Oil pan ID etc.

Discussion in 'Airheads' started by TrailCruiser, Dec 10, 2014.

  1. TrailCruiser

    TrailCruiser Been here awhile Supporter

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    As I finally begin the teardown on my R75/7 winter project I wanted to get some input from those in the know on the oil sump that came on the bike. Here's a look...

    [​IMG]
    [​IMG]
    [​IMG]

    Using the most excellent info on the largiader.com site (LINK) this appears to be a Motoren-Israel aftermarket pan. I haven't had it off yet so I don't know if the pickup has been extended downward as it should be, will report back.

    A few questions and considerations:
    • Using the same site referenced above I appear to have the original stock dipstick with the "max" mark 260 mm from the base. What oil quantity should I be using and what level on the stick should represent full?
    • Is there a longer dipstick I should be using, and if so where would I get one?
    • I see that the kickstand crossbar is hitting the fins and understand that that is not good. I plan on having the machine shop at work use a ball end mill to relieve the fins for the crossbar, good idea?
    • Can I lift the engine out of the bike with this (or any) oil pan on? It's been so long since I pulled an airhead engine I can't remember the procedure or what must be disassembled.
    Any other advice about anything relating to this appreciated.
    #1
  2. Jim K in PA

    Jim K in PA Long timer Supporter

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    Before you mill the pan, check to make sure the pivots and stops on the center stand are not worn and allowing the cross brace to hit it.
    #2
  3. chasbmw

    chasbmw Long timer

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    My approach to the deepan deepan dipstick problem is to split the extra volume 50/50 between extra crankcase volume and extra oil and then fill the bike with a measured volume of oil say 2.75 litres and see where that falls on your dipstick.

    If you want to be really anal, you could turn over the engine a bit to fill all the normal places where oil might lurk such as rocker covers etc.
    Hope this helps.


    You might lower the cross bar a bit
    #3
  4. Bill Harris

    Bill Harris Confirmed Curmudgeon

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    On my '73 /5, I added a "3 Qt Sump" (deep oil pan) years ago and used an "A"-length dipstick to lower the oil level several millimeters so that the old-style breather was less prone to blowing oil out the breather pipe. The Oil Capacity is 2.75 L.

    --Bill
    #4
  5. gsd4me

    gsd4me 90% bluff Supporter

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    I'd be doing what Chas suggests. My bike recently got a sump spacer, which gives about another litre capacity. In my case we re-marked the dip stick and now use that as the full mark. It is a bit less than 500ml to the bottom mark and then there is as much if not more oil left as in the standard sump capacity.

    [​IMG]

    [​IMG]
    #5
  6. bmwrench

    bmwrench Long timer

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    This looks like a Huekerott pan, imported by Michael Bondy in the late '70s. Michael's family were the original east coast BMW importers. Inside you should find a spacer that lowers the pump pickup that is longer than the original. /7s have the longest stick available, although I like to replace them with the plastic handled one from 1981. The plastic handle allows you to check the level with a hot engine without getting burned.

    Yes, I would mill away some of the fins to clear the stand brace unless you're willing to relocate the brace.

    /7s have a better breather arrangement than the earlier bikes, so I would fill it to "max" and see how it works.
    #6
  7. TrailCruiser

    TrailCruiser Been here awhile Supporter

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    Thanks for the info guys. Anyone know if I can get the engine out of the frame with that pan still on there?
    #7
  8. eight90eight

    eight90eight Been here awhile

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    Regardless of what large pan is put on any airhead, the original dipstick should still show oil level in relation to the crank swing.

    2 1/2, 2 3/4, 3, or more, all the extra oil rests lower, not higher.

    I got a Mac on my 900, and use the original dipstick the show where the oil level is in the crankcase in relation to the crank, as designed for that model.

    Check to see if the oil pickup is lowered as per that pan's design.

    What a larger pan gives is one of two things, depending on which you want. Either more volume of oil, or more volume of air, in the crankcase, maybe lower temps, in either scenario depending on how far and long open the throttle.

    Less pressure, less blow by the relief flapper/reed valve into yer right cylinder, and less pressure on the bottoms of the pistons as they squish together on each revolution.

    More oil?, guess you get more oil! Considering how often airheads get their oil changed, can't see much of a benefit to adding more oil to two quarts, that hardly get used before they're dropped in the recycling center.

    I think it's critical that if a deep pan is used, that you have the added extension on the pickup. The stock pickup distance should maintained. I.e., the distance between the pickup and the pan's bottom. In my humble opinion, pays the man takes yer chances.
    #8
  9. TrailCruiser

    TrailCruiser Been here awhile Supporter

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    Following up on this, here are pics of the inside...

    [​IMG]
    [​IMG]

    The bottom of the oil pickup is about .625" above the bottom of the sump, and you can clearly see the spacer in the oil pickup. My assessment is therefore that all looks good in there and that I'll reinstall it and I'll play with the oil level to get both more air volume and more oil capacity, effectively split the increase between them. What I don't know is where that is on the dipstick but I guess I can figure that out with some experimentation. Oh, and I'm still going to have a relief machined into the fins so as to avoid contact with the kickstand.

    Looks pretty clean and normal in there, anyone see anything amiss? I checked the torque on the pickup bolts as well, all good.
    #9
  10. bmwrench

    bmwrench Long timer

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    It's worthwhile to Loctite the pickup bolts.
    #10
  11. Kt-88

    Kt-88 I like everything.

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    +1 on that. I had my screen come off on my last deep sump bike and never knew until I dropped the pan to get rid of the silicone gasket the PO had on there. Not the happiest discovery.
    #11
  12. elmontanero

    elmontanero Practicing...

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    This is a timely topic. Picked up a /5 a few days ago and have a leak at the pan. Here's the pan:
    [​IMG]
    [​IMG]
    Any guidance or direction on who created this one? Fits well under the centerstand but also limits having oil in there. I'm not sold that the pan is leaking, the pushrod seals aren't pristine either.
    #12
  13. Jim K in PA

    Jim K in PA Long timer Supporter

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    Looks like a MAC aftermarket, same as I have on Otto. Pics of mine in my thread linked in my sig (page 6).
    #13
  14. elmontanero

    elmontanero Practicing...

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    yep... looks like the same one. Thanks! I'm having fun exploring the new bike. Seems like there's many opinions about deeper pans.

    I'm tempted to put the original pan as the bike won't be doing much long distance duty. But the Longer one looks the business.
    #14
  15. supershaft

    supershaft because I can

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    I suspect the silicon gasket and its installation had more to do with your pickup coming off more than anything else. I know from experience that those pickup bolts stay tight forever without loctite IF you use the right gasket and tighten them down properly. The pickup coming loose is a very, very rare deal in my experience.

    More important advice IMO is to heat such fasteners up real good working on a strange to you engine before loosening them in case some moron has red locktited them. The stuff WILL strip threads otherwise! If it was installed properly anyway.
    #15
  16. Kt-88

    Kt-88 I like everything.

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    The pickup used standard gaskets, the pan itself was using the silicone.
    #16
  17. Renner

    Renner combustophile Supporter

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    I like the baffled, -995 pan but a stock centerstand's upper crossbrace won't clear its back edge.
    My /5 has a Reynolds c'stand which clears that pan. On another -995 pan equipped bike I'm considering relocating the stock centerstand's upper crossbrace.

    I gather you have the stock pan in the box of spares that came with your /5. If not, I have one you're welcome to.
    #17
  18. TrailCruiser

    TrailCruiser Been here awhile Supporter

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    Good advice, never easier than right now. I'm inclined to use blue Locktite, any real reason for red?

    Also, what sealer are folks using with the pan gasket? And would it be the same sealer for the cylinders when I reinstall them?
    #18
  19. TrailCruiser

    TrailCruiser Been here awhile Supporter

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    The pivots are fine, I'll post a pic here after I've had a groove relieved across it for the kickstand crossbar.
    #19
  20. therealbatman

    therealbatman "Godfather"

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    I used blue locktite and no sealant on the oil pan gasket...no leaks.
    #20