Cylinder bank numbering

Before I replace the wrong O2 sensor, would somebody please be kind enough to confirm that BMW numbers their V8 cylinder banks 1 to 4 right side and 5 to 8 left side?

Reply to
Dean Dark
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No 1 is certainly on the right, but if the numbering is similar to other V8's, it's probably odd No's to the right and even No's to the left. Ie. 1 3 5 7 on the right and 2 4 6 8 on the left. Mike.

Reply to
Mike G

The correct question is, Bank 1 Left or Right?

I've always understood Bank 1 to be on the left side when sitting in the Driver's Seat.

Reply to
Jeff Strickland

Thanks for that. Fairly extensive googling fails to give me a definite answer, and I know that there isn't a common standard for cylinder numbering of V engines. I'll go with the right side O2 sensor, and see what happens.

Reply to
Dean Dark

I'd always thought looking at the front of the engine, odds on the right was the most common. Ie, No 1 is at the front of the car, US driver's side.

Reply to
Dave Plowman (News)

Try googling for the distributor wiring.

Reply to
R. Mark Clayton

Has any BMW V-8 got a distributor - apart from those of many years ago?

Reply to
Dave Plowman (News)

Kinda depends whether you're looking at it from the front of the car facing the rear or drivers seat facing forwards :-)

Reply to
SteveG

I'm looking for bank numbering. I'm not sure what the firing order has to do with it.

In spite of everything, I'm going with bank 1 being on the right. I think it's a good bet and if I'm wrong, then I'll just have to get under the damned car again and swap it.

Reply to
Dean Dark

Well, according to Bentleys, No1 cyl is definitely on the right when facing the front of the engine. Dunno what others are on about but AFAIK cylinder numbering 'always' starts from the front of an engine. The front being the end with the pulley for the ancilliaries. Fan, alternator etc. Mike.

Reply to
Mike G

Those weren't insults, believe me.

I just found that the ETK parts manual numbers the cylinders 1 to 4 on the right side and 5 to 8 on the left side. That matches the fault code descriptions of "cylinder bank 1 - 4" and "cylinder bank 5 - 8," so I think that's what I'll go with.

Reply to
Dean Dark

Now the only question is, which side is left and which is right. The left side of the motor is on the left side of the car when sitting in the driver seat, or standing at the back and looking forward. The driver's door is the left door, and so on. The left side of the motor is NOT the left side as you stand at the front of the car and look into the engine bay.

1 to 4 is normally on the left side, and 5 to 8 on the right.
Reply to
Jeff Strickland

Well, according to the ETK, 1 to 4 cylinders are on the right and 5 to

8 are on the left. The four exhaust manifolds each go to cylinders 1 & 3, 2 & 4 on the right, and 5 & 6 and 7 & 8 on the left. My inclination would be to number the cylinders in crankshaft order from front to back, but that doesn't seem to be the way that BMW does it.

Oh, and I'm assuming there that you wouldn't have the same confusion over which is the front and back of the car as you possibly might seem to have over which is the left and the right :-)

Reply to
Dean Dark

There is only one left, and one right, when referring to a vehicle.

Left and right are ALWAYS from the driver's seat.

The LEFT side of a vehicle in the US usually contains the steering wheel. The LEFT side of a vehicle in Great Britain usually contains the passenger seat.

When one is standing at the front of the car (why, oh why, did BMW go away from the rear opening bonnet/hood?), the LEFT side of the car is still the side that has the steering wheel in the US, or the passenger seat in the UK. Yes, you smart arses, there are exceptions if there is a RHD car in America or an LHD in the UK.

The easy way to remember banks, and/or cylinder numbering in a BMW is this. What side of the car did you need to stand on to remove the spark plugs from a 1970's 4 or 6 cylinder BMW? The RIGHT hand side. The cylinder number is

1 to 4, or 6, starting at the front. So, cylinder number 1 is the forward most cylinder on the RIGHT hand side of the car. Go back from there. When you run out of cylinders, move to the LEFT side. The even/odd numbering system is an American V8 trait that has probably made it's way into various European models, but not BMW.

V8, cylinders 1 through 4 are the RIGHT bank, cylinders 5 through 8 are the LEFT bank. V12, 1-6 RIGHT, 7-12 LEFT.

To add a little confusion, in a 6 cylinder car, if there is a reference to Bank 1, and Bank 2, bank 1 is the first 3 cylinders, bank 2 is the back 3 cylinders.

Hope this helps.

Brett Anderson KMS - Koala Motorsport

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Reply to
KMS - Brett Anderson

I agree that there is only one left and one right. The poster I was responding too seemed to think that the cylinders were numbered as from standing in front of the car and leaning over the grill.

I have to disapute this. As I sit here and consult my Motor Manual AND my Factory Shop Manual for my Jeep, it is clearly shown that the #1 cylinder is the front left.

I agree there are variances of numbering the odds all on the left and evens on the right (GM Style), and sequential numbering with 1 to 4 left and 5 to

8 right, (Ford Style) but the #1 is always the front left, and is always the front on an inline motor (either 4 or 6, or 8 for that matter -- yes, there was once an Inline 8). I am not aware of any motor that numbers the #1 on the front right. Please provide a cite if this is not accurate.

That would be an Inline 6. The V6 shares the Bank 1 and Bank 2 numbering conventions with the V8 motors.

Reply to
Jeff Strickland

I'm more than happy with you doing that.

The truth may upset you, but you'll doubtless be happier in your newfound ostrich-head-in-the sand little world where you don't see or hear anyone bursting your bubbles.

*Now* you can put me in your kill file...
Reply to
Dean Dark

OK. Insert BMW in front of V8 in my above text. In fact, insert it in front of everything I said. Sorry, as this is a BMW group, and the question was BMW related, I didn't see the need to put the BMW part in. I have no interest, and no knowledge about other makes.

#1 cylinder on a BMW V8 or a BMW V12 is the RIGHT front cylinder. Always, no exceptions.

Again, as BMW has never produced a V6, the thought of clarifying this never entered my head, but you are correct.

Thanks

Brett Anderson KMS

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Reply to
KMS - Brett Anderson

Agreed for a vehicle., but AFAIA left and right of and engine always refers to when you're facing the pulley end, or front of the engine. Means there's no confusion when it comes to transverse mounted engines. Mike.

Reply to
Mike G

That's okay, I was thinking that cylinder numbering convention was pretty universal, it did not occure to me that the metric system played a role in changing how the cylinders get numbered.

I'm good with that. I didn't know it, but ...

Reply to
Jeff Strickland

That would be incorrect. The left side of the motor is on the left side of the car.

Reply to
Jeff Strickland

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