Hi there bloke. My heater core was badly blocked so I pulled it out, filled it up with strait rad cleaner and let it sit for a day. Didn't make any difference. Was still full of junk and it was there to stay so got a second hand one from the wreckers for 88 bucks.
I did put the old one back in before I got the new one then I run liquid intelligence through my cooling system because my block was that full of crap I seized the motor twice within 1000kms.
Factor temp gauge never moved on both occasions. The liquid intelligence must of done its job because I ended up with a hole in the heater core forcing me to get another one.
Engine runs cooler than it ever has before.
I think if yours is as bad as mine was you best getting another one. Be rite for yrs.
mine was so blocked it would blow warm air for about ten seconds when turning on the fan then it just went cold.
Keeping my cooling system in good condition is my no1 priority now.
Is nice having a heater again also.
Hey mate cheers 4 that but after it sitting 4 a while and then I thought I'll disconnect the hot cold lever and played with the adjustment then gave the lever a good few rips then put air in reverse BANG out it came with all the alcoline all over me and the paint, just took it 4 a drive and got up it to try overheating it and won't go past have half on the gauge