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Discussion Starter · #1 ·
Hello all.
First time posting on the forum but I've visited often and love all the info and advice!
I'm by no means a professional mechanic but I like to get in there and do the job myself when possible.

So my issue:
I just finished replacing the timing belt with new tensioner and roller.
This was the 2nd time I've done this job to this car and the first time it went great.
I set the marks on the old belt and sprockets and then copied those marks on to my new belt and re-installed.
I did the two rotations to listen and check everything.

Put the car back together and it started, ran and idled perfectly and I drove it home (20min drive) to a nice warm garage where she sat for 3 days or so.

This morning I jumped in the car and now it won't turn over.
I had a problem with the battery previously so I replaced that but no change, won't turn over.

When I was doing the manual two rotations and checking the TDC marks I did notice that the cam and crank TDC marks were not aligning and that the crank was about 1 inch ahead of it's mark when the cam was on.

As the marks on the belts and sprockets all matched up I didn't think it was an issue. Could be a huge noob mistake after reading about interference engines and bent valves etc.

So I'm thinking to crack it back open and reset the timing.
I can't seem to find clear instructions on resetting these though if they don't line up.
Can I turn these independently of each other to get them where they need to be or what's the best procedure?
I've scoured through the forums and believe I should just set the crank and then turn the cam on it's own.

Thanks in advance for any advice!
 

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When I was doing the manual two rotations and checking the TDC marks I did notice that the cam and crank TDC marks were not aligning and that the crank was about 1 inch ahead of it's mark when the cam was on.
Obviously the bolded word is a typo/mental error; you probably really meant "...the cam sprocket timing mark was one tooth ahead of the crank sprocket timing mark...".

If so, this is normal. After the timing belt gets to 25-50 percent of it's useful life, the belt will have stretched a bit (~one tooth). This stretching of the belt allows the cam timing mark to eventually match the crank timing mark.

In any event, a properly installed 1.8T timing belt should have the camshaft pulley timing mark align with the head just before (~one tooth) the crank pulley aligns with its timing mark on the TB cover while the crank is being turned manually (clockwise).

Good Luck
 

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Discussion Starter · #3 ·
Thanks for the quick reply Electron Man

Unfortunately not a typo here's an illustration to show where my crank mark is when the cam is TDC (cranked manually):
my-timing.jpg

So I'm going to go in again and attempt to reset but I'm still not 100% sure on the best way to reset these to get them back to where they need to be.

The closest I found to clear instructions on reseting with the belt off was from this site - How do you find TDC on a 1.8T (assume timing belt is off).

If the cam is significantly out of time and require a good deal of moving I would find TDC and then back it off about 20 degrees or so, so NO piston is at TDC. When turning the crank or cam, do so gently, if you come up against resistance stop and turn the other shaft.
Any advice is greatly appreciated!
 

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Well it seems way off but to me that should not stop it from turning over. When I lost oil pressure and my cam gear key sheared causing all the exhaust valves to get bent, the engine still turned over. It sounded wierd, because it had no compression, but it cranked and cranked.

When you put the crank on it's TDC mark, how far off is the cam?
 

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Discussion Starter · #5 ·
Hey Woody - Thanks for Chiming in!

Yeah it was weird to me that it turned over, sounded great, idled great and I drove home fine, but then after a couple days sitting nothing.

The first attempt I had at turning it over after it sat a couple days it almost went but then just petered out and now it's just turning and turning.

Just went out to the garage and gave it a another quick turn over and same as before it almost caught the first time after sitting the night and then nothing again.

I popped the rad into service position quickly to dig back in and noticed the spark plugs smelled heavily of gas, guessing it got flooded trying to turn it over?
I only tried to turn it over 3 times.
Not sure if that's a clue?

I set the crank at TDC and did 2 rotations noting where the cam was at:

Cam-Positions.jpg

Basically one tooth ahead on the first if you were to draw a line straight down from TDC on the cam sprocket and one tooth behind on the second rotation.
 

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You're only one tooth off - cam timing just a tad (one tooth) retarded. That explains why it cranked and drove fine 3-4 days ago.

Might've happened when you were taking up the slack on the left side of the belt so that the belt's where it needs to be just before pulling the tensioner "pin". I actually held the belt where I wanted it and had a helper pull the pin.

Again, Good Luck
 

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Discussion Starter · #7 ·
Wheww - Ok so I should be ok in regards to any valve type damage then?
I will still attempt fixing that to get it dead on but now the new hunt begins why won't it turn over?

I did give my spark plugs a clean the first time I had them out with alcohol and a brass brush.
Wonder if I should just go ahead and replace those?
 

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Yeah, you should be able to adjust that fine. I thought you initially said it was not turning over. It sounds like it was turning but not firing.

When mine crapped out the cam gear was about 5 teeth off and it still cranked, just sounded like an air compressor...lol

Good luck resetting it!
 

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Discussion Starter · #9 ·
My bad - I'm a web developer more than a mechanic so I easily confuse terminology.

Yeah it's turning over but not starting or firing.

I can tell it's getting fuel, can here the pump before turning the key fully and as mentioned there's gas in the engine.
Will have a stab at resetting the belt in the morning, also been poking around on the forums a lot today and I see a lot of folks mentioning just keeping your foot right down on the gas while trying to start.

I've also left the ground cable off for the night.

After all of that if still no love I'll start going through the checklist of sensors and wires I may have disrupted.

Cheers
 

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Your valve timing is about one tooth retarded, with a new belt it should be set advanced less than one tooth.
Turn the crank to TDC, then adjust the cam to correct timing.

One tooth out would not cause it to turn over without starting.
It might help if you get it scanned and post the codes.


Your starting issue could be due to flooding, try the following procedure.
1. Remove the fuel pump fuse #28, and remove the plugs.
2. Crank for at least 20 seconds. (With accelerator pedal held to the floor)
3. Put 5 to 10 mils of engine oil in each cylinder through the plug holes.
4. Crank at least 10 seconds.
5. Refit the plugs and try to start. If there is any firing, continue until it no longer fires.
6. Re-fit the fuel pump fuse #28, and start the engine.

NOTE: You may need to crank multiple times, 10 - 15 seconds each time.
 

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Discussion Starter · #11 ·
Thanks for that Tomvw!
Will give it a try first thing in the morning!

Any advice on the best/easiest way to adjust that cam to the correct timing?
Or is it just the same as installing?
1. Mark the belt and sprockets
2. Remove Tensioner
3. Removing the belt
4. Reset the cam forward a couple teeth? (Can I just put a wrench on this and turn it?)
5. Put belt on
6. Test
7. Release tension

Cheers

Edit - Will get it scanned if I can get it running long enough to make it to the shop
 

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The only timing marks you will need, were put on during production.
While the crank is at TDC and once the TB is removed from the cam pulley, you can use a wrench to turn the pulley to the correct timing.
Do not turn the cam to more than 2 teeth from TDC. (Valves in cylinder 4 could be damaged)
Re-fit the TB, and tension as per TB replacement.
 

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Discussion Starter · #14 ·
Want to throw out a big thank you to everyone who offered me some assistance!
I adjusted the timing and now it's lining up nicely with the cam about 3/4 - 1/2 a tooth advanced of TDC.

Thanks so much on the flooding instructions Tomvw!
Worked a treat and it fired up instantly first try after following your steps, and again an hour later just to be sure.

Not all tropical beaches and bikinis just yet though, there is a ticking noise coming from under the valve cover.
Really don't remember hearing it before but I may have not been so paranoid about damage.

I took a video for sound.



Would appreciate a couple sets of ears on it to see if it's anything I should be overly worried about before putting the front end back together.
I will take her into the shop ASAP and get a read out of codes.
I watched a couple videos on bent valves and they sounded much worse than mine but as I'm a paranoid noob appreciate any info!

Cheers
 

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Can't be sure from video, but it sounds like the cam chain.
Did you set the TB tension correctly ?
Is the tensioner damper working properly ?
Is the oil pressure within specs ?
 

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Discussion Starter · #16 ·
Cam Chain sounds like it might be the cause as that seems to be where the sound is coming from more or less.
I also noticed when I fired her up cold this morning there was no sound but after idling for a little bit it slowly started coming back.

The tension dampener seems to be doing the trick. It was a new one but I did take it off and slowly compress it again in a vice when I made my last adjustment.
Oil Pressure seems ok although I don't have the tools to test properly.

If anything I'd say there might be a little too much slack from the top cam sprocket to the intermediate sprocket.
Must have been from when I adjusting that cam sprocket.

Can I just wrench the intermediate ahead a bit with a wrench on the cam holding it in place with the belt still on?
 

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STOP ! Do NOT crank the engine.

If the belt is properly tensioned in one area, it will have about the same tension everywhere else.
You obviously have no understanding of the cam drive system, if you haven't already done serious damage you are lucky.
This is not a job that can be safely done by trial and error. I suggest you get it checked by an experienced person.
Either get it towed to their shop, or have them come to you.
 

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Discussion Starter · #18 ·
So quick update on my Passat saga.

I had one last go at adjusting the tension on the belt and it's 100% consistent now all the way around and staying at TDC (cam slightly advanced under a tooth)

I then called in my mechanic buddy who brought the tools to do some tests on compression and pressure but after giving it a listen he said I'm just being paranoid and everything sounded a-ok to him.

He said if anything it sounded like the injectors were a little louder than normal but nothing to be overly concerned about.

Again big thanks to everyone for the advice and suggestions!
 
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