Checked FD - uh oh . . .

[Red_Hen]

Hi Gang,

My R65 may be taking a trip to Sedalia, MO - I checked the FD fluid and I couldn't see any indication of fluid.  I added about a bottle of Castrol 80/90 and now she's full to the brim.

I'll have to watch it - it is possible the "O' rings I just read in a recent post are kaput.  Hopefully I didn't do any damage to the FD unit by riding around with low oil.  Most of my trips on Tina are around town.  She seems to be running okay.

[Bob_Roller]

Do you have any indications of leakage from the final drive ?

How full is it, full to the small over flow port at the back of the final drive ?

[nhmaf]

+1 with Bob - it should only be filled up to the bottom threads in the fill/check port at the 9o'clock position (back edge) for the final drive.   If you overfill it, you will likely encourage seals to start leaking when the things heats up while driving on the highway.

It is rare, but not unknown, for the seal at the FRONT of the final drive to manage to leak fluid FORWARD into the drive shaft - this is usually most apparent when taking off the clamp of the rubber boot by the back of the transmission and seeing a cup of oil come out - normally there should only be ~120cc of oil in the drive shaft area... but, if you aren't seeing leaks out the final drive or inside the brake hub, that stuff has got to be going somewhere.

[Barry]

Hopefully I didn't do any damage to the FD unit by riding around with low oil.Most of my trips on Tina are around town.

As long as there was enough oil in there to wet the crown wheel it may not have come to any harm from low speed use. Best thing is to drain it and see if there is any debris on the drain plug.

I added about a bottle of Castrol 80/90 and now she's full to the brim.

What size bottle would that be? The total fill for your final drive is only 350cc. Oil can and does move about between the 3 transmission items but I wouldn't have thought as much as that. I've experienced it going from the drive shaft to the final drive but not the other way around.

[Red_Hen]

Thanks guys - I did not realize the fill hole is the 9 o'clock position - thought it had to go all the way to the top plug - I'll drain, measure 350cc's and refill.  I guess it may have been okay - I have a Clymers book which covers several model Airheads - I thought I read the gear oil was supposed to be filled to the top.

Barry - the bottles is one US Quart.  And no, Bob, there has not been any leakage.

[Red_Hen]

I drained the FD reservoir - there was more than 350cc's - the fluid was quite black - this is the bike that sat outside for a couple years - at any rate, the drain plug didn't have any metal shavings but did have some goo, which I cleaned.

I measured 348cc's and added 2cc's of Guard Dog, a Moly additive to the 80/90 Castrol Gear Oil - mixed it up and poured it in the reservoir.

Glad I'm a part of this group! Thanks Guys!

[Julio A.]

350cc? I thought is was 250cc's. Or was that only for the older type cardans?

[Red_Hen]

Hi Julio,

My Clymer book calls for 350cc's for an '82 year.

[Barry]

It's the 78-80 non ribbed type of final drive that takes 250cc and the level/filler plug arrangement is different too.

Ken, about the oil coming out black.  That suggests it might not have been changed in a long while. Only wear particles should discolour the oil, excepting water contamination which will turn it milky brown. So one indicator that all is well, is that the oil drained from any of the 3 transmission components should  come out pretty much the same colour it went in. Perhaps a tint darker but not black unless that's the colour when it went in.

[tvrla]

It could have had some sort of Moly additive - my first thought. If there's no shiny bits or slivers on the magnet, then it must have been doing its job.

[Red_Hen]

Barry - I believe it was dirty from whatever residue was left in the reservoir from when I first got the bike - she sat outdoors for several punishing MN winters.  

I'll change all fluids at end of season.

FWIW, tranny gear oil is golden and that was disassembled and overhauled.

Checked  drive shaft oil but did not drain it.

[steven m]

If the FD was full of goo and the bike sat for a while you might consider changing the oil in the driveshaft, getting the bike nice and hot, and then draining and putting in fresh measured amounts into both.  Then at the end of the season it will be easy to tell if your driveshaft to FD gasket is shot by the amount of oil in each.  Do not overfill the driveshaft.

Just my two cents.

Steve

[Red_Hen]

sounds like a great suggestion - thanks, Steve.

Btw, I grew up in Beverlywood, adjacent to Culver City.

[steven m]

Beverlywood is my shortcut north.  Nice neighborhood.  Not fast but free of commercial traffic.

Filling the driveshaft with oil is tedious and if you use a funnel it will result in oil all over the floor.  At least that's been my experience.  I use a small old fashioned pump oil can, filled with a measured amount and squirt it in slowly.  A pipe cleaner is handy to wrap around the shaft and measure the oil level.

[Red_Hen]

I was thinking of turning the bike upside down and filling it thru the drain plug - hole is bigger >>>  

Actually, I have a syringe and fuel line for my U-Control model airplanes that I barely every fly anymore - I can measure the right amount of tranny fluid, put it in the syringe and inject it into the drive shaft hole.