3B and leaking camshaft seal.

[UrS4boy]

IF you loosen the exhaust cam cap nuts, then you have to retighten them in the sequence noted in this diagram (1, 3 and 5 diagonally in stages to 15 Nm and then 2 and 4 to 15 Nm.)

[maddis]

Yes, of course I have to loosen/tighten them in correct order.

About that diagonal thing. Just checking.

Looking at the picture. Lets say I tighten the cam cap 1 top bolt first, then I should tighten cam cap 3 bottom bolt and then 5 top bolt? I guess that what it means, but just making sure that I understood correctly.

[UrS4boy]

Yes, of course I have to loosen/tighten them in correct order.

About that diagonal thing. Just checking.

Looking at the picture. Lets say I tighten the cam cap 1 top bolt first, then I should tighten cam cap 3 bottom bolt and then 5 top bolt? I guess that what it means, but just making sure that I understood correctly.

Right. Then 1 bottom, 3 top, 5 bottom, etc. Start with 10 Nm, then 12 Nm and finally 15 Nm working up in Stages (although this is mostly for when you are installing a new cam and the cams are totally off). The intent is to not stress and bend/break the camshaft.

[maddis]

Okay. Sounds good. I just have to get new torque wrench. My current ones scale starts at 40Nm.

Lets just hope that, that's enough. Next thing would be replacing the camshaft unless I try those sleeve things. Of course if I replace camshafts it would be easy to change it to something more radical keep in mind the future tune-ups.

Oh well, let's hope that it's not necessary to replace camshafts just yet.

[UrS4boy]

How do you say in Finnish "Can of worms"?

[maddis]

Direct translation would be "Purkki matoja". I'm sure there is better translation, but I cannot think of it now.

[yodasfro]

I just have to say I love the color(oceanic blue) we never got that color on the 200 over here in the states. You might want try the newer style seal made from PTFE(Teflon) when installing it do not oil the surfaces. 038103085C victor reinz comes with a special plastic install sleeve.

[maddis]

I like the color too. I'm just afraid that it's hard to get to look good since I have few spots that I need to repaint after rust repairs. Overall there is very little rust considering that the body is from -85. Doors and front panels are from -90.

Thanks for the tip about that new seal! I think I'll skip using the old type seal anymore and put the engine back together with that new type of seal. I also remembered that I have access to dial meter and I was planning on to measure if the cam shaft really has wobble at the end. I really hope that there aren't any!

Then I'll connect my new valve cover breather to original breather just in case. And after that I really really hope that the seal doesn't leak anymore.

[maddis]

Today I loosen and re-tighten the cam-caps. I just noticed that I made a little mistake and in final torque used 16Nm instead 15Nm. Hopefully that's not too dramatic difference.

Here is picture of the camshaft end.



You can clearly see the groove there probably created by axle seals. The thing is that the groove isn't under the seal's lip if it's pushed all the way in as there is recess(?) in head for the seal to fit. If the seal is pushed all the way in that recess it doesn't yet cover the oil hole at the bottom.

There is also faint brownish mark in the camshaft where the seal meets the camshaft if the seal is pushed all the way in. So I think I'm placing the new seal in between those grooves once it arrives.

Other than that the camshaft looks ok to me.

Here is picture of my failed attempt to measure camshafts free movement. Dial indicator had bit too short tip.

[Thuppu]

You also need to seal the end-cap(that holds the cam seal) surface with some gasket glue. But that you propably knew..?

[UrS4boy]

Here is picture of my failed attempt to measure camshafts free movement. Dial indicator had bit too short tip.

Please don't tell me you rotated the cams while the timing belt was disconnected and the transmission was in gear (i.e. the engine couldn't rotate). The 3B (and the AAN, ABY and ADU) is an interference engine and valves will kiss pistons if the cams are disconnected from the crank.

[maddis]

Well, the text said _failed_ attempt. So no, I didn't rotate the camshafts because the dial meter came too close to nut. And yes, I was aware that the valves can hit the pistons, but I figured that there must be a position for the crankshaft where the camshaft can rotate freely, but turned out that I didn't need to find it.

I need to seal the first cam cap that holds the seal? Because there was no sealant between it and the head when I took it off. Could that been the cause of this whole thing? I checked from Bentley Audi 100, 200 official factory repair manual and there are no mention about sealant in that place. And there is also open hole to the place where oil is flowing freely if not even bit under pressure from chain between camshafts. But I think it wouldn't hurt to put sealant there.

[UrS4boy]

Well, the text said _failed_ attempt. So no, I didn't rotate the camshafts because the dial meter came too close to nut. And yes, I was aware that the valves can hit the pistons, but I figured that there must be a position for the crankshaft where the camshaft can rotate freely, but turned out that I didn't need to find it. I need to seal the first cam cap that holds the seal? Because there was no sealant between it and the head when I took it off. Could that been the cause of this whole thing?

I think you can rotate the exhaust cam indepently of the intake cam (chain removed) and NOT cause any valve-piston contact but I wouldn't risk it.

As for the sealant, I don't think it is normally necessary. In your case, with the worn section of the cam journal, it might help. How you do that without clogging that oil drain hole, I don't know. Sounds dangerous to me. I think you would be better off finding and installing an better (not worn) 3B exhaust cam.

[Thuppu]

Yes, propably.

[maddis]

I don't think the groove in the cam journal is issue. I just have to install the new seal so that it's deeper in the head than what the groove is so the lip doesn't go to that groove.

I'll have to think about the sealant thing. I could of course put very little of it and on the edge of the cam cap and not the whole area so minimizing it to leaking to oil hole, but don't know yet.