Overheating... why?! - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

SHINCHU · 09-08-2003, 02:07 PM

I was driving my s13 up the freeway and just happened to glance down at the temp guage out of habit, and to my shock and horror, it was about 3/4ths of the way overheated. (. ./.) about like that. i immediately pulled to the slow lane and limped home doing about 50. didnt get any worse but it didnt cool down much either. i wasnt going 90 or anything. just doing a casual cruise at about 70. didnt hear anything, no leaks, nothing. just pure HEAT. i got home and let it cool down and eventually checked my coolant level. looked fine. no oil in the coolant. nice and green. checked the oil. perfect honey colored and full. now i get curious and pull the thermo out. original nissan so i replace it. fire it up. overheats just sitting in front of my house in neutral with just 3,000 rpm of throttle and no load. i get even more curious and change my water pump. same thing.

could this be... the head gasket? god i hope not. i just put this engine in 6 months ago. this is a KA24DE, btw. its not under boost. no cams. just intake and exhaust and a couple drift events. regular oil changes and have maintained it like i work for NASA. has anyone else had wierd overheating problems like this? my next suspect is a clogged radiator. had that problem on my ae86. another wierd thing is the coolant seems to rise and fall rapidly in the radiator when i took the cap off while it was idling. almost like a pulse. wtf is it? any useful tips and knowledge are greatly appreciated. thanks.

09-08-2003, 02:07 PM	#1
SHINCHU Zilvia Member Join Date: Nov 2002 Location: Temecula, CA Age: 45 Posts: 244 Trader Rating: (0) Rides Gallery: SHINCHU Feedback Score: 0 reviews	Overheating... why?! I was driving my s13 up the freeway and just happened to glance down at the temp guage out of habit, and to my shock and horror, it was about 3/4ths of the way overheated. (. ./.) about like that. i immediately pulled to the slow lane and limped home doing about 50. didnt get any worse but it didnt cool down much either. i wasnt going 90 or anything. just doing a casual cruise at about 70. didnt hear anything, no leaks, nothing. just pure HEAT. i got home and let it cool down and eventually checked my coolant level. looked fine. no oil in the coolant. nice and green. checked the oil. perfect honey colored and full. now i get curious and pull the thermo out. original nissan so i replace it. fire it up. overheats just sitting in front of my house in neutral with just 3,000 rpm of throttle and no load. i get even more curious and change my water pump. same thing. could this be... the head gasket? god i hope not. i just put this engine in 6 months ago. this is a KA24DE, btw. its not under boost. no cams. just intake and exhaust and a couple drift events. regular oil changes and have maintained it like i work for NASA. has anyone else had wierd overheating problems like this? my next suspect is a clogged radiator. had that problem on my ae86. another wierd thing is the coolant seems to rise and fall rapidly in the radiator when i took the cap off while it was idling. almost like a pulse. wtf is it? any useful tips and knowledge are greatly appreciated. thanks.