vn v6 s1 overheating

[Pimpn1]

hey guys, i have a s1 vn commodore, i have replaced the water pump, thermostat, waterinlet manifold gaskets, also the welch plug,
the vn will heat up to half way then the thermo fan kicks in, but the temp guage still rises, it got to just under the red mark tonight, its got oil, coolant, no milky under oil cap or dip stick etc etc, but it got really hot, the top hose was really hot couldnt hold my hand on it for long, but when i turn the car off it doesnt boil over and with it running i cant hear it boiling, so was just wondering what u guys think it could be as its got me stumped on the not boiling over part when it got that hot.
hope i made sence sorry if none of it does haha

 

[Pimpn1]

ok an update also, it will run half way when idling but when i go for a drive around the block it will rise up towards the red mark, but when i swittch car off still the same not boiling over, i put a thermometer on the top radiator hose and it was 38*C does this sound about right? this was straight after it went to red mark
cheers

 

[Nikkojoe]

Sounds like its a blocked radiator. Take it out and give it a quick flush through the outlets (reverse direction, bottom to top if you get what im saying) with a garden hose and see if any crap comes out of it. If stuff comes out, flush till the water comes clean, then put back in car and top up with fresh coolan and see if it works any better.

You can also take it to a radiator place and see if they can unblock the core, but I dont think a new entire radiator is all that expensive these days.

 

[Pimpn1]

hello so would this sorta explain the reason why it heats up while driving, cheers ill give it a try, if not then atleast thats eliminated from the list

 

[Nikkojoe]

Also, since you are running a series one setup, make sure the coolant is full as it can be deceiving. With the cap off, fill the bottle up with coolant and squeeze the bottom radaitor hose to remove any midle air locks. Its also best to run it with the cap off while filling the coolant bottle up.

 

[Pimpn1]

okies i just took the radiator out n found this, hahahahah so i degreased it and cleaned it thoroughly and put it back in, the car seemed to run ok at first when i drove it cooled down a bit, but then it started to rise again, i made sure it was topped up and was all good, now im leaning towards could it be a temp switch problem on the back of the motor? but still same the top hose got to 38*C and still not bubbled over as of yet

 

[social]

firstly, beleive it or not, coolant will actually keep your temperature lower than water will, secondly, by flushing the radiator, did you use high pressure? if not and just a hose, it wont neccessarily clean it thoroughly. Check your radiator pipes, they may have alot of gunk in them, if so replace / remove and clean them, a quick alrenative if you can, run the heater on with the windows down if the engine gets hot, it will lower the engine temp significantly you'd be suprised, remember when using the aircon, your making the car work harder than usual so higher temperature. If all else fails, yes replace the temp sender and see how you go. gdluck.

 

[Pimpn1]

i used my garden hose and flushed the radiator till it got cleaned and degreased the gunk on the outside to it can get a good airflow, i will have to buy coolant in the next couple of days as im only using water now since i took the radiator out, so im guessing the water would have made it reach 3/4 temp.

 

[Pimpn1]

i went out today and made sure the radiator was full, started it and let it idle for a bit, then took it around the block and all seems to be good, the thermo fan kicks in just over 1/4 so does that sound ok? also the temp only got to under half and didnt go any higher so hopefully the crap on the radiator is def all gone as it seems now, problem so simple and ended up being the last thing to look at haha cheers if anything else arises will update