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JensenB
01-10-2011, 06:35 PM
So I fired up my engine (12V v6) after my swap and timing belt service and it's making a ticking noise that increases with rpm and sounds like its primarily coming from the psgr side valvetrain area. Not throwing any codes either? My process of the TB service was that I had the perfectly running when pulled motor on a stand, aligned at TDC, and marked the old belt and sprockets. The cams were straight across, and I simply marked the old belt and transferred ink to new belt, checked, re-checked then re-checked after installed. The cams again were straight across and the crank was unturned because I had a dowel holding the crank from ANY movement. My TB tensioner is tightened as per the fsm (the belt can be JUST turned 90deg with 2 fingers...) WHO'S GOT SOME IDEAS?

-I've turned the motor over by hand right after the TB install and there seemed to be no noise or valve contact?
-Oil level is right up there..

JensenB
01-10-2011, 07:02 PM
After re-reading my shitty copy of the fsm, it appears that I should have loosened the cam sprockets and then held them straight with a specialty tool instead of just transferring the marks across???

walky_talky20
01-10-2011, 07:26 PM
That isn't necessary. Just marking the sprockets is perfectly fine. If it was in time before, and you got the marks transfered properly to the new belt, you're fine.

You don't need the special tool unless you are changing the cam seals, where you have to remove the sprockets.

As for the ticking, it's hard to say. Can you locate it more specifically using a screwdriver to the ear?

JensenB
01-10-2011, 07:50 PM
Well, I did briefly use a mechanic stethoscope and it sounded like it was coming from the lifters or valves on the passenger side? Or could be a valve not closing/opening at a proper time? I will seafoam the oil soon to see if clears anything up. Why does the fsm call for loosening the cam sprockets and THEN using specialty cam locking tool??

Ldiaz12
01-10-2011, 08:20 PM
If you don't Pop your cam Sprockets you won't have even tension around the whole belt, its good to use the Cam Locking Bar for this so when popping the cam sprockets so you dont loose timing.

JensenB
01-10-2011, 08:57 PM
All my marks on the new belt lined up without a hassle during install. I will have to re triple-check my timing using the balancer markings when it warms up out there, it's been around -30C past few days!

walky_talky20
01-11-2011, 12:02 AM
The reason for loosening the cam sprockets (and them not having a key-way) is to adjust the timing more exactly when changing the belt. This is more important on a very long timing belt as there can be some variance between belt manufacturer, etc. But if you get a good quality belt, like Conti-Tech, it really isn't an issue. And in any case, the belt will stretch over time anyway, and nobody is going in halfway through the belt interval to adjust that, are they.

In actuality, leaving the cam sprockets set where the factory put them is probably your best bet. Do you think anybody in their garage with some aftermarket cam lock tool is going to get them set more accurately than the factory did? Nope, probably not. But that's just IMHO.

Ldiaz12
01-11-2011, 05:33 AM
The reason for loosening the cam sprockets (and them not having a key-way) is to adjust the timing more exactly when changing the belt. This is more important on a very long timing belt as there can be some variance between belt manufacturer, etc. But if you get a good quality belt, like Conti-Tech, it really isn't an issue. And in any case, the belt will stretch over time anyway, and nobody is going in halfway through the belt interval to adjust that, are they.

In actuality, leaving the cam sprockets set where the factory put them is probably your best bet. Do you think anybody in their garage with some aftermarket cam lock tool is going to get them set more accurately than the factory did? Nope, probably not. But that's just IMHO.

But the position of the sprockets isn't relevant to the position of the position of the Cam shafts. The procedure of Popping out the cam gears is to have even tension around the belt. It's just the correct way to do the Timing belt, Having uneven tension around the belt could cause off timing in one of the banks. Im not making up my own stuff.
here are the instructions....
http://i968.photobucket.com/albums/ae163/Ldiaz12/timingbelt.jpg

JensenB
01-11-2011, 08:57 AM
Yes the belt tension was alot stiffer on one side and uneven when installing, so the sprockets are just a press fit then? I think you may be onto something..I will check my timing and post it tonight i hope. Btw I am using a contitec belt, and the old one was all cracked and ratty, original one with 160k kms..

Ldiaz12
01-11-2011, 09:15 AM
The camshafts have grooved ends so the sprockets pop right out, all you'll need is a 2-3 cam gear puller and they'll be right out. You can get that at any auto parts store, and its advised to use the cam locking tool so that your timing isn't off

walky_talky20
01-11-2011, 10:10 AM
But the position of the sprockets isn't relevant to the position of the position of the Cam shafts.

It is if you leave them alone. The cam sprockets will be exactly as the factory put them. Just like a 1.8T and every other manufacturer's V6 engine. They have a key-way on the sprockets and there is absolutely no way to adjust them. The sprockets on the 2.8 are movable for a fine tune adjustment based on belt length variances, which are slight. So slight that other manufacturers don't even worry about it. Subaru has an even longer belt and 4 cam sprockets, and they don't have any adjustment on the sprockets whatsoever. Just because there is a fine-tune adjustment doesn't mean you have to touch it. Whatever small adjustment is made will be voided over time by the belt stretch anyway. And even tension across the pulleys is meaningless as it will change the split second you hit the starter and load is applied on the belt.

I understand the official procedure using the locking tools. Just, in my opinion, it is completely unnecessary. As long as the new belt goes on as the old one came off (same number of belt teeth between the sprockets), and the belt is within OEM specification, the timing will be accurate. This method will only work if the existing belt timing is correct, though. If the belt timing has jumped, or someone has previously replaced a cam seal without the locking tools, the use of the locking tools is paramount.

^^IMHO. Ldiaz is absolutely correct that, officially, the locking tools should always be used.

Ldiaz12
01-11-2011, 10:18 AM
I respect your opinion and your way of doing things, Im just advising him go on with the procedure without taking shortcuts especially if its his first time doing it.

JensenB
01-11-2011, 02:10 PM
So if my timing is slightly off I will need to pickup the cam locking tool? Or can I just skip it back one tooth?

JensenB
01-11-2011, 07:46 PM
*SOLVED- Thank God! It turns out my timing is still dead on, I just poured some seafoam in the crank and fired it up and the noise slowly and completely vanished! Even if the motor has 10w oil in it in -25C weather, and sitting for a year shouldn't the lifters have primed after 5min of running?? I am going to check the oil pressure next. What is the norm for oil psi? All I do is take out the sender near the oil filter and hookup a mechanical gauge correct? And of course when it reaches operating temps.. THANK YOU for great knowledgeable answers! This has been the best forum for getting answers from actual techs.

walky_talky20
01-11-2011, 07:57 PM
It probably would have quieted down after it warmed up once. But seafoam and an oil change isn't a bad idea after it sat for so long. The 10W oil is probably a bit too heavy for such low temps. I'd recommend you switch to a 5W-30, at least for the winter.

Oil pressure specs from the Bentley, for the 12V 2.8, oil temp at least 176F (80C):

- At idle: 15-36 psi
- At 3,000 RPM: 44-73 psi

JensenB
01-11-2011, 08:40 PM
It probably would have quieted down after it warmed up once. But seafoam and an oil change isn't a bad idea after it sat for so long. The 10W oil is probably a bit too heavy for such low temps. I'd recommend you switch to a 5W-30, at least for the winter.

Oil pressure specs from the Bentley, for the 12V 2.8, oil temp at least 176F (80C):

- At idle: 15-36 psi
- At 3,000 RPM: 44-73 psi

Great, thanks again. I see in your mods list you have got the electronic oil psi gauge, do you remember the thread type/size the sender is?

Ldiaz12
01-11-2011, 08:58 PM
Yea he's right 10w might be to thick, Im running 5 40 fully synthetic. it starts right up in the coldno problems no noise.

walky_talky20
01-11-2011, 10:32 PM
I've got a 1.8T, but is probably the same. Metric 10x1.0 straight threads.

JensenB
01-12-2011, 02:03 PM
Yea he's right 10w might be to thick, Im running 5 40 fully synthetic. it starts right up in the coldno problems no noise.
Im only assuming it has 10w30 in it, Im just seafoaming it before i change it out for 5w30 synthetic.. I only use 5w30-40 up in this climate..

JensenB
01-12-2011, 07:14 PM
I went hunting for metric brass fittings tonight and nobody seems to carry any metric? I wonder if there is a way to just read using Vag com or a multimeter off the oem 1 wire sending unit? Or is it just a simple 2 position deal?

walky_talky20
01-12-2011, 08:01 PM
On the A4 12V 2.8, the OEM piece is not a sender. It is just a switch that closes at 1.8 bar, or about 26 psi. The cluster and/r ecu do not know the actual pressure attained.

You are correct, *nobody* stocks metric fittings. I get them on ebay when I need them. It is kind of joke because half the cars on the road are foreign (and half the domestic cars are foreign design or build). Anyway, to check the oil pressure a mechanic would use a mechanical oil pressure gauge kit. It would likely include all kinds of fitting adapters for every type of thread. The "default" threads on the unit would probably be 1/8" National Pipe Thread (NPT). So he would pull out the 1/8 NPT to M10x1.0 adapter and go to town.

As an interesting detail, the C4 A6/100 also used the 12V V6 engine and they had an oil pressure gauge on the dash from the factory. It even measured in Bar, which is cool. Anyway, the sender for that gauge is specifically referred to in the B5 Bentley manual as "not on the A4", as it *is* shown in the picture(B), right beside the pressure switch(A):

http://i19.photobucket.com/albums/b154/walky_talky20/12V-oil-senders.jpg

JensenB
01-13-2011, 08:55 AM
On the A4 12V 2.8, the OEM piece is not a sender. It is just a switch that closes at 1.8 bar, or about 26 psi. The cluster and/r ecu do not know the actual pressure attained.

You are correct, *nobody* stocks metric fittings. I get them on ebay when I need them. It is kind of joke because half the cars on the road are foreign (and half the domestic cars are foreign design or build). Anyway, to check the oil pressure a mechanic would use a mechanical oil pressure gauge kit. It would likely include all kinds of fitting adapters for every type of thread. The "default" threads on the unit would probably be 1/8" National Pipe Thread (NPT). So he would pull out the 1/8 NPT to M10x1.0 adapter and go to town.

As an interesting detail, the C4 A6/100 also used the 12V V6 engine and they had an oil pressure gauge on the dash from the factory. It even measured in Bar, which is cool. Anyway, the sender for that gauge is specifically referred to in the B5 Bentley manual as "not on the A4", as it *is* shown in the picture(B), right beside the pressure switch(A):

http://i19.photobucket.com/albums/b154/walky_talky20/12V-oil-senders.jpg

I see, I actually went looking for a mechanical oil pressure tester last night too and they seem to be rare as well! I too was checkeing out the fsm on this and apparently it calls for an audi specialty tool once again.. But like you were saying i think all i really need is a metric converting fitting, then hookup an oil pressure gauge...