The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: marcmax on October 07, 2015, 03:56:48 PM

Title: Swapping Oil Pans
Post by: marcmax on October 07, 2015, 03:56:48 PM

Does anyone know the differences in airhead oil pans. I was told they all fit the same bolt pattern since they all attach to the same basic engine block. I want to swap to an R80gs or R100gs oil pan so I can mount a skid plate to the bottom. Those oil pans have threaded bosses to attach a skid plate to.

I have found some that are almost flat with the drain hole exiting from the bottom and some that are almost wedge shaped being very deep near the front and tapering down at the rear. Some with drain holes on the bottom and some with drain holes on the rear vertical face of the oil pan.

The oil pan on my R65LS is more like the wedge shaped ones, deeper near the front and tapers off to almost nothing at the rear with a bottom drain hole.

Mine looks like across between pic 2 and 3.

Any suggestions on what to swap to?

Title: Re: Swapping Oil Pans
Post by: Tony Smith on October 08, 2015, 05:59:33 AM

You can swap any /5 or later oil pan onto any /5 or later engine, you need two things:-

1/. The pan

2/. The correct length oil pickup (and bolts) and (depending on pan depth) the extension piece that extends the "depth' of the oil pickup

Buying a pan on spec without getting the oil pickup that goes with that pan leaves you with the annoying job of "whittling" an extension piece from a lump of alloy (The one I had to make for a friend's R100RS that he decided to mount a late model pan to I made using only a hacksaw, drill press and mill files - it took a day)

The first "interesting" part is deriving a way to measure how long the extension needs to be.

But if you get the oil pickup with the pan, no problems.  Although I do not believe that this would  ever be a problem with the R65 Ihave a nagging memory of having to donate my old and somewhat weary R100 centre stand to a friend who was fitting a big sump to an r50 or R60 as the cross piece on the the original stand was too high for the deeper sump - but it was a long, long time ago.

Title: Re: Swapping Oil Pans
Post by: marcmax on October 08, 2015, 07:27:29 AM

Thanks Tony. Quite a few of the ones I was looking at come with the pickup and all of the bits required to use it so I will stick with one of those.

Title: Re: Swapping Oil Pans
Post by: Barry on October 08, 2015, 12:24:36 PM

Except for the 4 square bosses, oil pan 2 looks like a 78-80 R45/R65 pan. 81-84 R45/R65 pans were deeper so more like Oil pan 3.