DIY: Cranking engine to prime oil gallery.
Results 1 to 16 of 16

Thread: DIY: Cranking engine to prime oil gallery.

  1. #1
    Join Date
    Mar 2019
    Posts
    32
    Likes (Given)
    0
    Likes (Received)
    24
    Downloads
    0
    Uploads
    0

    DIY: Cranking engine to prime oil gallery.

    This is a way of cutting the ignition and fuel to the engine so you can crank to prime the oil gallery prior to starting.

    Why do this? If you have done any engine work, the car has sat for a while without starting, or most commonly after an oil change. Changing the oil filter will empty the oil filter housing, so priming the system will have it fully lubricated immediately on start rather than having no oil pressure for the first few seconds with the associated metal on metal rattling.

    First thing is to shutdown the engine by pulling the fuel pump fuse. The engine will stop within a few seconds. Leave the fuse out. Fuel pump fuse is B5 on the left footwell panel. Tool to remove fuses is in the right footwell panel. Image below of fuse location. Note this is an approved procedure in the workshop manual to shutdown the engine and remove the fuel pressure from the fuel system.

    DIY: Cranking engine to prime oil gallery.-fuse-fuel-pump-jpg

    When you complete your work, and you intend to start the engine, remove the ignition fuse in the right rear part of the boot/trunk. You don’t need to remove the lining, just pull it back to expose the fuse panel and remove the fuse shown below. This is the circuit that provides high power to the spark plugs. The signal from the ECU for spark plug firing will still occur, but the high power source to create the spark will not be available.

    DIY: Cranking engine to prime oil gallery.-fuse-ignition-jpg

    When you now crank the engine, the spark plugs won’t fire and there will be no fuel injected.

    Turn the key like you are trying to start the car. It will crank for about 5 seconds prior to it stopping on its own. Turn key to off and do it again. I normally do this twice (about 10 secs or cranking) for a simple oil change to ensure the oil gallery is full. If you were doing an engine rebuild, a lot more would be required. You should hear a small increase in RPM when cranking when oil is finally everywhere.

    Now replace both fuses. When starting the car, turn the key to the first position for a few seconds (this will prime the fuel system) and then turn the key to start. It should start with no unusual noises. No codes should be recorded in the ECU.

    I did this on my recent oil change and was very happy with the softness of the start. It was like it had been shutdown only moments earlier.

  2. Remove Advertisements
     

  3. #2
    Join Date
    Jul 2013
    Location
    N/A
    Posts
    764
    Likes (Given)
    384
    Likes (Received)
    268
    Downloads
    14
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    I think this is really interesting — thanks a lot for posting it!

    I do have a question though. What is the problem that you are trying to solve for here? Whether you crank with the starter motor or run with the ignition system active aren’t you basically turning over the engine sans oil the same number of revolutions? Is there a concern about the additional (brief) higher RPM under ignition or is there something about fuel ignition itself with only film oil present that is problematic?

    Thanks again for posting.

  4. #3
    Join Date
    Mar 2019
    Posts
    32
    Likes (Given)
    0
    Likes (Received)
    24
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    Quote Originally Posted by canux View Post
    I think this is really interesting — thanks a lot for posting it!

    I do have a question though. What is the problem that you are trying to solve for here? Whether you crank with the starter motor or run with the ignition system active aren’t you basically turning over the engine sans oil the same number of revolutions? Is there a concern about the additional (brief) higher RPM under ignition or is there something about fuel ignition itself with only film oil present that is problematic?

    Thanks again for posting.
    It's just getting oil through the system and everything fully lubrication prior to firing the engine. Initial start without full lubrication is undesirable due to metal on metal contact. When turning over the engine the oil pump is turning but without the load of the engine running. Then when you do start the engine is fully lubricated. Most high performance engines will always start in this way. Listen to an F1 engine start. They turn over on the starter for a good while (waiting for full oil pressure) prior to starting. If the engine is cold, you generally get full oil pressure out of the pump where the engine is only turning at about 120 RPM when cranking.

    When you start the car normally it is actually doing this. It waits a couple of seconds to get oil around the engine a bit prior to firing (introduction of fuel and spark). This is assuming the oil gallery is already full. Unfortunately when you have done some maintenance and the oil gallery isn't primed, a few seconds of engine crank isn't sufficient to prime the system.

    I want to remove the spark and fuel for a few reasons.

    If only the spark is removed, there is going to be fuel washing the cylinder if not being burnt, which I would prefer to avoid as I want to keep it lubricated. Also, the exhaust is going to get a bunch of unburnt fuel in it.

    If you could stop the injectors completely that would be great, but the firing impulses from the ECU to the injectors don't have a common power supply through a fuse. They come directly from the ECU, so the only way to stop the fuel is to remove the pressure from the fuel pump. Unfortunately there is sometimes some residual pressure that might allow a bit of fuel to be injected and have the engine try and fire, hence removing the spark as well so avoid the possibilty of this.

  5. Remove Advertisements
    Planet-9.com
    Advertisements
     

  6. #4
    Join Date
    Aug 2016
    Location
    California
    Posts
    170
    Likes (Given)
    669
    Likes (Received)
    60
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    I really like this idea! However, I wonder, don't the engines in the 987.2 and 981 have multiple electric oil pumps? Could those pumps be triggered to run before even spinning the crankshaft after an oil change, or a rebuild?

    Something I do when changing the oil filter is to insert the filter into the housing and fill the housing nearly full with fresh oil before reinstalling it. This helps reduce the time it takes to reprime the oiling system after a change. Being able to run the oil pumps before turning the engine over would be very beneficial.

    Sent from my SM-N950U using Tapatalk
    2014 CS, Guards Red/Luxor Beige, Red Belts, Multi-function Steering Wheel, 14 way Seats, PDK, Sport Chrono, PCM, Infotainment with Bose, Park Assist, PS+, PDLS, SportTechno Wheels, and Fancy center caps

  7. #5
    Join Date
    Mar 2019
    Posts
    32
    Likes (Given)
    0
    Likes (Received)
    24
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    Quote Originally Posted by wagzhp View Post
    I really like this idea! However, I wonder, don't the engines in the 987.2 and 981 have multiple electric oil pumps? Could those pumps be triggered to run before even spinning the crankshaft after an oil change, or a rebuild?

    Something I do when changing the oil filter is to insert the filter into the housing and fill the housing nearly full with fresh oil before reinstalling it. This helps reduce the time it takes to reprime the oiling system after a change. Being able to run the oil pumps before turning the engine over would be very beneficial.

    Sent from my SM-N950U using Tapatalk
    I'm pretty sure there is no electric oil pump on this engine. I've looked at it extensively, and I've never seen a reference to an electric oil pump.

    You are correct on the idea of filling the OFH with oil reducing the time to prime. Not a perfect solution, and pretty messy with the location of the housing. It's very simple to do it like described above.

    The MA1.23/22 engines are a bit unique in that the OFH is at the top of the engine, but the housing points down. This allows you to fill the housing with oil like you describe. The housing on the 911 engine (identical in most other respects) points up and rearward so you wouldn't be able to. Some engines I've worked on have the OFH at the base of the oil pan so they self prime the moment you fill with oil.

  8. #6
    Join Date
    Oct 2017
    Location
    Georgia
    Posts
    80
    Likes (Given)
    4
    Likes (Received)
    28
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    All you need to do is push throttle to the floor and turn key. The car will recognize the request and just turn over and not start. After a couple of goes like that, just take foot of gas and it will start normally.

    Quote Originally Posted by jjrichar View Post
    This is a way of cutting the ignition and fuel to the engine so you can crank to prime the oil gallery prior to starting.

    Why do this? If you have done any engine work, the car has sat for a while without starting, or most commonly after an oil change. Changing the oil filter will empty the oil filter housing, so priming the system will have it fully lubricated immediately on start rather than having no oil pressure for the first few seconds with the associated metal on metal rattling.

    First thing is to shutdown the engine by pulling the fuel pump fuse. The engine will stop within a few seconds. Leave the fuse out. Fuel pump fuse is B5 on the left footwell panel. Tool to remove fuses is in the right footwell panel. Image below of fuse location. Note this is an approved procedure in the workshop manual to shutdown the engine and remove the fuel pressure from the fuel system.

    DIY: Cranking engine to prime oil gallery.-fuse-fuel-pump-jpg

    When you complete your work, and you intend to start the engine, remove the ignition fuse in the right rear part of the boot/trunk. You don’t need to remove the lining, just pull it back to expose the fuse panel and remove the fuse shown below. This is the circuit that provides high power to the spark plugs. The signal from the ECU for spark plug firing will still occur, but the high power source to create the spark will not be available.

    DIY: Cranking engine to prime oil gallery.-fuse-ignition-jpg

    When you now crank the engine, the spark plugs won’t fire and there will be no fuel injected.

    Turn the key like you are trying to start the car. It will crank for about 5 seconds prior to it stopping on its own. Turn key to off and do it again. I normally do this twice (about 10 secs or cranking) for a simple oil change to ensure the oil gallery is full. If you were doing an engine rebuild, a lot more would be required. You should hear a small increase in RPM when cranking when oil is finally everywhere.

    Now replace both fuses. When starting the car, turn the key to the first position for a few seconds (this will prime the fuel system) and then turn the key to start. It should start with no unusual noises. No codes should be recorded in the ECU.

    I did this on my recent oil change and was very happy with the softness of the start. It was like it had been shutdown only moments earlier.
    2013 Agate Grey Boxster S PDK

  9. #7
    Join Date
    Feb 2018
    Location
    NH
    Posts
    106
    Likes (Given)
    1
    Likes (Received)
    29
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by fsae99 View Post
    All you need to do is push throttle to the floor and turn key. The car will recognize the request and just turn over and not start. After a couple of goes like that, just take foot of gas and it will start normally.
    I would love to know where this is documented.
    Thanks!

  10. #8
    Join Date
    Oct 2017
    Location
    Georgia
    Posts
    80
    Likes (Given)
    4
    Likes (Received)
    28
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    Quote Originally Posted by MLCayman View Post
    I would love to know where this is documented.
    Thanks!
    I think all FI cars after 2010 do this, where it is actually documented not sure. I learned it in 2013 on the forum for my last car (Ford Focus ST), been using it ever since.
    I've had my boxster S for almost 2 years (put 39K miles on it) and have done 8 oil changes. I fill the oil filter housing about 3/4 full (so I don't spill oil) then use this method each and every time to get he oil primed.

    I promise you if you hold throttle to floor and turn key it will not start. If I get time latter I'll do video.

    Regards,
    Jim
    2013 Agate Grey Boxster S PDK

  11. #9
    Join Date
    Mar 2019
    Posts
    32
    Likes (Given)
    0
    Likes (Received)
    24
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    Quote Originally Posted by fsae99 View Post
    All you need to do is push throttle to the floor and turn key. The car will recognize the request and just turn over and not start. After a couple of goes like that, just take foot of gas and it will start normally.
    Thanks for this fsae. This is clearly a much more effective way of priming the system, and I will no doubt use this extensively in the future.

    The more I learn about this car the more I love it and the way Porsche design things. This is a very useful tool, not just for oil changes, but anytime you want to crank the engine prior to starting. Car sitting for many weeks without starting for example.

    I do have one question. When cranking by the method I used it stops the crank automatically after about 5 seconds. Does it do this using the method you describe, or does it allow you to crank for as long as you like?

    Thanks again.

  12. #10
    Join Date
    Feb 2018
    Location
    NH
    Posts
    106
    Likes (Given)
    1
    Likes (Received)
    29
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by fsae99 View Post
    Quote Originally Posted by MLCayman View Post
    I would love to know where this is documented.
    Thanks!
    I think all FI cars after 2010 do this, where it is actually documented not sure. I learned it in 2013 on the forum for my last car (Ford Focus ST), been using it ever since.
    I've had my boxster S for almost 2 years (put 39K miles on it) and have done 8 oil changes. I fill the oil filter housing about 3/4 full (so I don't spill oil) then use this method each and every time to get he oil primed.

    I promise you if you hold throttle to floor and turn key it will not start. If I get time latter I'll do video.

    Regards,
    Jim
    Jim:
    I guess I'd better give that one a try! A video would also be good if you are able.
    Thank you!

  13. #11
    Join Date
    Jul 2013
    Location
    N/A
    Posts
    764
    Likes (Given)
    384
    Likes (Received)
    268
    Downloads
    14
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    Quote Originally Posted by MLCayman View Post
    Jim:
    I guess I'd better give that one a try! A video would also be good if you are able.
    Thank you!
    This has been the case for most EFI cars for as long as there have been EFI cars to the best of my knowledge. The purpose of this “feature” is to “un-flood” a flooded (fuel) car.

    This was the method used by carburated cars and manufacturers simply programmed the same feature into EFI cars when they developed them because everybody already knew how to do it.

    However, I thought that this only halved the fuel flow to the engine, not cut it completely. It makes more sense to cut the fuel off completely as long as you know that after a certain amount of cranking you need to start again without depressing the accelerator.

    Interesting.

  14. #12
    Join Date
    Mar 2019
    Posts
    32
    Likes (Given)
    0
    Likes (Received)
    24
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    Quote Originally Posted by fsae99 View Post
    All you need to do is push throttle to the floor and turn key. The car will recognize the request and just turn over and not start. After a couple of goes like that, just take foot of gas and it will start normally.
    I tried this yesterday and it definitely didn't work. I don't know what I did wrong, but the car started with much enthusiasm. I don't know what I did differently.

    Initial turn of the key with the pedal to the floor gave me the 'press the brake' message. When I then pressed the brake, had the accelerator to the floor and then turned the key it started immediately. Any ideas?

  15. #13
    Join Date
    Jun 2019
    Posts
    4
    Likes (Given)
    0
    Likes (Received)
    0
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    I am a newbie about to change my 2014/981 oil tomorrow and would like to hear a follow up to this last reply. And, not to hijack the thread but, speaking of oil change: is the oem drain plug magnetic? TIA, dlb

  16. #14
    Join Date
    Sep 2015
    Location
    Atlanta GA
    Posts
    992
    Likes (Given)
    78
    Likes (Received)
    281
    Downloads
    4
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    Quote Originally Posted by dlbehrns View Post
    I am a newbie about to change my 2014/981 oil tomorrow and would like to hear a follow up to this last reply. And, not to hijack the thread but, speaking of oil change: is the oem drain plug magnetic? TIA, dlb
    No it is not

  17. #15
    Join Date
    Aug 2016
    Location
    fl
    Posts
    725
    Likes (Given)
    29
    Likes (Received)
    119
    Downloads
    0
    Uploads
    0
    What happened when you didn’t push brake in, but accelerator to the floor?

  18. #16
    Join Date
    Mar 2019
    Posts
    32
    Likes (Given)
    0
    Likes (Received)
    24
    Downloads
    0
    Uploads
    0

    Re: DIY: Cranking engine to prime oil gallery.

    Quote Originally Posted by mrg02d View Post
    What happened when you didn’t push brake in, but accelerator to the floor?
    Nothing except the message on the MFD saying to press the brake.

  19. Remove Advertisements
     

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •