Torque spec, B&M 250???

[Craig]

Anyone recall the torque spec for the four hold down bolts on a B&M 250 blower. I know it's not much, I though I recalled it was in inch pounds. Much more and it seems to twist the case and bind the rotors.
Craig

[acatitude]

Craig, I dont know exactly but I have a 420 b/m and I torqued mine to only about 12 lbs. There are some sights that give #'s, just be sure your blower will spin freely. If you cant find them, I have my instructions in garage somewhere I can look at.

[HM]

Craig:
Anyone recall the torque spec for the four hold down bolts on a B&M 250 blower. I know it's not much, I though I recalled it was in inch pounds. Much more and it seems to twist the case and bind the rotors.
CraigI have a B&M 250, and the spec called for 12 - 15 lbs. I also have mine at 12 lbs. At 15 lbs, you can feel the rotors start to bind.

[Hustler]

Dont forget to torque from the inside out and do both sides at the same time.

[pleasantcat]

craig here we go from the book
tighten the four bolts finger tight. tighten the bolts in sequence to 12-15ft-lb in two or more steps.check to see that the supercharger does not bind when its turned.(see figure 7 in general instructions) step 7
use thread sealer on all bolts.tighten the bolts finger tight. in gradual steps, with a torque wrench,tighten these bolts to 5ft-lb then to 10ft-lb. as you tighten the bolts turn the inputshaft of the blower. on 250 blowers continue to 20 ft-lb.
i hope this helps.... btw blownvee needs to get a safer set-up.... all this h.p. and no ext. rams eek! do you or donnie have a 30p i can barrow????? let me know..sean

[Craig]

Thanks guys, we'll torque that boy down tonight and put the right length belt on the blower, see what happens.
Plesantcat, yeah I keep tellin' the boy he needs to go back to a cat. He'll either kill himself or blow that motor up eek! Donnie has two 30 pitch props. I think I sent you a pic of his recently "modified" one. I'm sure he'll let ya' try that one out? You going out this weekend? We're thinking about going out Saturday.
Craif
[ August 06, 2002, 04:16 PM: Message edited by: Craig ]

[pleasantcat]

sounds like saturday it is.... i dont think i'll be able to spin that prop... to much cup have fun tonight...sean