How often do you change your chain tensioner?

[eur04lif3]

Previous owner was very good at maintaining the car, and i have two receipts from him that he purchased a new tensioner.
Here's how the sprockets looked when i bought the car:





I've owned the car for little over a year now, and changed it once already.

Just curious to know how often do you guys change your tensioner?

PS. my motor has 213k on it.

[TobyB]

at 170k, 2 of the 3 sliders on my M42 were delaminating- I took them off, tugged a little
bit, and the plastic came right off the metal.

I didn't feel too bad about changing them at that point.

Adjuster? Every 100k.

[roguetoaster]

Changed mine when I got the car, then again 2+ years and ~21k miles later when I thought I heard a bit of noise.

[eur04lif3]

at 170k, 2 of the 3 sliders on my M42 were delaminating- I took them off, tugged a little
bit, and the plastic came right off the metal.

I didn't feel too bad about changing them at that point.

Adjuster? Every 100k.

Interesting...

Changed mine when I got the car, then again 2+ years and ~21k miles later when I thought I heard a bit of noise.

Do you have video of the said noise?
That's the reason i changed mine as well, i though i was hearing some excessive noise.

[roguetoaster]

Do you have video of the said noise?
That's the reason i changed mine as well, i though i was hearing some excessive noise.

No video, but a tensioner going bad sounds like a very fast lifter tick distinctly from the front of the engine. Of course, by the time you hear it from the cabin you have probably already damaged timing components. I changed it because I had another part on hand and I was being slightly paranoid, er... maintenance conscious.

[TobyB]

Oh, and for the record, mine was apart because I heard "some" noise,
so whether the adjuster hastened the demise of the sliders, I dunno.
They were done, though.

t

[eur04lif3]

Oh, and for the record, mine was apart because I heard "some" noise,
so whether the adjuster hastened the demise of the sliders, I dunno.
They were done, though.

t

Do you have pictures of your gears when you had to do the guides?
I'd like to compare them to my gears.

[bmwman91]

The tensioner piston should be good for 100k miles as long as you run decent quality oil and change it every 10k miles or less so you avoid gunk deposits. As for the tensioner rails and stuff, those are also supposed to last 100k miles, however MANY M42's out there are running either original parts or very old replacements. The vast majority of timing failures being seen right now are from a broken idler sprocket and a broken driver's side tensioner rail. A timing case rebuild is a bit of a pain, mostly because of the 240ft-lb crank damper bolt, but it is a straightforward weekend job otherwise (and $400+ in parts for a total overhaul).

As of right now, I recommend that anyone thinking about a timing case rebuild look into a late-model M42 case. It used an additional deflection rail instead of the stupid idler sprocket. As far as I am aware, it should be a direct swap into the E30 M42, but you should double check that. Alternatively, you can also run an M44 timing case which has bigger oil pump rotors, but you will need an adapter bracket to hold the crank sensor in place. That is what I am running, along with an M44 oil filter housing. Metric Mechanic can probably sell you a crank sensor bracket (it's where I got mine).

Regarding oil:
Mobil 1 15W-50 is highly recommended, it has the highest level of zinc & phosphorus you can find in a non-race oil, and our flat-tappet lifters really do need it. The only oil that did better in some tests by Metric Mechanic was Castrol 10W-60 TWS, which I am running now, but I will be switching back to M1 15W-50. The Castrol stuff is $17 per Liter, and holy shit it leaks through paper gaskets like CRAZY. I am losing about a Liter of the Castrol stuff per 1000 miles on a newly built engine with under 5k miles on it. Granted, at this rate I don't ever actually need to change the oil lol, just the filter, but it is annoying to have a mess in my driveway! Anyway, I guess that the Castrol oil is known for leaking in older engines because it was intended for use in new M-car engines that use metal gaskets and stuff.

[eur04lif3]

The tensioner piston should be good for 100k miles as long as you run decent quality oil and change it every 10k miles or less so you avoid gunk deposits. As for the tensioner rails and stuff, those are also supposed to last 100k miles, however MANY M42's out there are running either original parts or very old replacements. The vast majority of timing failures being seen right now are from a broken idler sprocket and a broken driver's side tensioner rail. A timing case rebuild is a bit of a pain, mostly because of the 240ft-lb crank damper bolt, but it is a straightforward weekend job otherwise (and $400+ in parts for a total overhaul).

As of right now, I recommend that anyone thinking about a timing case rebuild look into a late-model M42 case. It used an additional deflection rail instead of the stupid idler sprocket. As far as I am aware, it should be a direct swap into the E30 M42, but you should double check that. Alternatively, you can also run an M44 timing case which has bigger oil pump rotors, but you will need an adapter bracket to hold the crank sensor in place. That is what I am running, along with an M44 oil filter housing. Metric Mechanic can probably sell you a crank sensor bracket (it's where I got mine).

Regarding oil:
Mobil 1 15W-50 is highly recommended, it has the highest level of zinc & phosphorus you can find in a non-race oil, and our flat-tappet lifters really do need it. The only oil that did better in some tests by Metric Mechanic was Castrol 10W-60 TWS, which I am running now, but I will be switching back to M1 15W-50. The Castrol stuff is $17 per Liter, and holy shit it leaks through paper gaskets like CRAZY. I am losing about a Liter of the Castrol stuff per 1000 miles on a newly built engine with under 5k miles on it. Granted, at this rate I don't ever actually need to change the oil lol, just the filter, but it is annoying to have a mess in my driveway! Anyway, I guess that the Castrol oil is known for leaking in older engines because it was intended for use in new M-car engines that use metal gaskets and stuff.

Thanks for all this info.

My car's PO used 0W-40 Mobil 1 during his ownership, and i continued to use till now. And like you said, loves to leak through the paper gaskets.

Do you recommend i switch to 15W? Would it harm anything?

[bmwman91]

The owner's manual calls for 20W-50 under most normal environmental conditions, so I would imagine that 15W-50 is no problem at all. Mobil 1 10W-40 has decent levels of zinc & phosphorus, so I would recommend that over 0W-40. Run the 15W-50 in months when it is above freezing and 10W-40 during winter months if you want. I run the heavier stuff year-round, but it rarely gets below freezing here.

[eur04lif3]

The owner's manual calls for 20W-50 under most normal environmental conditions, so I would imagine that 15W-50 is no problem at all. Mobil 1 10W-40 has decent levels of zinc & phosphorus, so I would recommend that over 0W-40. Run the 15W-50 in months when it is above freezing and 10W-40 during winter months if you want. I run the heavier stuff year-round, but it rarely gets below freezing here.

According to this Mobil 1, 0w-40 has 1000 PPM of Phosphorus and 1100 PPM of Zinc which is the same as 10W-40.
The benefit going to 15W-50 is an extra 200 PPM of of Phosphorus and 300 PPM of Zinc, that's quite a bit more...especially if it helps reduce/eliminate my oil leaks!

Question now is, would it be better to go to 0W-40 or 10W-40 in the winter, as their additives are the same.

[bmwman91]

I'd say 10W-40 over 0W-40, mostly because of the fact that our engines use flat tappets. The slightly heavier cold-weight may be helpful during cold starts since that is when mechanical wear is going to be worst. Metric Mechanic did some oil life tests, and basically the two best performers were Castrol 10W-60 TWS and Mobil 1 15W-50. The M1 15W-50 lasted like 6x as long as the next-best one, and the Castrol stuff lasted twice as long as the M1. However, the Castrol oil seems to be far more cost and trouble than it is really worth.

I learned the hard way about using the "wrong" oil, so I guess I am extra paranoid about it. When I was breaking in my new engine I ran some Pennzoil 10W-40 dino oil for the first 1k miles or so (50 miles of initial break in, then changed it out with some fresh stuff and ran it for another 950 miles). Here's the result.

http://bmw.e30tuner.com/images/my318is/pic/deadspring/int_c1.jpg

http://bmw.e30tuner.com/images/my318is/pic/deadspring/int_c2.jpg

http://bmw.e30tuner.com/images/my318is/pic/deadspring/int_c3.jpg

http://bmw.e30tuner.com/images/my318is/pic/deadspring/int_c4.jpg

Granted, the M1 10W-40 synthetic is better stuff by a long shot, but I will forever be afraid of lower-weight oil in a flat tappet engine with hot cams. The stock cams are probably fine since they have low enough lift that the noses don't run up & over the edge of the tappets. These were 272/258 cams with 11.4 & 11.2mm lift.

One other thing...never start the car with the clutch pushed in. As most of you know, the stock thrust bearing on the crank is only a half-shell, and the M42 is well known for shredding it. Starting the car with the clutch pressed in means loading that half-bearing up with a few hundred pounds of force with zero oil pressure and then spinning the engine. Don't do it!

[roguetoaster]

One other thing...never start the car with the clutch pushed in. As most of you know, the stock thrust bearing on the crank is only a half-shell, and the M42 is well known for shredding it. Starting the car with the clutch pressed in means loading that half-bearing up with a few hundred pounds of force with zero oil pressure and then spinning the engine. Don't do it!

Interesting, never thought of that before. Your tip also (seemingly) helped my M30 powered E28 car crank over this nice cold AM. As usual the wise bmwman91 has something to teach us!

[bmwman91]

Thanks for the kind words. I actually learned about the "don't press the clutch when starting" thing from even more knowledgeable guys on M42Club a few years ago. There's always something new to learn!

[word is bond]

I actually didn't know that either - thanks for the tip. In a semi-related note, what's your guys opinions on leaving the car in gear while parked? Only on hills? All the time?