I want to know how to change the primary gear oil in my 1999 s3?

The oil is most likely seeping into the engine and then into primary on your bike. This commonly know in this area as "oil sumping". It's quite common on the old Shovelheads and on Softails. The reason is that the oil tank is higher in the frame than the engine and gravity does it's thing over time. If the bike is allowed to sit up for an extended period of time, the oil will seep past the check ball in the oil pump and fill the crankcase with oil. Once the crankcase gets filled, the oil seeps into the primary through the Timken bearings on the left side of the engine.

If the primary is still in it's stock configuration, simply put a deep pan under the bike and start it up. It will pump a lot of oil out of the crankcase vent hose underneath the engine but it will eventually stop. Unless the primary has been converted to a "closed wet system" like an Evo has, the engine will pump the oil out of the primary as well. After a few minutes of running, shut the engine down and check the oil level. You can leave the oil dipstick out and watch to make sure oil is being pumped back into the tank. When it seems like all the oil has quit "puking" out of the engine, make sure the oil level is at least to the lower mark on the dipstick. Like I said, if the bike has been sitting up for a while, this is quite common.

Now, if he bike has been running and all the oil is being pumped into the engine but isn't being pumped back out, you may have a scavenge gear key sheared. This is unusual on a Shovelhead because they had metal breather gears in them. The Evo engines, on the other hand have plastic breather gears in them and they will break a tooth off the plastic gear, it'll go into the oil pump scavenge gears, shear a key, and the oil pump will quit pumping oil. If this is the case, you will not see any oil being pumped back into the oil tank. You can tell when it's being pumped back because the oil in the tank will be moving and it will be kinda foamy on top. This is because the oil is being pumped back to the tank. If the pump is not pumping the oil back to the tank, you must disassemble the oil pump or the cam chest and replace the sheared key.

Good Luck
Steve

I ride & have done my own repairs for years .current ride 09 flhtcu . I have had good luck w/ mobil1 for v twin 20-50 synthetic in motor . formula + harley or primary .. trany, spectra platinum for 6 speeds.. harley syn I personally do not like. in the engine,, you would not want to use syn in primary.. [Clutch] Ams if 20-50 should be OK in engine .. but trany is gears needs a GOOD gear oil...good ans. can be found on harleytalking.com ,, they have helped me..ride safe...

The thick oil has probably not harmed anything. It will make it harder to shift because it gets into the clutch pack and acts like a hydraulic fluid in a torque converter. I'm betting that now that you've changed the oil to Syn3 that it'll shift better. Just make sure you don't overfill the primary. With the bike standing straight up, remove the derby cover. The oil level should be no higher than the lowest point on the clutch spring. If you look at the clutch assembly, you'll see that there is an aluminum ring around the outside of the clutch with a darker colored disc in the center. The dark disc is the clutch spring. Fill the primary just up to the lowest point on the dark disc just over the bright ring.

If this does not improve the shifting into second gear, have the dealership adjust the shifter pawl adjustment. It takes some special tools to get to the adjustment.

Good Luck
Steve

Yes, there is oil in primary and transmission of your Sporty. To drain the oil, look for the drain plug on bottom of rear section of the primary area, back near the large round section of the primary. Drain the oil here and replace the plug. Add the oil at the top primary chain inspection port, large plug with a large "screwdriver" slot or two small bolts in it. Add 32-36 ounces of H-D "primary lubricant for Sportsters".

Pump is fairly simple...remove pan unbolt pump and reverse procedure. It is good to pre-lube pump and fill oil filter before starting engine. BUT: Keep in mind that a damaged pump is generally not the cause but the result of a failure elsewhere. Primary reason is rod or main bearing wear, resulting in debris scoring the pump gears and internal surfaces. Therefore, changing the pump will at best, slightly raise pressure only for a very short time. If after removing the pan, you find that the pump pickup is nearly blocked off by hard carbon deposits, you may have a chance of regaining pressure, providing bearings have not been damaged by low oil suppply caused by that restriction.

have you check the gearbox oil level / last gearbox oil service

You could get away with it for awhile, but I would only use oil formulated for the primary chain case, and for that part of the machine, I stick with Harley brand, dont forget , u got clutch plates in there u dont want slipping. For the tranny you wanna use a good grade gear oil (75W-90, 75W-110,75W-140, SAE 190 & SAE 250) .... it'll better handle the torque requirements. I use Redline Gear Oil and shifting has improved noticeably

Trans fluid and primary fluid are the same oil , The drain plug is under the laft side primary cover. 1 qt of oil goes in the inspection cover on the top side of the primary cover. The oil drain is a hose under the left side by the frame rail. Look for a oil line with a plug. fill with approx 3 qts through the oil tank. Make sure you get the bike up to operating temp before dropping the fluid.

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