My initial interest in this was because I bought a spec B, h6 auto with 183xxxkm and noticed the temp gauge going way up on long hills. Engine oil looked perfect, no real sign of a head gasket but I did notice a gurgling sound in the dash so was worried about a clogged heater core, air lock and/or head gasket. Plus I was loosing some coolant out the overflow bottle.
About 2 weeks ago I ordered a pair of 5/8 x 1/2inch brass tees (
https://www.ebay.com.au/itm/333433867586 ), drained the coolant, checked the flow through the heater core with the garden hose (definitely no blockages there!), installed the tees and 1/2" bypass hose before the heater core, drilled a 3mm hole at the top of the thermostat beside the jiggle pin thing and everything has been sweet since.
To bleed the coolant I:
- Jacked up the front as high as possible.
- Took the top hose off the throttle body (this looks like the highest point in the system) and waited until coolant came out of that (while filling the radiator) before reconnecting.
- Then did the usual jam a funnel in the radiator, run until it gets hot, squeezing top and bottom hoses etc. which took about 20-30min i think.
Since then I haven't had any issues, the temp gauge does move very slightly but no where near like it did before and so far I have not lost any coolant from the overflow bottle. Also the heater works fine.
Does anyone else's temp gauge (EZ30's) move at all when driving?
Also note: I think the car was serviced just before I bought it, the coolant looked VERY clean and the thermstat looked brand new. Fair chance the mechanic didnt bleed it properly in the first place.