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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: junkman42 on January 16, 2010, 05:46:22 AM

Title: cooling fan gear box mystery
Post by: junkman42 on January 16, 2010, 05:46:22 AM
After arriving home from bussin I checked the oil level in the cooling fan gear box.  No oil showing in the sight glass and no sign of oil anywhere.  Took about 20 ounces of oil to bring the level up to the lower third of the glass.  Where did the oil go?  Any idea's would be considered.  Hard to beleive that that much oil is invisible!  John
Title: Re: cooling fan gear box mystery
Post by: robertglines1 on January 16, 2010, 06:13:58 AM
make sure box vent is working...as to where??? slow leak and high velocity air....maybe
Title: Re: cooling fan gear box mystery
Post by: Nellie Wilson on January 16, 2010, 06:26:17 PM
MCI, I assume?

Any oil in the squirrel cage?  Maybe a bad seal where the shaft exits the gear housing?

Is it wet under the gear box mounting bracket? Even with drain holes, there might be some tell-tale residue.

Mine got pretty low (very bottom of the glass)  at one point but - like you - I never figured where it leaked (or even if it leaked).

Topped it off and seems to be holding fairly steady, though maybe losing a bit? Tough to tell unless you'e got a 'permanent' parking spot (even a little slope affects my reading).

Nellie Wilson
Title: Re: cooling fan gear box mystery
Post by: RickB on January 16, 2010, 06:47:23 PM
are you using 30 wt oil in it? There is usually evidence either on the saddle or on the ceiling of the cooling compartment or inside the scrolls. That's a mystery I agree most likely it's leaking onto the saddle assembly. I would pressure wash it, refill it with 30wt abd look for signs on the clean surfaces. Barring a crack in the housing it's only got a few places it can be going.

hope it helps

rick

Title: Re: cooling fan gear box mystery
Post by: Fredward on January 16, 2010, 07:12:21 PM
30 weight? My manuals are out in the shop but I could have sworn it takes 80-90.
?
Fred
Title: Re: cooling fan gear box mystery
Post by: RickB on January 16, 2010, 08:19:18 PM
When I rebuilt mine last winter the consensus I got from here, my manual and JD was straight 30 wt.

You could be right Fred but it would stink if you are because then I have to go drain the thing.

That 80 wt would sure help alot of leaky gearboxes.

Rick
Title: Re: cooling fan gear box mystery
Post by: Nellie Wilson on January 16, 2010, 09:47:39 PM
I was told 80/90 wt. Right or wrong, that's what I put in... seems to work fine.

Nellie Wilson
Title: Re: cooling fan gear box mystery
Post by: junkman42 on January 18, 2010, 07:55:21 AM
MC-7 and I have 40 WT Delo100 in the box.  If it leaked out I can not see it anywhere!  The amount I put in the box should be dripping off the ceiling.  Quite annoying for sure.  I wondered if it had anything to do with it being 28F outside but after it warmed up nothing seemed to change.  John
Title: Re: cooling fan gear box mystery
Post by: bevans6 on January 18, 2010, 08:52:57 AM
80/90 gear oil and 30 SAE engine oil have remarkably similar viscosities.  They are measured on different scales, since they are intended for different operating conditions.  Gear oil is modified with extreme pressure additives designed to allow the sliding action of hypoid gears as found in typical ring and pinion sets.  Non hypoid gears as found in the blower gear box don't need the extreme pressure capability of gear oil, but it doesn't hurt.  Normal SAE engine oil is equally good, as a rule, in such applications.

Brian
Title: Re: cooling fan gear box mystery
Post by: Nellie Wilson on January 18, 2010, 10:31:12 AM
Junkman -

Couldn't swear to this, but beginning to sound like it's going the same place those socks go. You know... the ones that disappear from your dryer?

Nellie

Title: Re: cooling fan gear box mystery
Post by: TomCat on January 18, 2010, 11:09:57 AM
Quote from: Nellie Wilson on January 18, 2010, 10:31:12 AM
Junkman -

Couldn't swear to this, but beginning to sound like it's going the same place those socks go. You know... the ones that disappear from your dryer?

Nellie



Hah! I finally figured out where those socks "go", and can now concentrate on the other mysterys of life!

Jay
87 SaftLiner
Title: Re: cooling fan gear box mystery
Post by: Hi yo silver on January 18, 2010, 05:55:50 PM
Yeah, those socks wind up in the "Hozone"!
Dennis
Title: Re: cooling fan gear box mystery
Post by: junkman42 on January 19, 2010, 08:26:09 AM
Nellie, thanks for the help!  So You have a dryer in Your bus that eats sock's?  John L.
Title: Re: cooling fan gear box mystery
Post by: Nellie Wilson on January 19, 2010, 08:35:32 AM
John L -

Only dryer in my bus is the air dryer...and it barely eats water. And below freezing, not at all. In the winter it serves as an ice-maker. ;D

Nellie