I have a MC 8 1975 the radiator blower gear box was low on oil. What oil does it take? Gear oil or tranny fluid or ????? Thanks. Revbusnut
The service book for a 79 5C calls for SAE 30 motor oil. Clarke did an informative post on this and it seems they reccomended 30 wt becuse it is eaisely available! So I use SAE 40, becuse I carry it with me!!!!
Work?/Play safely Jim
I run straight 40w in my 96A3.
Hi there Revbusnut,
How did you realize the radiator blower gear box was low on oil? I'm just showing my ignorance here. It sounds like something I should be checking.
Best Regards, Phil
Phil,
There's supposed to be a level check sight glass window on the box, next to the belt pulley. Here's a couple photos. The sight glass is the tube on the left in the first photo.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.gumpydog.com%2Fbus%2FMC9_WIP%2FMechanical%2FRadiators_And_Blowers%2F010827.06.blower_drive.JPG&hash=c4180a369a4d6f413a3e1e81fa8d1b1e0e84a168)
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.gumpydog.com%2Fbus%2FMC9_WIP%2FMechanical%2FRadiators_And_Blowers%2F010930.08.drive_oil_level_full.JPG&hash=d5b6e0ef2476cfcaedcdc73309121f2de8d1d986)
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.gumpydog.com%2Fbus%2FMC9_WIP%2FMechanical%2FRadiators_And_Blowers%2F020611.01.blower_drive_and_fans_installed.JPG&hash=33a51b0ff38b83af0cc3a78cb862f13d233d6079)
Craig - I learn so much from your posts!
Thank you for the great explanation and pictures. That is my mission tonight - checking that out, learning something new. It may save me some $$$ too.
Then - back to my new "under the counter tree limb lights" ;D
Best Regards, Phil
Craig I too would like to thank you for your most informative site. More than a few times I have used it for reference. On my shop table(after much cleaning) are the blowers. Hope they turn out as good as the ones above
Danny
Spiffy Radiater compartment there gumpy!
oops, there goes the Bus envy :D
8)
FWIW.......
My MC5A has a Spicer crash box and the book sez use 40# oil...the same as the engine. I don't have any idea how long it's been sinece it was changed but when I recently pulled the engine I asked my mechanic to drain the Tranny and replace the oil with 50#
Racing oil. I'm a happy camper. I feel I'm taking advantage of the better lubricity of the weight and the composition of the oil and I'm not "Crashing" the gears as I once was.
Now, to the blower drive. I know mine needs resealing but I'm up to my ears in alligators right now so it's going to have to wait until this winter when I get to FL. I'm going to try the same reasoning and drain and refill it with the 50# Racing oil. What have I got to lose?
I will report back if it lessens the leaking but after resealing it I will still use the 50# oil. ;)
Bob
Gump, very nice looking blowers! Are those the "large capacity" blowers? I've never seen blowers that go thru the blower box floor? Remotely remember reading something about them.
Are the blowers OEM in your coach or did you retrofit them? I'll have to go back to your website...I remember you describing the rebuilding of the units.
I run 40 weight in my gearbox...same as the engine. I've got a RH seal seeping. Only added oil once in 5 years.
BTW Gump, you better check your water level...you got some hoses that fell off! ;)
JR
Yeah, those are the original blowers. I think the smaller ones were mostly on the older MC8s. Not sure if they were on any early 9s.
I put a smaller diameter pulley on and new cones. The housings on the blowers are new, also, as my old ones were pretty corroded.
The compartment looked nice when the photos were taken. It's not so nice now, after several thousand miles with lots of rain, dust, snow and salt. I should have sprayed the pipes after I shined them up. They've all turned green now. I'm planning to replace all the rubber hoses soon, and may go through the shine process again, and this time will clearcoat them.
craig
Hmm. Craig must be mistaken - I'm looking at my blowers - no site guage.
Oh well.
....
What is that greasy blob? Let's clean it up... Hey - a site guage.. And it's empty.. >:(
Craig was right - again. :D
Using straight 40# oil. Filling it up. Looks a bit dirty - guess I have to drain & re-fill?
Another problem averted thanks to fellow busnuts on the MAK board. Awesome.
Thank you Craig, Brian, Jim and other contributers to this thread.
Kind Regards, Phil
Hi Phil,
Craig's always right!
Regarding your blower gearbox, you may want to remove the belt and check the "feel" of the gears and bearings in your gear box. To easily remove the belt, air up the bus and turn the knob next to the belt tensioning cylinder and the cylinder will retract....allowing the belt to almost fall off. Then you can feel what you have. You don't want to have the box fail out in Lower BF...that would be a show-stopper for sure. If it still feels smooth, probably OK. Where did the oil go? You probably have a side shaft seal leaking. Check for play in the blower and pully shaft too. May find why it's leaking...?
If it's actually dry...it may overfilled and you cannot see the oil level line.....you may have damage inside the gearbox.
Nope....just saw the clean pix...it's very low! :o
JR
Hi JR,
Thanks for additional troubleshooting help. I may actually know what I am doing some day. HaHa!!
I will indeed try the "feel" test via belt removal.
It didn't seem like the gearbox was dry. I would approximate that it took about 1/4 quart to bring up the site guage to the 1/2 site level. Unless of course, that was what it take to bring it from empty to full :-\ I don't know the gearbox capacity. I can check my manual tomorrow for this.
Kind Regards, Phil
I don't recall for sure, but it seems like it took more than a quart to fill from empty. If yours only took a 1/4 of a quart, you should be fine. Obviously, there's a small leak somewhere, probably shaft seals. That's why there's oil and grime all over the sight glass and under the gearbox.
Now you know how to check it. You should be opening up that compartment before starting every time, anyway, to check the water level, so keeping the blower gearbox sight glass clear will be one more thing to do.
BTW, nice photo on your initial search for the sight glass. If you hadn't been told there was a sight glass there somewhere, you'd have never known. It looked just like the head of a bolt or plug. That's how many older bus sight glasses are, and the reason many owners don't know how to check the level of the oil in the gearbox. If there are no leaks, the owner/mechanic gets out of the habit of checking (because it's uneventful). Unfortunately, when a leak develops, it's not obvious because the sight glass is crusted over with grime. Don't let yourself get into the habit of ignoring it.
Oh, and JR, Craig's not ALWAYS right, and he'll be the first one to tell you so.
;)
Hi all,
I wish that we could put sound bites in here.
Mine would be of feet running out the door every time I read a post that points out another way to check on the ol' bus.
Thanks for the heads up!!!
Devin
by the way, what is the gauge that is mounted to the remote control box. Mine is pretty busted up.
Devin, Its a mechanical water temp gauge. I added a mech engine oil pressure gauge beside it also. The main thing that these do is gives you a system of checking the accuracy of the dash "electrical" gauges........of course,the logic is that the mech gauge is more accurate. HTH chuck
90wt gear oil. DO NOT OVER FILL IT WILL BLOW OIL TO KINGOM COME!