mcratchet1

No i did not

Just had a question I have 07 mr688s cab over lately I’ll get no response to pedal for a split second while driving it always happens around 1300-1600 rpm’s it was maybe once a day now it’s most of the time. I check the batteries, connections, grounds, etc. awhile back I had no response to pedal at all so change the pedal sensor. It does not log any codes. I have checked EUP connections also. Any advice would be greatly appreciated 

Ok thanks for that input I know I have a few small leaks because next morning I only have about 40 lbs in tanks but just recently my purge valve is popping off every 20-30 seconds

Hey I have a 2007 mr688s the air compressor has started leaking oil getting a little out of purge valve. Should I change now or can it wait till the end of year ? Thanks 

Ok great thanks, just wanted to make sure!

I have a 2007 Mack mr688 the top carrier is leaking into bottom one over filling it. Is there a seal inside that separates them? Thanks!

Ok thanks guys I’ll try the oil and left hand bit and keep an eye on them! It’s a concrete boom pump on its back lol

Hey guys just was wanted a professional opinion I have 2007 Mack mr688s mp7 400hp

the #6 exhaust mainifold broke bolt the top one, is this the cause of another issue or just old rusted bolt? Should I try to get the one bolt replaced or wait to see if another one breaks? Thanks in advance!

No oil at all ever comes out of tanks at night I will check lines for build up thanks

I have 07 mr688s some morning it takes about 10 mins to build air most days only about 2 mins. I replaced governor check for air leaks and serviced dryer. Replaced filter and purge valve. I have had this truck 2 year I don’t when air compressor was changed. Is this a sign of my air compressor starting to fail?

No pto in front yes I’ll try that I’ll take the belts off and see thanks

I have 2006 Mack mr 688s with Horton clutch fan about two years old. It seems like every other day it will start humming almost whistle for a little bit then go away. Only while not engaged. All pulleys and belts are about six months old. Is this a early sign of clutch failure? Any advice would be really appreciated 

Ok thanks I check the hoses and tubing I don’t see any holes or leaks. It does not appear to be affecting anything just annoying. It seems to stay on only in the afternoon when it get hot

I have a 2007 mr688s with a 2-8 blink code which is combustion air temperature? Is it the boost pressure sensor that would cause this ? Thanks in advance

Just wondering if 75w90 is the right type of gear oil to be using in these diffs I work in northwest Florida 

2007 Mack mr688s 

Ok thanks, the hole was tapped to fit a heli coil I put one in last night but the bolt for tensioner does not seem to get real tight so I’m worried to death it going to come out. I did not know I could drill a hole bigger in tensioner that might be a great idea heli coil is a 10.5 but od is bigger of course the threaded insert sound better I will try to order some just was wondering if they will last or just do the dang cover thanks for your guys professional help I really appreciate it

Ok main belt was worn time to change grab tensioner was loose tried to tighten nope bolt pulled out with a heli coil around it sob! My question obviously owners before me fixed it with coil. Don’t know why it failed can I do the same or does some know a better repair ? It’s In the aluminum front cover tensioner #21291243 or is only right way to replace entire front cover thanks for any help 

Ok thanks for help guys, the scribe arrow was right. Thought that was strange but it worked. Installed, bleed air out and she steers perfect thanks again!!

The pump will not turn enough to align must be the big arrow

So turn it to that small arrow right

Ok that means I would have to turn heat pump 180 degrees to align is that ok

Reman gear has 2 marks but old one only had one and pitman arm only has one! It’s Sunday everything is closed would anyone know the answer please? Which make do I align 

Ok thanks for the information I think I’ll just get the reman and be done with it.

2007 Mack mr688s gearbox is leaking around shaft area. My question is how bad of a job would resealing it be? Instead of buying a reman for $1200

mack part# 8148592SV5R

or does anyone have a rebuild manual on gearbox any help would be greatly appreciated 

Hey guys I have to replace water pump this weekend just wondering if someone knew torque of bolts? It’s a 2007 mr688s 400 aset engine my first time changing this design. I have done several of the 2000,2001 models where pump sets in bracket. Any advice or heads up in would be greatly appreciated thanks!!!