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Tensioner replacment issue

  #1  
Old 07-19-2016, 10:22 PM
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Default Tensioner replacment issue

Alright. Here's the deal. The tensioner on the passenger side has been rattling at start-up every so often for a while. I bought a valve cover seal, cam/tensione seals, and tensioner pad set from Blauparts with the intention of replacing the pads. Well, the passenger side started making a racket a couple of weeks ago. It was running ok and drove it the last 3 miles to the house. I pulled the valve cover and there was a piece of the lower tensioner pad laying there. Went ahead and ordered tensioners for both sides and began disassembly. Also went ahead and got a new timing belt.

Over the past week, I've gotten the tensioners and cams back in and everything, carefully lining everything up. This evening I go out to put the timing belt on and get everything tensioned correctly on the first try. I was smelling success... Removed the cam bar and crank lock. Slowly rotated the engine over by hand two revolutions. While turning the engine over, the chain tensioners were popping up and down. Is this normal? Anyway, I get back to just past TDC a degree or so (about the width of the Sharpie mark I'd made for reference before turning everything.). The timing marks on the cams lined up. Since I had gone just a smidge past TDC, the cam lock bar wouldn't go on without turning it just a hair backward. I didn't want to do that because it messes with the timing belt tension, I proceeded to go ahead with 2 more manual rotations being sure to try and stop just before TDC and tap it the rest of way to the point to where the cam lock bar would go in as it reached TDC.

The chain tensioners were still popping up and down like they did on the first two revolutions. I get about 3/4 of the way through the second revolution and it stops as if there is interference this time. Sonofaf------kin....... WHAT THE HELL?

Am I going to have to take this GD thing all the way back apart again. WTF is it with the tensioners popping like that? Any pointers.. Suggestions? This damned thing is really trying my patience.
 

Last edited by dave944; 08-12-2016 at 08:00 AM.
  #2  
Old 07-20-2016, 12:27 AM
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Well. I just went out and pulled the cam shafts and tensioners back out. The crank is hitting something in the block somewhere probably a frikkin chunk of the damned tensioner pad. No valves are bent so that's not the issue.
 
  #3  
Old 07-20-2016, 12:39 AM
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Now I have another question. If I remove the lower oil pan, which I think can be removed without too much trouble (pulling the engine), can I see enough of the bottom of the block to determine if there is any tensioner pad debris in there that could be causing the obstruction?
 

Last edited by dave944; 07-20-2016 at 08:29 AM.
  #4  
Old 07-23-2016, 06:25 PM
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Turned out to just be a couple of chunks of carbon falling into the cylinders when beating on the damed cam bearing cover bolts. Once I removed the cams again, I filled the cylinders with Sea Foam (an engine cleaner here in the US) and mineral spirits to the tops of the spark plug tubes. They did not leak down thus verifying that there were no bent valves. I pumped the fluid back out of the cylinders after a couple of hours. Turned the engine over by hand rocking it back and forth as it started to bind. After a few cycles it would start to go on past the binding point. Then I'd rock it back and forth over the binding point and it cleared up. There was a tiny bit of fluid still left in each cylinder thanks to the long spark plug tubes. I guess the rocking and agitating of the fluid and carbon bits, they broke up. Now she spins over freely again... Shewww. That was a relief. I've refilled the cylinders with straight Sea Foam to let it dissolve more of the carbon on the pistons though. Looking at them with the bore scope, they looked like the face of a coal mine... I hope to reassemble everything tomorrow and get this tank back on the road again.
 

Last edited by dave944; 08-12-2016 at 08:03 AM.
  #5  
Old 07-28-2016, 08:51 AM
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The beast has been tamed.... After fighting me almost every step of the way, I got it back together and running last night. Smoked like a freight train at first because of the oil I had put down in the cylinders to lube them back up from being flooded with mineral spirits and oil. I spun it over several times with the spark plugs out so it wouldn't hydraulic on me. She's nice and quiet now. Runs like a top. I ended up electing to go with 15nm on the cam bearing and tensioner bolts. The Bentley manual lists 15nm in one section (overall component list) and 5mn + 1/4 turn in the actual assembly section. I wish they would get there crap straight. The new bolts are 9.8's and the 5mn + 1/4turn stripped the threads on the 3rd bolt I torqued so they are NOT TTY. Had to heli-coil it. The engine has 215K miles on it so if it lasts till the
next timing belt change (new belt on it now), I'll be happy and I'll be sure to keep an eye (or more like an ear) out for any sign of noise coming from the cams and will be pulling the covers off to check them should I hear any indication of trouble.
 

Last edited by dave944; 08-12-2016 at 08:04 AM.
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