Crank without starting the engine?

[kyrix1st]

Just out of curiosity...

Does our E92 have what's called "cranking the engine" to build oil pressure like DB9?

[TrueToBMW]

Great question, wouldn't mind knowing this myself.

[mapster37]

not an option like the Austin Martin. but you could always pull the fuse for the fuel pump and crank the engine

[Timujin]

Great feature.

[kyrix1st]

I guess one "analog" way would be to take out fuel pump relay and crank the engine.

[Scharbag]

Are we sure that cranking RPM on an S65 will actually build enough pressure to cause oil to flow throughout the entire engine?

On another note, my buddies 1972 240Z has a forced pre-lube on his 3L high compression engine with a dry sump. Sounds so cool. Smells cool because it runs on 100+ octane only... Also sounds cool when running due to triple Mikuni carbs... But I digress.

Seriously though, does anyone know if the S65 pump builds enough pressure to cause reasonable oil flow when cranking?

Cheers,

[kyrix1st]

Originally Posted by Scharbag

Are we sure that cranking RPM on an S65 will actually build enough pressure to cause oil to flow throughout the entire engine?

On another note, my buddies 1972 240Z has a forced pre-lube on his 3L high compression engine with a dry sump. Sounds so cool. Smells cool because it runs on 100+ octane only... Also sounds cool when running due to triple Mikuni carbs... But I digress.

Seriously though, does anyone know if the S65 pump builds enough pressure to cause reasonable oil flow when cranking?

Cheers,

Good question. Thinking of adding an oil pressure switch should it be the case.

On the other hand, I noticed that it takes longer to crank up a cold engine (after about a month) even with fully charged battery. Maybe the DME detects last time the engine was started and builds the pressure on its own?

[GtiGyver]

Whats the difference between cranking the engine through the starter motor and letting the pressure build up using the engine power itself? I don't see how this could reduce wear.

How about an auxiliary electric oil pump that runs before you crank the engine?

[dsjr2006]

Originally Posted by GtiGyver

Whats the difference between cranking the engine through the starter motor and letting the pressure build up using the engine power itself? I don't see how this could reduce wear.

How about an auxiliary electric oil pump that runs before you crank the engine?

Rotating the engine using the starter does not produce anywhere near the same forces as combustion.

[Helmsman]

Originally Posted by dsjr2006

Rotating the engine using the starter does not produce anywhere near the same forces as combustion.

And surely the RPM must be lower when cranking then the immediate 1000 ish at cold start?
I actually tryed this the other day after the car been sitting for 2v. I had no of the usual (vanos?) "flutter" this time which may be an inducation it works to pre lubricate a little. Not sure but doesn't hurt to try.

[jvictormp]

Could someone post a picture of the fuel pump relay in the board?

And what about fault codes, will it throw any?

[doogee]

Easier to pull the fuse.

[smyles]

Moot unless you're starting an engine that hasn't run for years. And even then you want to rotate it for other reasons than oil pressure.

[da jemster]

These are steps of the S65 bearing installation from ECS Tuning.

[Scharbag]

Originally Posted by Scharbag

Are we sure that cranking RPM on an S65 will actually build enough pressure to cause oil to flow throughout the entire engine?

On another note, my buddies 1972 240Z has a forced pre-lube on his 3L high compression engine with a dry sump. Sounds so cool. Smells cool because it runs on 100+ octane only... Also sounds cool when running due to triple Mikuni carbs... But I digress.

Seriously though, does anyone know if the S65 pump builds enough pressure to cause reasonable oil flow when cranking?

Cheers,

As I said before, does anyone know if the S65 oil pump will actually build pressure when cranking? Regardless, unless your bearings are dryer than a popcorn fart, there is no need to pre-oil modern engines with modern oils.

But, if you reeeaaaalllyyyy want to crank and not fire, perhaps you can also use ISTA-d and put the car in compression checking mode... Total waste of time but hey, more power to ya.

Cheers,

[Scharbag]

Originally Posted by da jemster

These are steps of the S65 bearing installation from ECS Tuning.

And TIS simply says lubricate bearings and assemble engine.

If starting stresses and engine sooooo badly, then what will happen to all of the vehicles with that annoying auto-start "feature"?

[smyles]

The only reason to crank engine w/o starting after RB replacement (or any other significant repair) is to make sure you haven't majorly messed up something, as you can't turn it over manually like during engine-out overhauls.

[jayzbird]

Originally Posted by Scharbag

And TIS simply says lubricate bearings and assemble engine.

If starting stresses and engine sooooo badly, then what will happen to all of the vehicles with that annoying auto-start "feature"?

It’s cold start where the oil film has had enough time to shear away, or after an oil change when it takes a couple seconds to reprime the oil pump that is the concern. I’ve done this on occasion (never on the M) after oil changes, and have been able to see oil pressure build on the gauge. It does diminish that disconcerting knocking sound when you first startup after an oil change. But it takes a good 5-10 seconds of cranking.

[Scharbag]

Originally Posted by jayzbird

It’s cold start where the oil film has had enough time to shear away, or after an oil change when it takes a couple seconds to reprime the oil pump that is the concern. I’ve done this on occasion (never on the M) after oil changes, and have been able to see oil pressure build on the gauge. It does diminish that disconcerting knocking sound when you first startup after an oil change. But it takes a good 5-10 seconds of cranking.

The S65 has been show to take about 2 seconds to produce nominal pressure. There is no need to pre oil.

Oil will never completely flow away from bearings/bushings and leave them "dry". The rattle that you hear on cold start is the timing chains and guides due to loss of tension. It will not cause any damage.

Cheers,