Anybody know the number of hours between oil changes in a 250 B&M Blower? I know you use 90 weight gear oil but how much and how do you go about changing the oil in the front and rear of the unit? Thanks
My 250 does not have gear lube in the rear just front. I'd change once a season. You should have a sight plug on the front of blower(face) You'll need to fill to the point lube starts to weep from sight plug.
Rebuilds mostly consist of replacing teflon rotor strips unless you have gear or bearing wear. As far as when you rebuild ?? I have no idea how long a supercharger will last between rebuilds. I'm not sure how accurate it would be to read your boost gauge. If boost starts to decrease @ WOT you may be losing some of your efficiency ?!
I think The Blower Shop is pretty reputable for rebuilds. I've heard their customer service is good too ! I'd give them a call. I think Marv is the guy to talk to. Some one will be able to post a number.
The rear is just beaings, no gears. I'm not sure if there's a drain plug. If I get some time today I'll go look to see if there's a lower drain plug. It would definitely be the easiest route and the cleanest. You may be able to just remove a bolt from the cover. I think it would get pretty messy by pulling snout. If all else fails loosen belt and remove the 4 bolts holding blower to intake. You can then remove blower and dump lube any way you want.
I just checked blower for drain plug. There's no drain plug. I have the installation instructions and for maintainence they say check sight/oil level hole for oil every 20-30 hrs. They have no mention of changing oil ?
Well maybe you don't change the oil and just check it. I would prefer to change it once a season anyway. As I acquired my blowers already on motors, i don't have installation manual. If I could bother you for a copy it certainly would be appreciated. If not, maybe I can get a copy from Holley. Thanks, John