Overheating/coolant boil over only after 25mi highway drive
05-25-2016
#1
Registered!!
Thread Starter
Join Date: May 2016
Age: 44
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 
Overheating/coolant boil over only after 25mi highway drive
Hello,
Experiencing an issue on the highway where temp needle will go up. I pull over and see that my overflow tank is boiling and shaking. Radiator has loss of fluid and need to fill with water. Once this started, it will do this about every 25-30 miles...but only on the highway. When I take short in town trips, say 10-15 miles, let the car cool, I see that my radiator is full and overflow level is where it should be (doesn't appear to have any coolant loss during short trips, plus I see no leakage on garage floor). Made a number of these in town trips with the same results. Changed the radiator cap and went out on the highway to test but had boil over after 29 miles.
Car has 335k on it and I replaced the head gasket at 270k (head prof. Machined). And has run for 3 years and 65k miles without any issue up until now. Many of those miles being long highway trips.
These are different symptoms that I had prior to HG replacement which I could drive on highway for long 80 mile trips and simply had to transfer full overflow tank back into radiator and could go for another 80 miles...so I'm just not ready to scream head gasket yet. This time it's like as long as I don't leave town, I wouldn't see any overheating issues.
Any ideas? Thanks in advance
Experiencing an issue on the highway where temp needle will go up. I pull over and see that my overflow tank is boiling and shaking. Radiator has loss of fluid and need to fill with water. Once this started, it will do this about every 25-30 miles...but only on the highway. When I take short in town trips, say 10-15 miles, let the car cool, I see that my radiator is full and overflow level is where it should be (doesn't appear to have any coolant loss during short trips, plus I see no leakage on garage floor). Made a number of these in town trips with the same results. Changed the radiator cap and went out on the highway to test but had boil over after 29 miles.
Car has 335k on it and I replaced the head gasket at 270k (head prof. Machined). And has run for 3 years and 65k miles without any issue up until now. Many of those miles being long highway trips.
These are different symptoms that I had prior to HG replacement which I could drive on highway for long 80 mile trips and simply had to transfer full overflow tank back into radiator and could go for another 80 miles...so I'm just not ready to scream head gasket yet. This time it's like as long as I don't leave town, I wouldn't see any overheating issues.
Any ideas? Thanks in advance
05-25-2016
#5
If you think a good mechanic is expensive, try hiring a bad one
Re: Overheating/coolant boil over only after 25mi highway drive
How old is the radiator? Thermostat?
Cooling efficiency compromised by lime/calcium inside, or leaves/bugs/sand/dirt in the fins of the condensor and radiator?
Cooling efficiency compromised by lime/calcium inside, or leaves/bugs/sand/dirt in the fins of the condensor and radiator?
05-25-2016
#6
Thread
Thread Starter
Honda Civic Forum
Replies
Last Post
btungcab87
Mechanical Problems/Vehicle Issues and Fix-it Forum
16
12-04-2015 10:20 PM
steve6
Mechanical Problems/Vehicle Issues and Fix-it Forum
5
11-22-2015 08:18 PM
