I have determined that I have a leak in my cooling system as there is coolant all over under my radiator

However, I can't tell if it is a hose or the radiator itself.

I know a tool exists that you put on the radiator cap and pump air in the pressurize the system and spot the leak, but I can't figure out the name of it and can't find it online. Anyone know what its called?

Also, any other way to help spot a leak? It's a very slow leak.

Thanks

'98 Blazer LT

 

that would be a "cooling system pressure tester"
Craftsman Cooling System Pressure Tester - Tools - Mechanics & Auto Tools - Automotive Specialty Tools
check your clamps on the radiator hoses on both ends. the fan could be throwing it every where.

 

What I would do is let it run up to operating temp, and have someone rev it up a bit when you are looking around the area where you see the most coolant under your radiator.

 

DIY Homemade Cooling System Pressure Test Kit for about 6 dollars

Tools you will need are:
knife to cut hose and trim rubber gaskets, flat blade screwdriver, a 9/16" or adjustable wrench and a drill or reaming tool for creating the right size hole in the plastic cap.

Supplies needed:
Go to Wal-Mart and buy the Prestone Radiator Flush and Fill kit for about $4.00

Go to Napa for best price on a Metal Valve Stem with core that will bolt on for about $2.00

Cut heater hose and slide a clamp about 2-3 inches up on each hose. Then insert the correct size flush Tee in Heater Hose. Keep the cap part to the top. Slide the clamps towards the Tee and tighten clamps firmly.

Remove all hardware and gaskets from the new stem. Keep the bottom rubber gasket for later use.

Drill a hole through the plastic cap and rubber washer (at the same time) large enough to fit the Valve Stem. Check the fit from the top of the cap (outside). You want a loose but not sloppy fit.

Use an Exacto or any other sharp knife and trim the rubber gasket on the cap so that when you install the stem, the rubber doesn't squish out and cause a bulge under the cap.

Find the rubber gasket that was on the bottom of the stem and remove the small ridge of rubber from the gasket. Use that for your top gasket (outside) or any rubber washer that is flat.

Install the stem watching the gasket to prevent bunching up especially inside the cap.

Congratulations you have now built a cheap pressure test kit.

REMEMBER Never pump over 20 lbs of Pressure into the cooling system.

Use a bicycle tire pump or a small 12 Volt DC tire pump and pump up to about 15 lbs and a maximum of 20 lbs.

Look for coolant leaks and listen for air escaping the cooling system under pressure.

In the Alaska bush we may have to make many of our tools