School Bus Fleet Magazine Forums
Home | Profile | Register | Active Topics | Members | Search | FAQ
 All Forums
 Professional Garage
 Enter Forum: Professional Garage
 06 FS 65 coolant leaks
 New Topic  Reply to Topic
 Printer Friendly
Author Previous Topic Topic Next Topic  

Advanced Member

473 Posts

Posted - 12/30/2012 :  5:55:38 PM  Show Profile  Reply with Quote
Iíve got a 06 FS-65 w/C7 with 85k that is starting to become a cooling system nightmare. To make a long story short, in a 8 week span Iíve had four separate issues that have led to the replacement of the surge tank, several worn hoses, a water pump and both thermostats, and the surge tank cap and the bus is still not happy.

A few days after the water pump was replaced the bus started pushing itís coolant out of the overflow tube so I swapped the cap from a sister bus (didnít have a new cap on hand) and that appeared to stop the leak and the other bus hasnít had any issues yet. Itís been almost a month later and no complaints about leaks or loss of heat from the driver.

Today after shuffling the fleet around the lot to clean up all the snow, what do I find another leak! At idle the coolant is pushing itself out past the clamp @ the fitting where the lower step well heater hose passes through the firewall. Iím hoping itís a loose clamp, but itís probably not that simple. The hose felt rock hard and wasnít even that warm. At this point after idling for a while the water temp was at almost 200 but blowing cold, put the bus in gear and drive in a quick circle around the yard and the temp drops down to 175-180 and starts blowing great heat within a minuteís time. Didnít have the time today to dig any deeper, any ideas? Did I get a bad reman pump, do I have an air bubble somewhere in the system or a blockage, or is a new radiator in my future.

Brad Barker

861 Posts

Posted - 01/04/2013 :  5:02:12 PM  Show Profile  Visit Brad Barker's Homepage  Click to see Brad Barker's MSN Messenger address  Reply with Quote
Is there a booster pump on the unit? Was the coolant replaced during the work you did? This one is going to take some checking. Unless the coolant condition is really poor I would not suspect a radiator. If it is the same coolant from before have it tested. Cooling systems are probably one of the most neglected items. People assume they will run indefinatly with little problems when in fact they need regular schedule care and testing. Could be a air bubble, blockage, restriction, plumbed backwards or other. I am leaning towards plumbed backwards right now or booster pump running backwards.

Brad A. Barker
Go to Top of Page
  Previous Topic Topic Next Topic  
 New Topic  Reply to Topic
 Printer Friendly
Jump To:

School Bus Fleet Magazine Forums © 2017 School Bus Fleet Magazine Go To Top Of Page
This page was generated in 0.05 seconds. Snitz Forums 2000