Camshaft and TDC on flywheel WAY OFF

[86jetta1.6]

I picked up a '88 Jetta 1.6 NA with supposedly a '81 engine in it. At the guys house he said it had glow plug issues so it was difficult to start unless you push start it. Which we did so I could drive it home. Seemed to run pretty decent on way home. So I pulled all the glow plugs, replaced a few nonworking ones, and ran individual 10ga wires to each glow plug along with adding a solenoid and 6 gauge wire directly to battery and I also added a manual switch on the dash. Car still started pretty hard. Took it for a drive, ran about 12 miles then the engine seemed to "runaway". Key wouldn't shut it off but pinching the fuel feed line did. After restartting it several times, it ran off immediately everytime, but on restarts the key shut it off everytime. I searched these forums and decided to try another IP that I had access to off another running 1.6. Here is where it gets wierd.....

I pulled the plug on the bellhousing to line up TDC on fly wheel. Easy enough.... however, when the mark on the flywheel is lined up, the camshaft slot looked like this
http://www.flickr.com/photos/114225106@N07/11912412954/



Any thoughts?
I spun the motor until the cam lined up and the first lobes were both up and the IP marks lined up as they should, but then had nothing on the flywheel. When I had the flywheel so that the marks lined up I marked the front pulley so I could see how far off I was. I marked the pulley so the yellow line was straight up. When i lined up the cam and IP where they should be the pulley looked like this.



http://www.flickr.com/photos/114225106@N07/11912219373/

Looks to me like its about 110 or 115 degrees off of being straight up.

So now I want to replace the IP, do i leave this timing as it is? Put the new IP on and see how it runs or do I address this now? Can i remove the timing belt and somehow get the crank to line up? I'm worried if I take off the timing belt and try to turn the crank I wont be able to get it where it needs to be because of interference. I am very lost. Any input would be appreciated

[82vdub]

Ok, a couple things. Your flywheel may be 120 degrees off. However, don't fret, because you can determine TDC without using the inspection hole in the trans bellhousing.

The pic of the front pully has the crank just a bit past TDC. You can search for a post with pics on finding TDC by the front pully (or here viewtopic.php?f=8&t=11019&p=76009 ). Basically, with the front pully, the two bolts must line up with the centerline of the cylinder, and that dimple in the pully is at the 7.5 o'clock position. As you look at your pic, the two bolts are a little past (crank rotation) having them going straight up the cylinder centerline, so it's too far advanced.

Once you find proper TDC, you can then set the IP and cam timing as you would and then adjust final timing of the engine after it's initial setup. Make sure you rotate the engine at least two revolutions with a wrench on the crank before using the key after messing with the timing belt. Any metal to metal or hard clunk, and you've got interferrence somewhere with the pistons and valves. You can correct this timing, you just need to find TDC.

On your post on runaway, the inlet vanes of the IP that was on the car may be stuck, leading the IP to suck as much fuel as it can and that leads to the high RPM's that you were able to shut off with the key.

[86jetta1.6]

Ok, Question 1, Are the inlet vanes servicable in the car? I have not removed the IP yet, but I do have the cover off, should I continue to swap IP's or is there a way to correct this in the car? I will also search the forums on this topic.

[86jetta1.6]

Ok, I think I understand what you mean with crank pulley. However, I am not sure with this method how to get it exact, it appears that my system is slightly off. In this photo I put the cam lock in and feeler guages on both sides to lock cam. This picture is what the crank picture looks like. While it appears the dimple is at 120 degree if the cylinder was perpindicular to the ground, but it is not, the cylinders "lean" back to the firewall. Do I mess with this now? Or is it close enough? I'm afraid to mess with it without having a flywheel mark to get exact TDC on........

[86jetta1.6]

I am trying to proceed, I have the other IP bolted up loosely. It seems like I really need a precise TDC mark for setting the pump timing as well. I guess I can use the marks on the ip and just watch the slot in the back of the cam for reference. Does that sound right?

[TylerDurden]

You can determine TDC with a piece of clear tubing and a bit of ATF:



The tube goes in the injector or glowplug hole. TDC is fluid at the highest point.

[82vdub]

Ok, I think I understand what you mean with crank pulley. However, I am not sure with this method how to get it exact, it appears that my system is slightly off. In this photo I put the cam lock in and feeler guages on both sides to lock cam. This picture is what the crank picture looks like. While it appears the dimple is at 120 degree if the cylinder was perpindicular to the ground, but it is not, the cylinders "lean" back to the firewall. Do I mess with this now? Or is it close enough? I'm afraid to mess with it without having a flywheel mark to get exact TDC on........

This is what I mean when I said that the crank is just a little past TDC. The engine block is tilted at an angle towards the inside of the car, so you would need to rotate the crankshaft counter clockwise until those bolts line straight up the line of the cylinder. To be absolutely sure how close or far off you are, make sure you rotate the crank with a wrench on the crank bolt before using the key. These are interference engines and you can bend valves if you assume all is fine and just use the key.

So, rotate the crankshaft counter clockwise just a tad, set the IP line on the back of the sprocket with the line on the IP bracket locked with the pin, and put the lock bar in the cam. You're 95% done with timing at that point.

I am trying to proceed, I have the other IP bolted up loosely. It seems like I really need a precise TDC mark for setting the pump timing as well. I guess I can use the marks on the ip and just watch the slot in the back of the cam for reference. Does that sound right?

You should take the time to get TDC as best you can determine before proceeding. The timing is critical, but if you eyeball the bolts lining up with the centerline of the cylinder, you should be within a degree or two.

[86jetta1.6]

Ok, I was able to get the car running enough to take it around the block, but clearly it needs some more fine tuning. I am pleased with my progress but I will definitely back track another day and try and get my crank timing a little closer to correct. Obviously the run away condition was in the IP as suspected, the car no longer has that issue. I timed the IP by ear as best I could just to hear it run. I bought this car as a donor body for my 86 jetta that is severely rotten. I planned on putting my 1.6 in it if need be but if I don't need to that would be even better. With the car running tonight there seems to be a lot of blowby coming out of the valve cover breather. I think this motor may be done for now, seeing that tonight makes me think I really shouldn't mess with it anymore and I should just put my known good motor in it. Once out, I can tear it down and possibly rebuild it and then obviously put the flywheel on correctly. Today's goal was to get it running to see make a decision whether to keep this motor or put my other one in. Looks like I will be swapping motor due to the amount of blowby. Blowby doesn't lie right? I assume the motor needs rings and/or general overhaul. I was told that it only has 75,000 miles on it but the way she runs I assume it has more than my good one at 220,000. Is there anything else that can cause blowby? I assume there is no way that is timing related.

[TylerDurden]

These rigs usually have a bit of blowby, plus the later style vacuum pump pushes air into the crankcase (not likely on an 81 but it might have been upgraded).

I'd get compression numbers on all holes before ripping it out... above 300 and I'd probably run it.

[86jetta1.6]

Sounds good, I will order some parts to do a compression check. I think I will give it one more day of messing around. I think I will start by trying to eyeball the crank-cam timing as described above by 82vdub to get it closer to correct. I'll also try to get the comp test done before making a final decision. It seemed to run ok tonight, it certainly starts easier than it did in the past. I am learning a lot today, thanks for the input!

[86jetta1.6]

I have never had one of these flywheels off. Did somebody just bolt the flywheel on incorrectly? I assume at 120 degrees it will bolt up as is the case on my car. Should I consider pulling the motor to remove and rebolt the flywheel to the crank so I don't have this issue? Not that I really want to but I wouldn't mind the experience of pulling one of these. Maybe I will do my motor swap as planned, put the good motor I have in this car. Then put the questionable motor back in my car with the rotten floors and try and get it running well in that car. During the swap I will correct the flywheel.

[TylerDurden]

I'm not confident that the eyeball on the crank pulley gets close enough, for me anyway. It doesn't take much error to have the valves hit the pistons.

The tube gag is quite accurate (the thinner the tube the more accurate)... I'd just mark TDC on the flywheel. The flywheel might be from a gasser or had lightening done that obliterated the TDC mark.

Factory mark should be something like this:

[86jetta1.6]

The factory mark is definitely there, I have seen it, its just not in the right spot. Appears to be approx 120 degrees off TDC

[86jetta1.6]

I would like to try the tube suggestion, I guess I just need to find a nipple to thread into the glowplug hole to attach the tube to, is that how it is attached? I have a glow plug with the exterior end broke off and it looks hollow, maybe if i cut off the interior end I could attach that to a tube as long as I can blow through it to make sure there is a passage?

[82vdub]

I discovered the crank pully indicator for TDC when I discovered that my flywheel was off by 120 degrees when I had a mechanic service things previously. Some have said that you can't put a flywheel on 120 degrees out as they are pinned differently, but clearly mine was and so is yours.

I think that there's enough slop in the timing belt to where the crank being 100% at TDC isn't as crucial as it may seem. Plus, when you think about it, a couple degrees before and after TDC that piston is moving ever so little. Just be sure to rotate the engine to make sure there's no interference before starting, and if you start, then make sure there isn't any noise.

The other methods of finding TDC are not as exact as having a specific mark that's pretty accurate - like the mark on the flywheel. So, which alterior method is more accurate? Good question.