terry Posted January 8, 2015 Share Posted January 8, 2015 As long as the rear u bolts are tight, the loose center bolt should not bother a thing, they only hold the pack together till the u bolts are torqued. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273556 Share on other sites More sharing options...
mackmb212 Posted January 9, 2015 Author Share Posted January 9, 2015 As long as the rear u bolts are tight, the loose center bolt should not bother a thing, they only hold the pack together till the u bolts are torqued.I was wondering if it would make a difference or not Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273651 Share on other sites More sharing options...
mrsmackpaul Posted January 9, 2015 Share Posted January 9, 2015 As long as the rear u bolts are tight, the loose center bolt should not bother a thing, they only hold the pack together till the u bolts are torqued.dunno about that I have only broken a center bolt twice and it pretty much becomes uncontrollable straight away like Im driving a yacht down the road I end real busy real quick on the steering wheel if it was mine I would fix it while its apart when I have broken a center bolt I have to pull up straight away and wrap some fencing wire or chain around the axle to the spring hanger just so it drives half reasonable Paul Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273661 Share on other sites More sharing options...
thomastractorsvc Posted January 9, 2015 Share Posted January 9, 2015 On the center bolt if you don't have the right tools i.e. torque multiplyer. large impact. ect.. wait til you are getting ready for paint and take it to a spring shop have them do both sides and in a few hours and a couple hundred it will be just like new. 1 Quote Robert"I reject your reality and substitute my own." Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273711 Share on other sites More sharing options...
mackmb212 Posted January 9, 2015 Author Share Posted January 9, 2015 On the center bolt if you don't have the right tools i.e. torque multiplyer. large impact. ect.. wait til you are getting ready for paint and take it to a spring shop have them do both sides and in a few hours and a couple hundred it will be just like new.I do for the most part have the tools or access to them it's just the condition of the other bolt that scares me. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273721 Share on other sites More sharing options...
terry Posted January 10, 2015 Share Posted January 10, 2015 dunno about that I have only broken a center bolt twice and it pretty much becomes uncontrollable straight away like Im driving a yacht down the road I end real busy real quick on the steering wheel if it was mine I would fix it while its apart when I have broken a center bolt I have to pull up straight away and wrap some fencing wire or chain around the axle to the spring hanger just so it drives half reasonable Paul [ /quote] My thought on this is 1200#+ torque on four U bolt nuts are going to supercede a 3/8 thick center bolt. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273813 Share on other sites More sharing options...
Vladislav Posted January 10, 2015 Share Posted January 10, 2015 The tranny box brake down seems repairable. Welding, soldering, brass soldering or just epoxy but well pre-cleaned and degreased.The generator mounting area doesn't look nice. Maybe to drill through and put studs instead of bolts? Quote Никогда не бывает слишком много грузовиков! leversole 11.2012 Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273818 Share on other sites More sharing options...
mackmb212 Posted January 11, 2015 Author Share Posted January 11, 2015 The tranny box brake down seems repairable. Welding, soldering, brass soldering or just epoxy but well pre-cleaned and degreased.The generator mounting area doesn't look nice. Maybe to drill through and put studs instead of bolts? that's what a friend of mine suggested about the generator mount holes , try to salvage what I can of the threads and soder studs in. If I come across a better engine for a good price will will get rid of this old 711. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273918 Share on other sites More sharing options...
Vladislav Posted January 11, 2015 Share Posted January 11, 2015 Don't forget any "new" part may bring "new" issues. Quote Никогда не бывает слишком много грузовиков! leversole 11.2012 Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273919 Share on other sites More sharing options...
mackmb212 Posted January 11, 2015 Author Share Posted January 11, 2015 Don't forget any "new" part may bring "new" issues.I know that's the scary part to trust the person saying this engine runs great and I buy then it blows up. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273922 Share on other sites More sharing options...
Maddog13407 Posted January 12, 2015 Share Posted January 12, 2015 I know a good spot for that turbo 711 rudy........ haha Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273969 Share on other sites More sharing options...
1957B61Vt Posted January 12, 2015 Share Posted January 12, 2015 RudyYouTube rudy?Was wondering if it wasSame truck . Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-273976 Share on other sites More sharing options...
mackmb212 Posted January 12, 2015 Author Share Posted January 12, 2015 RudyYouTube rudy?Was wondering if it wasSame truck .Oh no you guys figured me out, yes that's my truck and yes that's me dumping cans of ether into the turbo. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-274006 Share on other sites More sharing options...
DodgeMan Posted January 29, 2015 Share Posted January 29, 2015 As long as the rear u bolts are tight, the loose center bolt should not bother a thing, they only hold the pack together till the u bolts are torqued.I do agree with him on this. The center bolt was to hold everything together.. And to align the spring stack for assembly.... Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-276453 Share on other sites More sharing options...
hicrop10 Posted January 29, 2015 Share Posted January 29, 2015 The weight of my B87 is around 25,000 lbs.It has a triple frame,1200x24's tires,20,000 lb front axle,65,000 rears. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-276566 Share on other sites More sharing options...
DodgeMan Posted January 30, 2015 Share Posted January 30, 2015 yup, agree looks like a water push out. good welding shop can weld that right up with cast iron rod. I have seen a few Mack trans broke in this same spot actually. mine has about 15 pounds of brass on it. I ended up changing out the front case with a spare. glad to see you moving along on this gem and decided not to sell it.I agree!!!Best way to repair cast iron is to weld it with cast iron. (Best way)Stich and pin using lock and stich. (2nd best)A good v out and braze job. (3rd best)Nickel welding rods work but there's a 50/50 chance it will crack again then there really no way of fixing it after that it ruins the metal. And using a mig welder is a JOKE....My dad and I are going to drill and stich it for Rudy. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-276592 Share on other sites More sharing options...
mrsmackpaul Posted January 30, 2015 Share Posted January 30, 2015 I've 100% success with nickel rods so far dear as all get out to buy but they work well on any cast iron I've tried them onPaul 1 Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-276658 Share on other sites More sharing options...
mackmb212 Posted February 16, 2015 Author Share Posted February 16, 2015 The weight of my B87 is around 25,000 lbs.It has a triple frame,1200x24's tires,20,000 lb front axle,65,000 rears.thanks for the heads up on the weight. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-279339 Share on other sites More sharing options...
mackmb212 Posted May 19, 2015 Author Share Posted May 19, 2015 Well I haven't made too much progress on my truck but I'm back on the project. I got the drive shaft out and the trans out last night. I was working on the front axle back in the winter and discovered I need king pins and a deal fell through for a set of 22 in hubs.I am also trying to figure out what to do with the rear breaks, I would like to put modern cans on the truck and the smallest one's I can find are 24/24 chambers but there a little to big in diameter. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-290436 Share on other sites More sharing options...
Gmerrill0516 Posted May 19, 2015 Share Posted May 19, 2015 I have the same question on rear brakes but I assume if I go to the Mack dealer they can help me out. The ones on mine now are cobbled up DOT magnets...Welded yokes to the can rod...They need an offset slack adjuster or some such thing. If you figure it out let me know and I'll be sure to do the same...good luck Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-290441 Share on other sites More sharing options...
C609T Posted May 19, 2015 Share Posted May 19, 2015 I also own a b81 that I'm trying to install newer brake chambers on. Looking for a better solution to replace the old service cans Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-290467 Share on other sites More sharing options...
C609T Posted May 19, 2015 Share Posted May 19, 2015 I also own a b81 that I'm trying to install newer brake chambers on. Looking for a better solution to replace the old service cans Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-290468 Share on other sites More sharing options...
j hancock Posted May 19, 2015 Share Posted May 19, 2015 Page 63 has the dimensions for offset slacks that may help narrow down what you need.http://www.bendix.com/media/documents/BW1114QuickReferenceCatalog.pdf Quote JimIt doesn't cost anything to pay attention. Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-290481 Share on other sites More sharing options...
mackmb212 Posted May 20, 2015 Author Share Posted May 20, 2015 I also own a b81 that I'm trying to install newer brake chambers on. Looking for a better solution to replace the old service canshere is what I found today. Maxi chambers I have to find out the diameter yet though. I'm guessing these will give enough brake power and then a parking brake as well. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-290492 Share on other sites More sharing options...
C609T Posted May 20, 2015 Share Posted May 20, 2015 I've looked into these but found the studs not long enough to fit through the bracket with 65 rears. I don't think it's safe to take apart the chamber and install longer studs. Quote Link to comment https://www.bigmacktrucks.com/topic/38301-another-b81-build/page/2/#findComment-290507 Share on other sites More sharing options...
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