vn v8 overheating

[vn nut]

hey guys jus wandering if yas can figure out this one
got a reco,d radiator new water pump new thermostat
but yet my 5.0 overheats only in the first 5 to 10 mins of driving shoots right up to boiling point then comes down and stays down and sort of fluctuates but not much
no water in oil so dont think its my head gasket otherwise i dont think it would come back down ? bought another new thermostat the other day in case the other one was faulty n its not that
i was thinkin it might be a dodgy radiator after all it was a reco for 120 bucks any ideas guys
cheers

[Brin]

Hey buddy, same kinda story happened to me on the way home from work.

Had overheating problem - now new radiator, thermo, engine etc. Thought my overheating problem was gone. This engine sits maybe just under the second line whereas the old one sat dead cold. Sometimes this one sneaks to near halfway, but on Thursday arvo home the tamp guage was going mad, engine light on but car was running better than usually does so I didn't think much of it. Problem was though, at one intersection I was at boiling point (never seen temp so high) by the next section of lights, it cooled back down again.

Silly me crawled on m5 with an overheating car, got to mans house, opened overflow, then opened radiator slowly..... Silly me got very burnt with coolant. Had to hunt for radiator lid haha. Filled her up with water, bled it. Bled it again, put coolant in, and bled it again. Friday morn she creeped up halfway, it hasn't gone over the second line since

[Brin]

Put on the heater whilst bleeding it the second time - HUUUGGGE air bubble came out - makes sense - I been getting a swishy tap like noise behind steering wheel lately again. You got that??

[HARVZ-6]

should always have your heater on when you fill your cooling system from empty...

id bleed the system first up..

[Pub247]

car has to be at operating temp when thermosats is open to bleed system properly also have heater on full

[Brin]

Yeh I know.. Although the VN is tricky - the heater switch I mean.

I forget even now - When it's sticking out, it's on, or when its pushed back, it's on? I don't know.

All I know is I though I don't think the heaters on, bleeding her again, pushed the button and theeeeeeeere we go. Then the massive air bubble. Still think theres air in there though.

[vn nut]

thats probably the problem never knew you had to bleed a radiator how do you do this i just filled her up and off i went