Rep Power: 0

Hi, I bought my daughter a 2003 civic with 106,000 well maintained miles for her 1st car. It overheated on the highway because of a bad fan sensor and she drove it til it quit. Since then I've replaced the radiator+cap, thermostat, fan and ECT sensors, head+ head gasket kit, water pump, timing belt+tensioner +tune-up+oil change,engine +tranny flush.I think I covered everything according to what I've read on this great site but the reservoir bucket is still filling too much and overflowing thru it's plastic cap and it's not sucking back into the radiator. There are no codes. The engine coolant temp stays below halfway around town and we live in south Florida. She went on a three hour ride up Rt.95 last week and the temp went to hot as soon as she got off of the highway and into traffic because of coolant loss. The fans are working and they also work with the a/c which is always on. The oem thermostat is working also. It has a new aftermarket radiator and I'm wondering if that could be my problem.This has been dragging out a long time and I'd sure appreciate any advice. Thanks

 
Rep Power: 812

first check to see that lower rad hose is getting hot after driving. if not, thermo is stuck or rad is clogged.

 
Rep Power: 186

Or you could have cylinder pressure pressurizing the coolant and pressurizing your overflow because the head gasket is bad. And yes, I know you replaced it, but it doesn't mean it couldn't still go bad.

I would do a compression check on all four cylinders. Easy and quick to do. Hopefully you find they're all above 135 psi with no more than 28 psi of variation between cylinders.

Good luck.

 
Rep Power: 812

true, esp if she drove it til the engine died. more than a good chance the block was warped, or even the head, and when you put the new gasket it blew out right away. even with a new head, did you have it checked out at a machine shop before installing? and what about the block...

 
Rep Power: 0

thermostat is working so hose is hot. I'll do a compression test and check for clogged radiator today. thank you.

 
Rep Power: 0

the results of the compression test that I did today are 170, 160, 151, 170.Everything seems to be working fine when it's idleing..but,, The reservoir bottle starts out between the lines and after a 20 mile ride it is full and you can see anti-freeze on the fans and hoses because its pushing out of the plastic cap. Meanwhile the engine coolant temp guage stays below halfway. The coolant does not go back into the radiator on it's own. Also I'm using Prestone 50/50 anti-freeze. man,,,,I've been diy over 50 years and I never......thanks for all this advice, these hondas are strange.

 
Rep Power: 812

sounds like a small coolant leak in the head gasket.

 
Rep Power: 186

Agreed.

I know it's not what the OP wants to hear, I'm sure, but I would say it's a HG at this point based on symptoms thus far.

 
Rep Power: 0

Today the car failed the block test so I guess another headgasket is in order.

 
Rep Power: 812

this time make absolute sure the head AND block are not warped.