Finally Got the charger out n fired up the blazer

[slyguy_22]

Well i finally go motivated to get the charger out and charge the bat on the blazer and get it preped for spring. fired up just fine and let it warm up and then i notice the puddle of oil Im suspecting that it is from the rear main seal. Im gona clean it off and double check if its not too cold this weekend. its a 406 sbc. ive read that alot of people replace the the rear bearing. I would think you'd wana replace all the bearings? Can this be done with it in the truck? what about the top bearings will they slide out? last time i replaced bearings it was a 350 block on my engine stand never tried to do it with the motor in the truck. Any suggestions or input would be helpfull!

 

[apache]

Thats a new one on me but im no expert on 406 SB`s. If one bearing is gone Id think the rest of them along with what else is spent more than likely. Without backing off all the bearing caps and making some play between the crank and journal I cant see that going well or worth the hassles or probable bad results.

 

[toomany]

You don't have to replace the bearing when doing the rear main seal. Plus I think it would be a bad idea to replace just one. Crank bearings wear with each other. Putting one in that is thicker than the others wouldn't be good.

The seal can be replaced while the motor/trans is still in the truck. It is easier if the trans is removed and the flywheel/flexplate can be removed. The seal may be difficult to get out if it's been in there awhile.

 

[slyguy_22]

Yeah i thought that was kinda weird too about the bearing. Ive decide to build my 72 so im gona use the 406 in that anyhow so im gona be yankin it anyhow. gona give it some move beef and ditch the tbi and swap cams. the block only has bout 5500K on it anyhow, im sure the only reason the seal went out is cause it was sitting for bout 3 months and i fired it up when it was super cold out.