1999 Ford Ranger Coolant

1999 FORD RANGER
90,000 MILES • 6 CYL • 4WD • AUTOMATIC
Avatar
AGILEMUTS
  • MEMBER
  • 1 POST
The coolant in my Ranger flows into the coolant reservoir when it warms up and won't flow back when it cools. I put on a new radiator cap, new thermostat, had the system flushed out and pressure checked, they said it was good. If I don't drain and put it back in the radiator it will blow the lid off the reservior spill coolant everywhere. Any ideas?
Jan 28, 2010 at 7:37 PM
Advertisement
Avatar
MHPAUTOS
  • ✓ASE Certified Mechanic
  • 31,937 POSTS
  • ASE Certified Mechanic
Hi there,

This is normally a faulty pressure cap, as the coolant warms and expands excess coolant flows into the header tank, as the system cools and a partial vacuum forms in the block, coolant is forced back into the engine by atmospheric pressure acting on the head of coolant in the header tank, you will either have a faulty cap or a leak in the system somewhere.

Mark (mhpautos)
Jan 28, 2010 at 7:42 PM
Avatar
TOOOMANYTOYS
  • ✓ASE Certified Mechanic
  • 513 POSTS
  • ASE Certified Mechanic
Have you tried replacing the hose from the coolant tank to the radiator. If it has internal blockage the pressure will blow through, but the vacuum may not be strong enough to pull it out. If that doesnt work I would suggest doing a block check to make sure there are no internal engine leaks.
Jan 28, 2010 at 7:47 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.