M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine + Driveline => Topic started by: Jtuner on August 16, 2006, 12:59:22 PM
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I'm gonna go ahead and replace my timing chain tensioner piston.. I've been looking at the blow up of it, and it looks to me like you just loosen the 17(19??)mm bolt that sits on the side of the assy., right above the air conditioning compressor, pull it out and replace?? Is it really this simple to do??? Any help would be appreciated!
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Yep... it's really that simple.
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Then just rev the engine to around 3500rpm....This "expands" the unit...
10 minute job.....
1 minute to take out...
1 minute to put new one in.....
8 minutes to drink a beer in between....LMAO
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Ok damn.. so I take it out, drink 3 beers, put new one in, drink 1 more beer, start the car and rev it to 3500rpm for,, a few seconds? then finish my 6 pack?
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Before you replace or rev check this site. There are numerous threads on this. I have a new tensioner but am holding off for now. Inpart because I "think" it "might" put new tension on an old chain. As far as the rev, I think I read that was a huge no-no.
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The biggest reason the belts fail is because the tensioner goes bad and lets the timing chain flap around or lets it skip a tooth, causing damage. I've never heard of the chain breaking from extra tension from the tensioner. The tensioner is actually driven off of oil pressure (I think), and eventually gets gopped up and goes limp! Yes, we're still talking about the timing chain tensioner. ;)
If your engine runs good now, you should be fine to just replace the tensioner. And, yes, it really is that easy! :D
Replace the tensioner ring seal when you do it too would be my only other advice. It's a <$2 part at the dealer.
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I think it was BMW91 and Sheepdog who had some thoughts on it. I will look for the thread and link. H#$$ I am beginning to wonder if this M42 engine is time bomb.
here you go
http://www.m42club.com/forums/showthread.php?t=840
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H#$$ I am beginning to wonder if this M42 engine is time bomb.
here you go
http://www.m42club.com/forums/showthread.php?t=840 (http://www.m42club.com/forums/showthread.php?t=840)
They all are!
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Here is a write on repalcement:
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00072&Section=08
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well, hard to argue with D. Clay...
seriously, I wouldn't worry about it... first things first... find your oil leak.
If yer timing chain is making a racket, put the new tensioner in, rev the engine at 3500 till the chain quiets down. If installing the tensioner causes your chain or sprocket to wig out, trust me, you have bigger problems. It happens. Put the new tensioner in and see how it goes --you will be fine.
While we're here... want something else to keep yourself up at night? In the head, there's this aluminium bung (sheepdog might have a pic of it) that's just, well... pressed in there!
I can't believe they don't fail like, all the time. go figure
--then again, I live in NYC and I'm amazed that more people aren't killed by air conditioning units falling out of window sills.
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Awesome write up :) thanks everyone!!
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Do not do the 3500 rpm thing.
If your timing chain is new(ish) ist woudl probably be ok, but if you are over 100k, I would not do that.
After what I have seen it could be the original engineer telling you to do that and have the Pope giving his blessing, I would not do that again.
You have no idea how good your oil pressure is, or how good your timing chain is. If your pump is pushing 100% pressure it can take longer for the piston to pop out, meaning your chain is beating your timing case to death for even longer.
Basically I do not care who the hell says this is ok to do, think for a moment what is happenning during the time your chain is not tensioned properly. The chain is slapping around, cams are going in and out of proper timing, the chain is slapping aluminum peices thata re woirth $300(!) and smashing rollers into the sprockets possibly breaking rollers.
We already know the oil pump screen is worthless, so if you break a timing chain roller, it is likely to find its way into the pump, leading to exactly what I had happen.
No offence to D. Clay, but hat write up is shit. I questioned it when I read it, and after seeing what has happenned to my engine and Bmwman91's and others, no way would I do that again.
If it works, and I am sure it has for many people, I question how much damage it did. The problem is that when it does not work, it will cost you A LOT of money and time to repair. Timing chains are around $100, housings are $300, gaskets are about $80, Oil Pump is around $150, pickups are $25, and that is just the bare minimum. If you pay someone to do it, add nearly a grand in labor maybe more, maybe less.
My advice, either put the tensioner in, popped. or pull the valve cover and upper cam coverand pop it loose once it is in. This is far safer and only takes a few more minutes to do.
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While we're here... want something else to keep yourself up at night? In the head, there's this aluminium bung (sheepdog might have a pic of it) that's just, well... pressed in there!
Not sure what you are reffering to. If I spot it, I will get a picture.
Keep in mind, older American V8's had pressed in brass plugs in the blocks.
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Keep in mind, older American V8's had pressed in brass plugs in the blocks.
All out motors have freeze plugs, so there you go. Mine haven't moved a scoge.
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Do not do the 3500 rpm thing.
If your timing chain is new(ish) ist woudl probably be ok, but if you are over 100k, I would not do that.
After what I have seen it could be the original engineer telling you to do that and have the Pope giving his blessing, I would not do that again.
You have no idea how good your oil pressure is, or how good your timing chain is. If your pump is pushing 100% pressure it can take longer for the piston to pop out, meaning your chain is beating your timing case to death for even longer.
Basically I do not care who the hell says this is ok to do, think for a moment what is happenning during the time your chain is not tensioned properly. The chain is slapping around, cams are going in and out of proper timing, the chain is slapping aluminum peices thata re woirth $300(!) and smashing rollers into the sprockets possibly breaking rollers.
We already know the oil pump screen is worthless, so if you break a timing chain roller, it is likely to find its way into the pump, leading to exactly what I had happen.
No offence to D. Clay, but hat write up is shit. I questioned it when I read it, and after seeing what has happenned to my engine and Bmwman91's and others, no way would I do that again.
If it works, and I am sure it has for many people, I question how much damage it did. The problem is that when it does not work, it will cost you A LOT of money and time to repair. Timing chains are around $100, housings are $300, gaskets are about $80, Oil Pump is around $150, pickups are $25, and that is just the bare minimum. If you pay someone to do it, add nearly a grand in labor maybe more, maybe less.
My advice, either put the tensioner in, popped. or pull the valve cover and upper cam coverand pop it loose once it is in. This is far safer and only takes a few more minutes to do.
I see what you're sayin for sure,, if you pop the spring out while putting it in, would it be super hard to push in? or if I took off the valve cover, and upper casing for the chain, can I simply use a needle nose to pull out the snap ring?
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I was referring to all engines. However, I now have A/C units falling from the sky to add to the list. Makes me glad I live in a one-story town. I've become hesitant to say my M42 has 198,000 on it and only the timing chain tensioner replaced. I had the valve cover and upper timing cover off and popped it out before I started up the car. The reason I had them off was to check the chain and cam sprockets because I was still trying to find what was making it sound like a diesel. I didn't even know that this was an M42 deal at the time. It's 104 outside and I'm waiting for it to go down to the low 90's again to do a few things to it. I might put a pan gasket on it just to take a peek.
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My advice, either put the tensioner in, popped. or pull the valve cover and upper cam cover and pop it loose once it is in. This is far safer and only takes a few more minutes to do.
I have thought about this more, and agree with sheepdog.
D Clay, you know Dave Hickey? Howsabout Bill Hicks?
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Hey guys, just had a thought today,, Since my chain tension is very intermittant(sometimes its loud, sometimes its perfect), you don't think I may have an oil pressure issue do you? Like possibly the tensioner sometimes gets enough oil and there's no racket, and if its starved the chain flops loose a bit and makes the racket? How can I check it? or more specifically, how can I check my oil pump screen to see if its stopped up? I'm guessing if that was the case, the car wouldn't run very long, and the car runs great... I do have a very miniscule oil leak (i'd say 1/4 quart a month) which doesn't really matter with regular oil changes anywayz etc... Let me know what you think
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D Clay, you know Dave Hickey? Howsabout Bill Hicks?
I know of them but unfortunately have never personally met them. Hicks of course has been dead for 10 years or more. For those who don't know, there are whole neighborhoods in Austin that aren't even in the US much less Texas. On the electoral map it's a blue dot in a red state and with the University and the Capitol, has always attracted "strangers" from small town Texas. The film Slacker, filmed in Austin, is considered a documentary here!
I was talking to Terry Sayther who has a BMW repair shop here in town and I asked him about M42's and timing chains. His experience indicated that it's not a rare problem but also not common either. Prevention is changing the oil regularly, Once the wear occurs to the rails, it tends to get worse. Be wary of the "sewing machine" sound. And he was impressed with the Coil-on-Plug deal that bmwman91 made.
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Hey guys, just had a thought today,, Since my chain tension is very intermittant(sometimes its loud, sometimes its perfect), you don't think I may have an oil pressure issue do you? Like possibly the tensioner sometimes gets enough oil and there's no racket, and if its starved the chain flops loose a bit and makes the racket? How can I check it? or more specifically, how can I check my oil pump screen to see if its stopped up? I'm guessing if that was the case, the car wouldn't run very long, and the car runs great... I do have a very miniscule oil leak (i'd say 1/4 quart a month) which doesn't really matter with regular oil changes anywayz etc... Let me know what you think
I am by no means a mechanic, I don't play one on TV nor did I stay at a Holiday Inn Express last night.
My engine was making an intermittent ticking. My problem turned out to be the oil filter housing gasket. It had been replaced the day before but had folded over and was covering the "pressure inlet" or the pencil size hole near the base.
Have you changed that gasket?
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I personally haven't changed it recently, but I don't know what kind of prior service was done to the car :( It would definatly be something to check in to when I can get it on the lift at school.. That would make a lot of sense.. I think I'll still replace the tensioner to be safe, but I just wanna make sure that I'm definatly not having oil pressure problems.. I want to turbocharge eventually, so I want my engine pristine when the snail goes on :) Thx for all the input on this thread guys!
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I'll be honest here.
Since replacing the tensioner, its been a PITA ever since. At cold start-ups, it rattles like never before and its loud! Once it warms up, it quites down a bit. ....and Yes, it was a new tensioner :confused:
Also, it leaks where it plugs into the block. I mean, I've followed all the DIY's and write ups on how much torque to apply to the tensioner, but I still get a small oil weep. Even added a bit more of torque just in case. :mad:
I should've left it alone :(
Oh well, in my opinion, I've wasted $ on two useless upgrades: the tensioner and the $170 "performance" ignition wires from BAVAUTO :mad:
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I'm hearing a new "rattle" coming from the area near the thermostat. Is that the area you'll hear the timing chain rattle from?
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I'll be honest here.
Since replacing the tensioner, its been a PITA ever since. At cold start-ups, it rattles like never before and its loud! Once it warms up, it quites down a bit. ....and Yes, it was a new tensioner :confused:
Also, it leaks where it plugs into the block. I mean, I've followed all the DIY's and write ups on how much torque to apply to the tensioner, but I still get a small oil weep. Even added a bit more of torque just in case. :mad:
I should've left it alone :(
Oh well, in my opinion, I've wasted $ on two useless upgrades: the tensioner and the $170 "performance" ignition wires from BAVAUTO :mad:
Did you replace the crush washer?
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yes
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Oil Pump is around $150
I think i just ordered one (the "rotor set") from bma for $44