Engine noise
03-17-2011, 04:01 PM
#21
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Here's how that is possible. When installing the timing belt, there is a sequence to installing it. You put it on the cam sprockets, then the idler pulley, then the crank sprocket, and the tensioner last. Then you adjust the tension and then tighten the cam sprockets. If not this way, you get slop on the drivers side and the tensioner cannot adjust that out. Look at a picture of the belt routing and you will realize that when everything is tight, the "distance" or number of belt teeth running between the cam sprockets and under the water pump pulley cannot change. Looked kind of sloppy on the drivers side to me too.
I did a compression test, and noticed that all off the sudden the (exposed) drive of the belt was nice and tight. Only to find out that depending on the position the engine is stopped, the one or the other side may get more or less tension (simply by the tension the engine/valve train is putting on it while not running). 6 revolutions later (for the next compression test), and the drive side was sloppy again.
I haven't seen/heard anybody pointing at 'internal' (spun main bearing, connecting rods, etc.) as the source of the noise.
Today, with a nice and warm engine, the noise was (almost) entirely gone (not typical with a worn out bearing or rod, I would say?).
I am at the point to decide the engine is worth putting some more sweat and money into it. So I will order the Blaupart timing belt kit.
Tomorrow, will drain the oil, put fresh in and add 1 quart of Rislone, to be repeated in 2k miles.
By the way:
Compression readings where
Passenger side bank front to rear:
160
125
110
Driver side bank front to rear:
150
125
110
Not good (I assume; and one possible explanation for inadequate power). Not sure what is more likely, pistons or valves?
Maybe a good de-sludge will help (clean the valves and improve compression?). Coincidence that pressure is dropping front to back and both banks similar?
03-18-2011, 02:01 PM
#22
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I have the same problem with my car. Audi A8 2.8 (ACK engine). And already three weeks cannot find solution.
But I think I found good web page with Frequently Asked Questions: http://www.12v.org with those answers:
Tomorrow we will start work on it
I have a lot of valve noise, especially when I first start the engine. It goes away after long drives but tends to stay during stop and go driving. Should I worry?
Given reasonable oil change intervals with the proper weight oil and oil filters, your V6 should be smooth and quiet and not make any ticking noises. A common and easy to check problem is the oil level. While you should be careful not to overfill the oil, you should never let the oil go below the minimum mark on the dipstick.
Assuming that your oil level is OK, you probably need to replace the oil check valves under the valley pan. These valves keep oil at the top of the engine after it shuts down, so that when the engine is started there is adequate lubrication at the top end.
The part numbers for these valves should be no earlier than 078 103 175D.
I have loud valve noise, all the time. What's the problem?
Check your oil level!
If your oil level is OK, you probably have one or two broken oil pressure valves. There is one oil pressure valve in each head that can be accessed by removing the valve cover. These valves keep oil going to the hydraulic lifters at a constant pressure. In the event of a failure of one of these valves, all of the lifters on that side of the engine may have low or no oil pressure. This is a Bad Thing which should be taken care of quickly. If one of these valves has suffered a catastrophic failure, you should probably pick up new hydraulic lifters when replacing the valves -- the lifters are cheap and you will probably have six bad ones.
I have loud valve noise after the car has been idling for a few minutes. What can I do about it?
Check your oil level!
If your oil level is OK, you probably have failing oil pressure valves. There is one oil pressure valve in each head that can be accessed by removing the valve cover. These valves keep oil going to the hydraulic lifters at a constant pressure. In the event of a failure of one of these valves, all of the lifters on that side of the engine may have low or no oil pressure. This is a Bad Thing which should be taken care of quickly.
078 103 363 P pressure limiting valve
But I think I found good web page with Frequently Asked Questions: http://www.12v.org with those answers:
Tomorrow we will start work on it
I have a lot of valve noise, especially when I first start the engine. It goes away after long drives but tends to stay during stop and go driving. Should I worry?
Given reasonable oil change intervals with the proper weight oil and oil filters, your V6 should be smooth and quiet and not make any ticking noises. A common and easy to check problem is the oil level. While you should be careful not to overfill the oil, you should never let the oil go below the minimum mark on the dipstick.
Assuming that your oil level is OK, you probably need to replace the oil check valves under the valley pan. These valves keep oil at the top of the engine after it shuts down, so that when the engine is started there is adequate lubrication at the top end.
The part numbers for these valves should be no earlier than 078 103 175D.
I have loud valve noise, all the time. What's the problem?
Check your oil level!
If your oil level is OK, you probably have one or two broken oil pressure valves. There is one oil pressure valve in each head that can be accessed by removing the valve cover. These valves keep oil going to the hydraulic lifters at a constant pressure. In the event of a failure of one of these valves, all of the lifters on that side of the engine may have low or no oil pressure. This is a Bad Thing which should be taken care of quickly. If one of these valves has suffered a catastrophic failure, you should probably pick up new hydraulic lifters when replacing the valves -- the lifters are cheap and you will probably have six bad ones.
I have loud valve noise after the car has been idling for a few minutes. What can I do about it?
Check your oil level!
If your oil level is OK, you probably have failing oil pressure valves. There is one oil pressure valve in each head that can be accessed by removing the valve cover. These valves keep oil going to the hydraulic lifters at a constant pressure. In the event of a failure of one of these valves, all of the lifters on that side of the engine may have low or no oil pressure. This is a Bad Thing which should be taken care of quickly.
078 103 363 P pressure limiting valve
03-18-2011, 02:16 PM
#23
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I have the same problem with my car. Audi A8 2.8 (ACK engine). And already three weeks cannot find solution.
But I think I found good web page with Frequently Asked Questions: http://www.12v.org with those answers:
Tomorrow we will start work on it I think we will open valley pan, change oil check valves, pressure limiting valve and second time all (6) driver side tappets.
I have a lot of valve noise, especially when I first start the engine. It goes away after long drives but tends to stay during stop and go driving. Should I worry?
Given reasonable oil change intervals with the proper weight oil and oil filters, your V6 should be smooth and quiet and not make any ticking noises. A common and easy to check problem is the oil level. While you should be careful not to overfill the oil, you should never let the oil go below the minimum mark on the dipstick.
Assuming that your oil level is OK, you probably need to replace the oil check valves under the valley pan. These valves keep oil at the top of the engine after it shuts down, so that when the engine is started there is adequate lubrication at the top end.
The part numbers for these valves should be no earlier than 078 103 175D.
I have loud valve noise, all the time. What's the problem?
Check your oil level!
If your oil level is OK, you probably have one or two broken oil pressure valves. There is one oil pressure valve in each head that can be accessed by removing the valve cover. These valves keep oil going to the hydraulic lifters at a constant pressure. In the event of a failure of one of these valves, all of the lifters on that side of the engine may have low or no oil pressure. This is a Bad Thing which should be taken care of quickly. If one of these valves has suffered a catastrophic failure, you should probably pick up new hydraulic lifters when replacing the valves -- the lifters are cheap and you will probably have six bad ones.
I have loud valve noise after the car has been idling for a few minutes. What can I do about it?
Check your oil level!
If your oil level is OK, you probably have failing oil pressure valves. There is one oil pressure valve in each head that can be accessed by removing the valve cover. These valves keep oil going to the hydraulic lifters at a constant pressure. In the event of a failure of one of these valves, all of the lifters on that side of the engine may have low or no oil pressure. This is a Bad Thing which should be taken care of quickly.
078 103 363 P pressure limiting valve
But I think I found good web page with Frequently Asked Questions: http://www.12v.org with those answers:
Tomorrow we will start work on it
I think we will open valley pan, change oil check valves, pressure limiting valve and second time all (6) driver side tappets.I have a lot of valve noise, especially when I first start the engine. It goes away after long drives but tends to stay during stop and go driving. Should I worry?
Given reasonable oil change intervals with the proper weight oil and oil filters, your V6 should be smooth and quiet and not make any ticking noises. A common and easy to check problem is the oil level. While you should be careful not to overfill the oil, you should never let the oil go below the minimum mark on the dipstick.
Assuming that your oil level is OK, you probably need to replace the oil check valves under the valley pan. These valves keep oil at the top of the engine after it shuts down, so that when the engine is started there is adequate lubrication at the top end.
The part numbers for these valves should be no earlier than 078 103 175D.
I have loud valve noise, all the time. What's the problem?
Check your oil level!
If your oil level is OK, you probably have one or two broken oil pressure valves. There is one oil pressure valve in each head that can be accessed by removing the valve cover. These valves keep oil going to the hydraulic lifters at a constant pressure. In the event of a failure of one of these valves, all of the lifters on that side of the engine may have low or no oil pressure. This is a Bad Thing which should be taken care of quickly. If one of these valves has suffered a catastrophic failure, you should probably pick up new hydraulic lifters when replacing the valves -- the lifters are cheap and you will probably have six bad ones.
I have loud valve noise after the car has been idling for a few minutes. What can I do about it?
Check your oil level!
If your oil level is OK, you probably have failing oil pressure valves. There is one oil pressure valve in each head that can be accessed by removing the valve cover. These valves keep oil going to the hydraulic lifters at a constant pressure. In the event of a failure of one of these valves, all of the lifters on that side of the engine may have low or no oil pressure. This is a Bad Thing which should be taken care of quickly.
078 103 363 P pressure limiting valve
03-19-2011, 02:22 AM
#25
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Sorry not ACK...my engine is AFC version (http://www.12v.org/engine/index.php?section=fe) 1995 Audi A8 2.8 with 12valves (http://www.12v.org/engine/index.php?section=id). Tappets = Hydraulic Valve lifter, part code (ETKA program) 050 109 309 J.
03-19-2011, 09:52 AM
#27
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Crazy, I know you are a lot younger than I am, but in engineering speak the tappet is the hydraulic valve lifter, although tappet has fallen out of favor as a term. In the stone age, i.e. back in the lifter pushrod rocker arm days, the slight noise of those three components could be easily adjusted out by adjusters on rocket arms that were shaft mounted, or putting another turn on the nut holding independant rocker arms. As I read Bentleys, you have to replace the lifter and there is no provision for shims to tighten this up. Although there was a measurement for determining lifter replacement, I did not see any measurement for the cam lobe itself. Strange. Maybe grumbu is ancient like me.
03-19-2011, 01:26 PM
#28
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I'm fro Europe, not very old, and my work is not related with car repairing, but I like find out everything about failures - especially when applied my car Sometimes human terms do not coincide with the official catalog terms (in this case - ETKA)
Sometimes human terms do not coincide with the official catalog terms (in this case - ETKA)
03-19-2011, 11:24 PM
#29
AudiWorld Super User
hubturn: haha, i might be younger, but im very familiar with mechanical lifters :-) ive build quite a few vw type 1 motors starting from basic single port 1500cc engines to stroker motors (currently working on a 2110cc) :-) I'm also a big Dnepr head (MT10-36 and MT11-32) owned both of those bikes, i was around them since i can remember, they were the first motors i was learning to work on with my grandfather.
I've just never heard the term "tappet". I've used to work for a VW dealer for a few years as a parts consultant, and I'm very familiar with the ETCA catalog, and they are called "hydraulic lifters" and yes, they do fail and they do have to be replaced once in a while, but before you go thrum all the hassle of replacement. Run some cleaners thrum the engine block, do couple synthetic oil changes. how many miles on the engine? what type of oil do you use?
p.s. i wish i head a Dnepr here in the states :-(
I've just never heard the term "tappet". I've used to work for a VW dealer for a few years as a parts consultant, and I'm very familiar with the ETCA catalog, and they are called "hydraulic lifters" and yes, they do fail and they do have to be replaced once in a while, but before you go thrum all the hassle of replacement. Run some cleaners thrum the engine block, do couple synthetic oil changes. how many miles on the engine? what type of oil do you use?
p.s. i wish i head a Dnepr here in the states :-(
03-20-2011, 08:59 AM
#30
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My understanding is that the word "tappet" isn't used any more because the tappet was used as a HAND adjustable means to control the opening travel range of valves, both intake and exhaust. You would hear "tappet lash" on an air-cooled bike very clearly as something akin to a sewing machine needing some oil. The bikes most renowned for this noise were the old "air-head" boxer twin R-series BMW's, which are the design inspiration for the Ural (I think) in Crazy's photo.
Nowadays, nobody does valve lash adjustments anymore, because the system is self-adjusting hydraulically. If you hear this kind of "tappet" noise, it is likely due to carbon build up that is not allowing the system to adjust. STFA for "Seafoam the engine." Do this first, then drive gently for a few hundred miles, then do it again. After the second soak, the adjusters should be able to move freely enough to catch up to the rest of your valves' proper settings.
Cheers,
LG
Nowadays, nobody does valve lash adjustments anymore, because the system is self-adjusting hydraulically. If you hear this kind of "tappet" noise, it is likely due to carbon build up that is not allowing the system to adjust. STFA for "Seafoam the engine." Do this first, then drive gently for a few hundred miles, then do it again. After the second soak, the adjusters should be able to move freely enough to catch up to the rest of your valves' proper settings.
Cheers,
LG
Last edited by Loudgoldwing; 03-20-2011 at 09:06 AM.