The dreaded M272 Balance Shaft
08-28-2018, 08:52 PM
#551
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Join Date: Feb 2014
Location: MA
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2008 E350 4Matic, 2011 E350 4matic
I bet mine was at a lower mileage than yours. 44700
I bought the car in 09 with 22k, so if there were reports of this issue they were FEW.
I did plenty of research and tried to get estimates from indys but was turned down. At least I got 15% off as I was well over a year from the tiered settlement date.
I get a little pissed I admit it, when someone says I don't know what caused an obvious wear problem due to bad materials.
Still pissed that MB didnt cover the whole repair and made a car thats already had this and a transmission issue, im only at 48000 and had the transmission go to limp mode,
which I had repaired by shipping the control module and had its electrics repaired. Then I the damn indy shop didnt put the trans gasket in correctly and it leaked.
So I bought a transfer pump and another new gasket and did it myself. NO leaks and working great now. Next issue the Fing SBC brake bs!
I bought the car in 09 with 22k, so if there were reports of this issue they were FEW.
I did plenty of research and tried to get estimates from indys but was turned down. At least I got 15% off as I was well over a year from the tiered settlement date.
I get a little pissed I admit it, when someone says I don't know what caused an obvious wear problem due to bad materials.
Still pissed that MB didnt cover the whole repair and made a car thats already had this and a transmission issue, im only at 48000 and had the transmission go to limp mode,
which I had repaired by shipping the control module and had its electrics repaired. Then I the damn indy shop didnt put the trans gasket in correctly and it leaked.
So I bought a transfer pump and another new gasket and did it myself. NO leaks and working great now. Next issue the Fing SBC brake bs!
08-28-2018, 09:30 PM
#552
Hey Shack1, Now that is great news for you on the SBC!
i have a 08 C350, 07 CLS550 and 11 E350 so as much as I want to complain about the sprocket the cars are awesome.
i have a 08 C350, 07 CLS550 and 11 E350 so as much as I want to complain about the sprocket the cars are awesome.
08-28-2018, 10:37 PM
#553
Member
08-29-2018, 01:02 AM
#555
Member
08-30-2018, 12:33 PM
#558
Junior Member
I hope someone finds this helpful.
Even if your M272 engine serial number falls within the range of those with bad balance shafts DOES NOT automatically mean it is bad!!
Here is an easy way to check. Rotate the engine to TDC (tope dead center) which is when the 305 mark on the crank pulley lines up with the arrow or mark on the engine block above the crank pulley. You will need a 19mm socket and long breaker bar. These marks are hard to see if you have an older vehicle with 150K miles like mine so I had to mark it with craft paint for future reference haha.
Once you do the that remove camshaft position sensors (I think it is two or three 10mm bolts). Look inside to see if the markings are all within the circle. If they are, CONGRATS!!!! You don't have a bad balance shaft. See youtube video below!!
Here is an easy way to check. Rotate the engine to TDC (tope dead center) which is when the 305 mark on the crank pulley lines up with the arrow or mark on the engine block above the crank pulley. You will need a 19mm socket and long breaker bar. These marks are hard to see if you have an older vehicle with 150K miles like mine so I had to mark it with craft paint for future reference haha.
Once you do the that remove camshaft position sensors (I think it is two or three 10mm bolts). Look inside to see if the markings are all within the circle. If they are, CONGRATS!!!! You don't have a bad balance shaft. See youtube video below!!
08-30-2018, 01:17 PM
#559
This is helpful but it doesn’t mean that you don’t have a bad balance shaft. This means that you haven’t jumped timing yet.
The scope of the gear is the only way to check. Or pull the timing cover of course but then you would be fixing the problem.
The scope of the gear is the only way to check. Or pull the timing cover of course but then you would be fixing the problem.
08-30-2018, 01:57 PM
#560
Member
I hope someone finds this helpful. https://www.youtube.com/watch?v=XXQArmxXsnM
Even if your M272 engine serial number falls within the range of those with bad balance shafts DOES NOT automatically mean it is bad!!
Even if your M272 engine serial number falls within the range of those with bad balance shafts DOES NOT automatically mean it is bad!!
I have read nearly all the posts, bulletins and websites on the balance shaft and have yet to read of a motor jumping teeth,
its not the balance shaft sprocket that keeps the timing.
08-30-2018, 02:23 PM
#561
Junior Member
Again, I think if the circles are in the center when you take off cam position sensors then the issue is likely the sensors themselves and not the balance shaft.
What do you mean it just means you haven't jumped timing yet? If the balance shaft was bad or damaged, I believe the timing gears on the balance shaft would be worn and timing would've already jumped. I could be wrong but I checked mine with this method, then changed the appropriate camshaft position sensors on the bank that throwing the code (I think it was one on each side but don't remember if it was the sensor exhaust or intake). That cleared the codes and I haven't seen them in 18 months (Knock on wood).
Last edited by Travis Ceccacci; 08-30-2018 at 02:32 PM.
08-30-2018, 03:13 PM
#562
You guys are both right and the cam position sensors needing replacement throws in another variable.
Assuming those are good you can chug along and do nothing until the codes throw. Then in an emergency you need to schedule a repair.
I decided not to wait and did mine at my convenience.
The balance shaft does affect timing though. What happens is the gear wears down and the tensioner exceeds its limit. The cam gears get out of sync and there go the codes. Make sense?
so the video posted is correct that you don’t have the problem now by checking the windows but it doesn’t mean that you won’t get it.
Assuming those are good you can chug along and do nothing until the codes throw. Then in an emergency you need to schedule a repair.
I decided not to wait and did mine at my convenience.
The balance shaft does affect timing though. What happens is the gear wears down and the tensioner exceeds its limit. The cam gears get out of sync and there go the codes. Make sense?
so the video posted is correct that you don’t have the problem now by checking the windows but it doesn’t mean that you won’t get it.
08-30-2018, 03:16 PM
#563
Btw the cam sensors leak and the o rings get old and are known problems. They are relatively easy to replace so no sense in waiting on that. Save money by not needing to do that in an emergency and order at the best price.
08-30-2018, 03:28 PM
#564
Member
You guys are both right and the cam position sensors needing replacement throws in another variable.
Assuming those are good you can chug along and do nothing until the codes throw. Then in an emergency you need to schedule a repair.
I decided not to wait and did mine at my convenience.
The balance shaft does affect timing though. What happens is the gear wears down and the tensioner exceeds its limit. The cam gears get out of sync and there go the codes. Make sense?
so the video posted is correct that you don’t have the problem now by checking the windows but it doesn’t mean that you won’t get it.
Assuming those are good you can chug along and do nothing until the codes throw. Then in an emergency you need to schedule a repair.
I decided not to wait and did mine at my convenience.
The balance shaft does affect timing though. What happens is the gear wears down and the tensioner exceeds its limit. The cam gears get out of sync and there go the codes. Make sense?
so the video posted is correct that you don’t have the problem now by checking the windows but it doesn’t mean that you won’t get it.
08-30-2018, 03:44 PM
#565
Hey Shack is back and reading up on this now. Of course it could jump a tooth. Just think about it. The chain would eventually have too much slack.
This doesn’t typically happen though because the codes throw that the cam(s) position is out of range first and people get it fixed.
With a balance shaft engine the teeth on the balance shaft gear worn down would cause it to jump timing and now you have more problems.
This doesn’t typically happen though because the codes throw that the cam(s) position is out of range first and people get it fixed.
With a balance shaft engine the teeth on the balance shaft gear worn down would cause it to jump timing and now you have more problems.
08-30-2018, 03:46 PM
#566
Member
Reading up on it now. LMAO
Even with the teeth gone, there isnt enough slack. Ill post a pic of mine so you know what we are talking about.
Show me a incident where this has happened?
Last edited by Shack1; 08-30-2018 at 03:50 PM.
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pete diegan (02-01-2022)
08-30-2018, 04:46 PM
#567
Why is this so difficult to comprehend? If this is your gear and the only thing keeping that offset weight to stay in timing with the engine is the teeth then why would it not jump timing?
08-30-2018, 04:49 PM
#569
Member
Whats your deal with HAVING to be right? I love that you showed me a pic of what I just showed you. That's not the timing gear, would it matter if it jumped a tooth on the balance shaft?
Last edited by Shack1; 08-30-2018 at 04:53 PM.
08-30-2018, 06:27 PM
#570
Shack1,
I’m not trying to be a dik. I just don’t want people inspecting the cam windows and walking away that they don’t have the balance shaft problem because it happens to be in alignment that day. The post above sort of implies that.
Regarding timing. There isn’t a specific timing gear here. You seem hung up on that and are trying to disregard the importance of the balance shaft itself and the fact that it is a critical part of timing on these engines.
The balance shaft has to set in relation to the cam gears and crank. The weight has to be rotated to a mark and the chain has a link to line up. Then the crank and cam gears are set. All of this makes up the timing.
If it jumped teeth like it would in the photo the offset weight would spin out of timing and vibrate the engine.
Cool?
I’m not trying to be a dik. I just don’t want people inspecting the cam windows and walking away that they don’t have the balance shaft problem because it happens to be in alignment that day. The post above sort of implies that.
Regarding timing. There isn’t a specific timing gear here. You seem hung up on that and are trying to disregard the importance of the balance shaft itself and the fact that it is a critical part of timing on these engines.
The balance shaft has to set in relation to the cam gears and crank. The weight has to be rotated to a mark and the chain has a link to line up. Then the crank and cam gears are set. All of this makes up the timing.
If it jumped teeth like it would in the photo the offset weight would spin out of timing and vibrate the engine.
Cool?
08-30-2018, 06:36 PM
#571
Member
Shack1,
I’m not trying to be a dik. I just don’t want people inspecting the cam windows and walking away that they don’t have the balance shaft problem because it happens to be in alignment that day. The post above sort of implies that.
Regarding timing. There isn’t a specific timing gear here. You seem hung up on that and are trying to disregard the importance of the balance shaft itself and the fact that it is a critical part of timing on these engines.
The balance shaft has to set in relation to the cam gears and crank. The weight has to be rotated to a mark and the chain has a link to line up. Then the crank and cam gears are set. All of this makes up the timing.
If it jumped teeth like it would in the photo the offset weight would spin out of timing and vibrate the engine.
Cool?
I’m not trying to be a dik. I just don’t want people inspecting the cam windows and walking away that they don’t have the balance shaft problem because it happens to be in alignment that day. The post above sort of implies that.
Regarding timing. There isn’t a specific timing gear here. You seem hung up on that and are trying to disregard the importance of the balance shaft itself and the fact that it is a critical part of timing on these engines.
The balance shaft has to set in relation to the cam gears and crank. The weight has to be rotated to a mark and the chain has a link to line up. Then the crank and cam gears are set. All of this makes up the timing.
If it jumped teeth like it would in the photo the offset weight would spin out of timing and vibrate the engine.
Cool?
08-30-2018, 07:26 PM
#572
Out Of Control!!
Probably why they thought it did not have to be as hardened since there is minimal load.
08-30-2018, 07:28 PM
#573
Out Of Control!!
Shack1,
I’m not trying to be a dik. I just don’t want people inspecting the cam windows and walking away that they don’t have the balance shaft problem because it happens to be in alignment that day. The post above sort of implies that.
Regarding timing. There isn’t a specific timing gear here. You seem hung up on that and are trying to disregard the importance of the balance shaft itself and the fact that it is a critical part of timing on these engines.
The balance shaft has to set in relation to the cam gears and crank. The weight has to be rotated to a mark and the chain has a link to line up. Then the crank and cam gears are set. All of this makes up the timing.
If it jumped teeth like it would in the photo the offset weight would spin out of timing and vibrate the engine.
Cool?
I’m not trying to be a dik. I just don’t want people inspecting the cam windows and walking away that they don’t have the balance shaft problem because it happens to be in alignment that day. The post above sort of implies that.
Regarding timing. There isn’t a specific timing gear here. You seem hung up on that and are trying to disregard the importance of the balance shaft itself and the fact that it is a critical part of timing on these engines.
The balance shaft has to set in relation to the cam gears and crank. The weight has to be rotated to a mark and the chain has a link to line up. Then the crank and cam gears are set. All of this makes up the timing.
If it jumped teeth like it would in the photo the offset weight would spin out of timing and vibrate the engine.
Cool?
The following users liked this post:
Shack1 (08-30-2018)
08-30-2018, 07:28 PM
#574
Out Of Control!!
08-30-2018, 09:26 PM
#575
If the balance shaft sprocket is the soft material and wears out enough to let the chain skip it, that does not mean the other sprockets will lose timing, only if they get jumped as well from a very loose chain or wear just like the balance sprocket. Now that video could show a worn chain condition.
The following users liked this post:
Shack1 (08-30-2018)
