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1998 Honda Civic Repair Question


Topics covered: Radiator, Coolant, Engine.
Mileage: 151,000 miles.

Asked on December 12, 2011

Losing coolant

Hi I brang my car to the shop and they pressure tested it and found no leaks under 15lbs of pressure and ran a leak down test and said everything is good. Today I drove about 25 miles and before I left my house the radiator was full on cold engine and after the 25instrument miles the Guage went up a little then went down and I opened the radiator and sure enough it was low again. It doesn't overheat and there no coolant in my oil and no oil in coolant and no white smoke. Where could my coolant be going? Im bringing it back to the shop again tomorrow. Ty
Avatar Asked by pmp

Answer

Replied on December 12, 2011

Are the floorboards wet? It HAS to be leaking somewhere. Tell them they need to test is to 17PSI with the engine at operating temperature.

Tiny Answered by rivermikerat (expert)
5,494 answers provided
Replied on December 12, 2011

The floorboard is dry ill check it again tonight

Tiny Response from pmp
65 questions asked
Replied on December 12, 2011

Ok. Let us know what you find out.

Tiny Answered by rivermikerat (expert)
5,494 answers provided

Replied on December 12, 2011

ok, the floorboard is totally dry. i even used a flashlight and checked everywhere underneth the dash for any drips and saw nothing. i waited till the car was warm and filled the radiator up again right to the top and stood there and watched it get lower and lower. earlier in the day when i did the 25 mile drive some coolant spilled out of the radiator because i had the car running and letting air bubbles out of the cooling system. i drove 25 miles home when i checked this. There was what looked like a leak on the bottom cornor of the radiator with a little coolant on the ground. Now im starting to wonder if its the radiator?

Tiny Response from pmp
65 questions asked
Replied on December 12, 2011

That's what it sounds like. The pressure test will tell for sure.

Tiny Answered by rivermikerat (expert)
5,494 answers provided
Replied on December 12, 2011

k the shop called me today its gonna be 270 and hes getting all the parts from honda.

Upper radiator hose.
some piece on the black that connects to the upper radiator hose. What is this piece called?
heater control valve
heater control valve hose

Tiny Response from pmp
65 questions asked

Replied on December 13, 2011

Upper radiator hose to block is most likely the thermostat housing. All of these items are things you can do yourself, and save a significant amount of money. The hoses and control valve are 2 clamps each; the valve is secured to the bulkhead by 2 bolts. The thermostat housing is secured to the engine by 2 bolts also. Remove those 2 bolts and pull the housing off the engine. Clean both sides with a wire brush or scraper, use gasket sealant on both sides, replace the thermostat, and reinstall the bolts. Make sure you pay attention to thermostat orientation. A $20 investment in a Haynes or Chiltons manual (from a store like Pep Boys, Advanced, or Autozone) will give you detailed instructions with pictures.

Tiny Answered by rivermikerat (expert)
5,494 answers provided
Replied on December 14, 2011

i got the car back today and everything is good except for one more problem now. The coolant is leaking from under the cap. i replaced the cap about 2 months ago from one from auto zone. When i put my ear next to the cap i hear a sizzling and air sound. How can the cap just start leaking? what do i do now

Tiny Response from pmp
65 questions asked
Replied on December 14, 2011

Let it cool. Remove it. And see if there is any grit or foreign objects on the radiator filler neck, or on or under the gasket on the cap. If these are all clean, check to see if the cap or filler neck is dented.

Tiny Answered by rivermikerat (expert)
5,494 answers provided
Replied on December 14, 2011

well it cant be dented its a plastic radiator. The cap looks the same as it did before. I drove it to advance auto earlier and opened the hood 5-10 mins later and i opened the cap and it had no pressure in it.

Tiny Response from pmp
65 questions asked