3.0L does have a timing chain in it.

Like I said...just a thought.

[Mericet]

This thread might be helpful as well: Quick question: 944S distributor rotor

[bazar01]

Here is a link and look at the last image on page 2. The rotor points to #1 at TDC.

http://clarks-garage.com/phpBB2/viewtopic.php?t=6122&postdays=0&postorder=asc&highlight=cam+chain+tensioner&start=15

[Techno Duck]

With the thead Mericet posted, it looks like the rotor on the 16v S actually points in the 10:00 position with the cam gear set to TDC? I retract my statement that the rotor points in the 4:00 position, i forgot the design of the distributor cap on the 16v engines is different, all of the ignition wires plug onto one side, unlike the 8v caps where everything plugs onto the front. Sorry for the confusion!!!

So with the cam gear lined up with the TDC mark on the rear cam cover, does the rotor point 10:00? In the very first picture you posted it actually looks correct with the #1 cylinder at its highest point and the rotor pointing at 10:00... this is assuming the cam gear is set to TDC based on mark with the rear cam gear cover. At this point you should see the OT mark in the bellhousing window. If you dont, i would pull the belt covers off and verify the location of the balance shafts. However based on that first picture, it looks like everything is right. Again, really sorry for adding to the confusion of this thread!!