Mower Gear Box Oil Level

[C.I.]

Picked up a 5ft BMB (B-5) mower. Probably built in the 80's. Very mild use. Has not run in 15+ years. Original owner purchased new. Had gearbox issue (from the start) and dealer replaced it within several years. First on the list is changing oil. This box has a large plug on the back side (not on top) at 12 o'clock maybe an inch from the top. It also has a allen type screw at about 4:30 toward the bottom of the box (below and right of the large plug).

Thoughts were the upper plug is the fill. The lower screw as the level line. No oil when top plug removed. To my suprise, there was 7+ paint can cap fulls which came out of the lower. Either that was not a fill line, it was just over filled or that is the plug to drain (but it's not at the 6 o'clock). If it is the fill line, its not half way up on the box. Question is where should I fill to?

The oil removed was dark blue and may never have been run (no blackness). This has sit so long the PTO does not slide. Any little tricks here or just WD40 the shaft and housing? Any comments appreciated..

Chet

 

[russb wa]

Chet, gear oil has one great advantage over motor oil. No combustion takes place. I don't recommend it but I go very far and long with out changing gear oil in a vehicle, transmission and differential. Some drain plugs are magnetic, which is good, clean well. I have had a Field General 5ft mower for going on twenty years and haven't touched the gear box. Probably has about 200 hours on it. Shoulda done it after break in and before break down. Wouldn't be a bad idea to do so now, thanks for reminding me. ;-)

As for WD40 it seems to have alcohol in the formula, seems to cause rust. WD stands for ~ Water Dispersant. You might be better of in the long run to use just about any other oil that is handy.

 

[souNdguy]

remove shaft.. set in a 5g bucket with some old diesel and other solvents in it.. like mineral spirits.. naptha.. etc.. maybee some used atf.. or a lil engine oil.
let it creep a few days...

once you get it apart.. wire wheel it and then regrease..

 

[L B]

Can you turn the gear box by hand? As long as it spins the blades and does not bind or grumble its a good sign. Is the oil seal on the gear box not leaking at the shaft and no oil leak on the under side of the box. I fill my JD as full as I can with 90W gear oil. I would say fill it like a rear end diff. on a car. You can set your telescoping shaft on end and spray it with PB Blaster and let it soak between the 2 shafts over night and tap the yoke with a hammer, repeat as needed till it seperates and grease the male shaft and work it back and forth. Make sure you have a SHEAR BOLT in it and NOT a graded bolt that is the most important thing on these mowers, it can cause lots of bad things if it does not break like it should. Before you start wait for a few more replys and you can see if I missed something.

 

[C.I.]

Thanks for your comments. First, I got the PTO housing and shafts to slide (slight tapping with hammer). In the process, I had to replace the wires holding the outer shield, nylon seal ring and steel ring to the shaft end. Just made my own. Seems to hold everything in place.

Smoothed shaft(straight edge razor blade with not much rust)greased shaft. Smoothed and greased inner/outer shaft housing (a bit more rust on the sheet metal housing than the shaft).

As for the mower, the PTO and blades turn with a simple light twist. Very smooth. It still has the original BMB decals along the side rails including the warning labels on the deck and PTO housing. I did find the mower side u-joint was missing its zerk. Must remove the u-joint cover to get that installed.

Will get under tomorrow and check the blades which should need sharpened. Almost have my 8N complete. Have taken her for a test spin and runs great. Just need to pull the tires, unbolt the centers, sandblast, repaint and install on new rims. I will need to replace the centers bolts. What grade is recommended?

Thanks again

Chet