Hey guys i have searched the forums and i haven't seen anything like this yet. Let me start off by saying that i have a D16Y8 in a 1998 honda civic ex auto tranny. So I live in texas and it gets really hot here and was planning on getting a bigger better radiator to put up with the heat. My stock radiator sprung a leak so I upgraded to a godspeed radiator and a Mishimoto transmission cooler. After installing this my stock hoses didnt fit just right and the lower radiator hose leaked a bit so i replaced them with Samco Sports hoses that fit better and while i was in there i replaced the thermostat with a Mishimoto 60 degree C thermostat. I noticed that my new hoses were getting radiator fluid on them and that my coolant overflow tank had a slow steady stream of fluid coming out the side of it making me put fluid in the radiator every time i drove somewhere to keep it topped off. This is where my confusion starts. I replaced my coolant overflow tank with a Weapon R coolant overflow tank and made sure that it was sealed so that no fluid could leak out of it. I even replaced my radiator cap with one from autozone just in case. I got to my friends house and with the a/c on it got warm so i turned off the a/c and it cooled down and i drove the 1 mile to my friends house and let it cool down then removed the new radiator cap and i had lost fluid. I replaced fluid and I drove to work checked my coolant and it looked like i hadn't lost any. After work I drove to my house (20 miles) and i had lost fluid AGAIN! I'm really confused but I made some observations over the last week or so. I loose about the same amount of fluid every time (just below the first radiator coil) and I turned my car on let it warm up and sat and watched my tail pipe for about 5 minutes and made sure that there wasn't any white smoke and i checked the oil and its not milky. Any help will be greatly appreciated guys! thanks!
coolant loss
- Thread starter Cobl18
- Start date
Today on the way to school it got hot again (i drive about 30 miles) after school ill check the coolant level. Do you think it could be a heater hose even though im not running my heater? I did a radiator flush last weekend and had to put in one of those splices on a heater hose to flush the system but there are no leakes from it. Any Help would be greatly appreciated! thanks!
Park the car on a flat surface and let it run for 30 mins, occasionally revving it and holding at cruising rpm. Look for leaks, you can use leak detector from any auto parts store to help see it, but at the amounts you're talking about it should be easy to see. Trace down the leak. I'd start with the thermostat housing, that gasket can be incorrectly installed easily. If you see no visible leaks and you still see loss, you probably blew the head gasket and are burning the coolant in the combustion chamber.
Thanks for your reply! I did what you told me and it was a mixture of 3 things. A small leak where my flush t was so i replaced it with reinforced silicon heater hose, a small leak on my thermostat housing so I put make a gasket on it, and a small leak on my new catch can so i mounted it better and replaced the hoses and routed it away from the hot transmission. I went on a 30 minute drive and came back home and what do you know my engine bay was as dry as a rock. Checked the fluid level an hour later and some fluid spewed out but I didnt loose any so I fixed it. Ill keep an eye on it the next few days but im pretty sure i fixed it. Thanks so much guys. 
I'm also going to add that i continued to loose coolant into my coolant overflow tank tank because i had it mounted to low in my engine bay and it had no problem putting coolant into it but it was mounted so low that my radiator couldn't pull in fluid when it needed it. I ended up flipping the mounting bracket upside down and mounting it like that. Now I'm not loosing any coolant and my radiator stays full. I wasn't sure if anyone else had this problem so i thought I would add it in here.