A place for more technical discussions. Please make sure you post in the correct section on the site, this way it keeps the site tidy AND ensures you get a more relevant answer.
I was getting sick of the overheating issues showing on the car, so a month ago now, I decided to bypass the heater core as the gas tests on the coolant had shown no issues, but I still couldn't drive over 80KM/hr without the temp creeping up on the gauage even when fully bled.
Bypassing the heater core and looping the hoses together, I topped and bled the coolant once again, and I was driving around town with no sign of the temp gauge creeping up.
I even ventured onto the highway, showing the temp staying rock steady at the halfway point on the gauge. After 60 minutes of highway driving, the temps are staying steady. I did however notice that I had gained some coolant in the oiverflow tank. Let the car cooldown and the coolant then pulled back over to the radiator and all was good. I have driven around 900kms this way and only had to top the overflow bottle up with about 100mls of coolant at this point, with regular trips of around 20-40 minutes on the motorway now.
So it seems like I have a small head gasket blowout probably into the cylinders but its small enough that the loss amount is low. But wondering with the fact that I have bypassed the heater core mans I also had a leak in there?
Just getting the money and parts together to rip the head off and doing a head gasket, timing chain and valve seal refresh. The motor is at 358K km's now, and 200K kms since the last head gasket and rebuild it got, so makes sense it needs a little loving, but got me stumped why I couldn't find any exhaust gasses in the tests I had been doing, despite the system being pressurised enough to push to overflow.
