Hey guys, I drove home from work( about 25 miles) and stopped by the store. When I got out I noticed a puddle of coolant under my truck. I looked and it was dripping by the drain valve on the radiator. Id say a half a gallon or so on the ground. What was weird was there was wet spot on evaporater on top which was coolant. I didn't see any fins on the radiator wet at all. All the hoses were dry. Themostat and water pump was dry. I topped it off with water to get home and it drove ok. By the way my temp gauge doesn't work so not sure on that.. when I got home, no leaks anywhere but I noticed that the top of radiator, the cap and the lower rad hose weren't hot but the top rad hose was scorchin. Shut truck off, waited a min and then the top of rad was scorchin hot. Opened the cap and it was a lil low again. Topped it off again. Started up and top of rad was cool, top hose was hot. Shut it off and after a few, rad got hot again. Does it sound like my thermo isn't opening? Water pump not circulating?? My daily driver for work so I have to try and figure it out quick. Thanks for any help!

 

The lower radiator hose is the return so it will be cooler. Why is the temp gauge not working? Run it up to operating temp in your driveway and look for leaks. The radiator should be topped off. Do you have the reservoir hooked up? That should be filled up the the "full cold" line also.

 

The gauge quit working awhile ago, replaced the temp sender and now it reads high. I think the actual gauge is bad. Thats been a problem for months now. I understand the return line will be cooler but why would the radiator be cool as well while truck is on. Then scorching hot after its shut off? Seems like there is some circulation issue or something. I drove it home after the store and sat in my driveway with it on and didnt see any leaks anywhere. Really weird.

 

Is the radiator cool all over or just part of it?
If just part of it, you probably have a blockage where the water isn't circulating thru the whole core.

 

If it wasnt circulating properly would it build pressure in the radiator? Even if my t stat or pump was bad..it still leaked feom somewhere. Didnt know if it built up too much pressure and blew past the bottom drain valve on radiator

 

So long as the system is even reasonably well sealed, it will build pressure as the engine warms. If you have pressure immediately after starting a cold engine, you have bigger issues.

 

It would still build pressure.The radiator cap is release pressure at 16 lbs. or so. The only way to get too much pressure is for the cap to be bad.

 

Yeah ...if coolant disappears and it's not under the car (leak) ....and it's not in the oil ( which is worse ) ......then it is burning inside one or more of the cylinders (and misfires probably ) ...which is also bad .....but yeah - head gaskets and resurface of the heads is easy even for a DIY person ..... even set new valves while it's open - a set of 12 is like 80 bucks ....

 

9 Year old thread????? I would like to think this got dealt with some time ago...