12R running temperature..TOO HOT?

[StuRT104]

Howdi all i just picked up my RT81 today and i think its running a bit hot. I flushed the radiator n replaced the thermostat. Radiator seems alright, no damage around the head gasket,hoses are all in good condition no leaks anywhere. The temperature guage says its running on 3/4's is this normal for an automatic 12R?

Cheers

[woggin]

run it without the thermostat, if it runs cooler, there is sumthin wrong wit ur cooling system, id say blocked rad core!!

[sbfoot]

might be a good idea to get the radiator professionally cleaned and checked,shouldn't cost too much unless he finds something wrong.its also a good idea to invest in an inline cooling system filter as these old cast iron blocks tend to fill up with crud and can block your core,not good if you've just paid money to have it cleaned.
good luck.Scott

[MWP]

The temperature guage says ...
Cheers

There is your first problem.
Dash temp gauges should never be trusted!

[StuRT104]

I think the temp guage is correct because it does spill out of the overflow

[StuRT104]

Just let the car idle in the driveway for a while and the temp guage said it was at 3/4, radiator hoses didnt feel too hot(not even close to expanding) and the exhaust fumes werent even that hot. Are 12R's easy to change heads on? If so i may replace the head gasket as the car has done 230,000kms

[sbfoot]

very easy to take the head off a pushrod motor,just do it when the engine is cold to reduce the chance of warping the head when removing it.(should be alright being cast iron)
Scott

[StuRT104]

so ya reckon the head gasket may of split on the inside near the cylinders so thats where all the heat would be coming from? i just did the head on a 18R and that was a prick of a thing because of the auxilary shaft and 2 timing chains, still havent worked out whereabouts the oil bolts go for it lol

[StuRT104]

Well i have come to the end of the road with the RT81. I have:

Had Radiator reconditioned
Replaced all cooling and heater hoses
Got head shaved and welsh plugs repaired
Fitted new head gasket
New thermostat and thermostat gasket
New radiator cap
New water pump and gasket
Running Tectaloy coolant in it

Guage is still reading 3/4 however it does not move, so i think out of all of this it is the guage a lot of work and a lot of money but at least now i know that it is not overheating, any other ideas?

[CELICASUPRA7M]

seing as how the cars basically got a brand new cooling system.... it will prob a gauge prob.
best thing to do is fit a after market gauge to the car.
i got a speco elec one for $50 plus a fitting to plum it in the top hose $15. then you will know exactly whats going on. you can actually see the thermostat opening on the guage.
good luck

[StuRT104]

have you got a pic of how you plummed it into the line? I bought a aftermarket guage but couldnt replace the old one with it because the sensor bullet thing is too long to fit in the head hole if that makes any sense to ya

[CELICASUPRA7M]

yeah that makes sense! i'm imagining your gauge to have an thick (4mm) flexable line running to the 'bullet" sender??
if so this is a mechanical setup not electric. dont no what brand yours is but with a speco you can buy an aluminium fitting with the right thread to screw in the sender.
you simply cut about 30mm out of the top hose and clamp this fitting inline. then run the flex line through firewall to the gauge. dont know how to put pics up but if you go to the speco site you can see what i'm talking about.
good luck

[MWP]

There is your first problem.
Dash temp gauges should never be trusted!