Engine to Gearbox Gasket?

[Boxer_Bolshie]

My first question: is there a gasket between the gearbox and engine?


Next: I have search high and low and though I have found gasket kits for xyz, but I think it would be helpful if there was a list of ALL gaskets needed for a complete overhaul for our R65 models.

[Bob_Roller]

There's no gasket between the engine and gearbox .

As far as I know, there are no kits with all of the gaskets for an R65 and I have never seen a listing for all of the gaskets/seals  .

Pretty much need to get into the parts diagrams and find them yourself .

[nhmaf]

There are alot of gaskets.  It would not be cheap.
I just ordered a set of 4 pushrod tube seals, a pair of head gaskets and a set of large and small o-ring sets for the cylinder bases and this came to just over $70.

You've got gaskets in the carbs, timing case cover, valve covers, and numerous places in the driveline. Plus oil pump cover seals, and rear main oil seal and flywheel o ring, and various seals in the gearbox.   There are grease seals in the front and rear wheels and other bearing locations.  You really only want to deal with stuff that needs to be replaced when it needs replacing.

One thing that I did notice (and bought) was that the EUBMW guys were selling crush washer kits with aluminum crush washers in a baggie that covered all the usual drain plug locations on the bike for ~ $3 at the last BMWMOA rally.  That was handy.

[Boxer_Bolshie]

I am pretty good on gaskets but I think it might be helpful if there was at least a list of gaskets and their corresponding part number so if someone was doing a restoration they could use it as a check list.

[Boxer_Bolshie]

Thanks Bob!  That's kinda what I thought but it just seemed odd that almost all metal to metal parts get some sort of gasket or at least washer but two of the biggest and most important parts.  

I know there's no fluid between the two but neither is there between the timing cover and case

[Bob_Roller]

I've put a little 'skin' of sealant between the gearbox and engine, as I didn't like the two metal parts coming together without a gasket of some sort between them .

[Rob Valdez 79 R65]

I've put a little 'skin' of sealant between the gearbox and engine, as I didn't like the two metal parts coming together without a gasket of some sort between them .

I would NEVER do this if you are using the stock (and only) ground (earth) connection from the battery to the rear of the gearbox.  It needs that contact to complete the ground to the bike!

A lot of people relocate that stock ground point anyway, as it connects via a fairly fragile, yet critical fastener.

[Bob_Roller]

I don't think it's an issue, due to the four fasteners that hold the transmission to the engine .

More than enough metal to metal contact there to provide an electrical path back to the battery .

[nhmaf]

There isn't a gasket between the engine and transmission because their position and alignment is important for the proper operation of the gearbox.  If a gasket were there, it's varying degree of compression would cause variation in how far the input shaft engages with the clutch disk spline, and the clearance thereof.

There is a fair amount of threads for the passing of electrical current, but I personally don't like relying on threads to carry current.  I also sometimes put some antiseize on fastener threads into aluminum alloy.   I keep the cases clean of any sealant in the gearbox-engine interface, though I will also admit that oxidation, etc. probably  reduce the effectiveness of the interface of the two lumps of metal being held together.

[Bob_Roller]

I've checked the resistance between the engine and transmission and get 0 ohms .

I've been doing this for the last 14 years, no electrical problems yet .

[Air4Life]

You could add a jumper or two across the span and tell everyone its got the Roller booster kit.     Very expensive add on.

[Bob_Roller]

It would be quite easy to add a bonding wire/strap between the engine and transmission .

The lower left bolt on the transmission, has a nut on it, easy enough to put a jumper under the bolt head and the other end under the nut .