M30 front crankshaft seal time....

[Bellicose Right Winger]

and I'll have to make a holder to get the nut off. Does anyone have an M30 crank pulley in the parts bin? I'm looking for a volunteer to measure the bolt circle.Thanks.

Paul Shovestul

[Jeff N.]

Hi Paul - I may have one. Send me an IM to remind me and explain exactly what you need.

I can check later Monday PM or Tuesday

[Anthony (M5 in Calgary)]

and I'll have to make a holder to get the nut off. Does anyone have an M30 crank pulley in the parts bin? I'm looking for a volunteer to measure the bolt circle.Thanks.

Paul Shovestul

No, but I do have the seal and gasket kit if you need them.

[pundit]

Are you absolutely certain the crankshaft seal is leaking?
One of the M30's idiosyncratic oil leaks (which is often mistakenly attributed to the crank seal) is the loosening of the larger of the two bolts that retain the crank angle sensor bracket.

Oil working it's way out past the thread of the bolt leaks out all over the front of the engine and onto the crank pulley where it is flung off giving the impression the seal is leaking.

[Bellicose Right Winger]

Jeff,
That would be great. I need the diameter of the circle that passes thru the center of all (6) bolt holes to the nearest 1/16" as shown in attachment.

Edit: Make that (8) holes.

Paul Shovestul



Hi Paul - I may have one. Send me an IM to remind me and explain exactly what you need.

I can check later Monday PM or Tuesday

[Bellicose Right Winger]

Thanks Pundit,
I'll take another look and keep my fingers crossed you're right, but the timing chain cover near the CPS looked pretty dry.

Paul Shovestul



Are you absolutely certain the crankshaft seal is leaking?
One of the M30's idiosyncratic oil leaks (which is often mistakenly attributed to the crank seal) is the loosening of the larger of the two bolts that retain the crank angle sensor bracket.

Oil working it's way out past the thread of the bolt leaks out all over the front of the engine and onto the crank pulley where it is flung off giving the impression the seal is leaking.

[Bellicose Right Winger]

Anthony (M5 in Calgary),
I'm all set with the seal, but I don't think you need a gasket to change the front crank seal. Is your the rear crank seal & carrier gasket by any chance?

Paul Shovestul


No, but I do have the seal and gasket kit if you need them.

[Kalevera]

That seal is a bear to do in the car. Practically easier to remove the lower timing cover off. It requires a lot of pressure and care to get the new seal in correctly.

Like pundit said, be sure that's what is leaking before attempting...

best, whit

[Anthony (M5 in Calgary)]

Anthony (M5 in Calgary),
I'm all set with the seal, but I don't think you need a gasket to change the front crank seal. Is your the rear crank seal & carrier gasket by any chance?

Paul Shovestul

Nope. Front seal and timing case gaskets only. Purchased when I thought I had a leaking front seal. Turned out to be the CPS bracket bolts a la Pundit...

[Bellicose Right Winger]

Interesting, I can always pull the cover if I get into trouble. I changed one 15 years ago in my E12 528i. Only memorable moment was feeling the spring in crankshaft while removing crankshaft nut with flex plate being locked. I didn't touch the timing cover. I wonder what's different?

Just re-checked the cps bracket and it's dry and tight. Too bad.

Paul Shovestul



That seal is a bear to do in the car. Practically easier to remove the lower timing cover off. It requires a lot of pressure and care to get the new seal in correctly.

Like pundit said, be sure that's what is leaking before attempting...

best, whit

[Bellicose Right Winger]

Thanks, Jeff!!!


Re: Crank pulley bolt circle
Here you go.

Inner diameter = inside to inside = 62mm
Outer diameter = outside to outside = 80mm
Estimated center to center = 70mm
bolt hole diameter = 8mm

Measurements on a m30 harmonic balancer, b35 motor. Measurements taken with a fine $12 set of plastic calipers.

Let me know if you have questions Paul!

Cheers!

Jeff