Basic question.
My GTV has never had an issue with overheating in the past, but in the last few days it has been running a bit warmer in traffic (admittedly weather has been fairly warm). Still mostly sits between 85-95'C, though normally it barely moves from the 80'C mark. The fan does seem to come on as normal.
However, when I stop and switch off, I seem to lose an awful lot of coolant from the expansion tank through the overflow hose. Its not leaking anywhere else, but I can hear water bubbling in expansion tank til it cools down.
Any obvious suggestions - blocked radiator maybe?
Forgot to add - have checked the oil and it seems fine, I can't see any obvious signs of water in it, so hopefully head gasket is okay.
Hi Poohbah
Check that the thermostat is working correctly, ie; remove and test in boiling water and see that it opens. If faulty, it's a cheap fix just need to replace thermostat and gasket.
bonno
Cheers Bonni, will check. Fingers crossed that's all it is.
Hey Poobah,
Maybe the fan sender. It's the sender in the top of the thermostat housing and they go as well.
If it's been warm and you've had the a/c on, the fan could be coming on for that but not for the radiator.
This is another "ask me how I know moment".
Cheers
Steve
Adelaide
Next time check if there is any pressure in the system
BE VERY VERY VERY VERY careful when doing this
if NO then you have an airleak generally near the cap the tank does crack with age
Thanks for those tips too guys. Will investigate all today. Having thought about a bit, I remember having a worn spring on the cap a while back, so tank didn't maintain pressure. But the cuurent cap is relatively new, so possibly there is an air leak in tank itself. It did look like some coolant was beading around the neck of the opening, but I assumed that was just spillage.
if it is a cracked tank what i did was drill the crack all the way like a windscreen to stop it going further
then all of the crack itself and then I used aryldite to seal it
seems to work well
they all break in the same spot
or get a new one around $100
Do a flush I used a heavy duty tectaloy flush cleaned all the cooling galleries solved my overheating problem also bleed the system might have a air pocket
Ignore what i said. I was thinking it was a 916 GTV.
Steve
Adelaide
Ha, no problem 490s. Thought it was unlikely - AC in my GTV has never worked!!
Starting to narrow things down. Tank seems completely fine, its actually fairly new, and no sign of cracking anywhere.
Is there a trick to removing the thermostat housing? Got the bolts out fine, but I couldn't budge the top half from the bottom of the housing itself. Its sealed tight.
Regardless, I ran the engine up to temp, and fan came on like clockwork just over 80C.
However, I also have a fan fitted to the front side of the radiator and it didn't come on at all. So I suspect that may be the culprit. Now to find out why its not coming on. It will be a pig if I have to remove the fan itself, its a bastard to get to.
I reckon you may be right that the front fan is for the AC, but I also think its aftermarket addition. Can't see any reference to it in Haynes manual. Most other Alfettas/GTVs I've seen with dual fans have had twin fans mounted side by side behind the radiator.
To be completely honest, I'm not sure if the front mounted fan has ever worked under my ownership. Since day one, when I've turned on the AC, nothing at all seems to happen (can't hear AC clutch engage) other than the blower in the console comes on
I'll go and give it a whirl now.
Poobah
Try tapping the thermostat housing using a piece of wood and hammer, just enough to break the seal.
Thanks Bonno, will give it a go on the weekend. Was a bit wary of not being able to put it back.
Doh - have also just realised another obvious likely contributing factor.
I had to top up the expansion tank twice over the last few days, but didn't have any coolant on hand. (I suspect the level was already on the low side before the first top up - I hadn't driven the car for a while, and forgot to check the coolant level before heading out for a longish run on a warm day).
So in the course of two top-ups I basically diluted the coolant significantly. Which obviously lowered the boiling point significantly...
Will now do as I should have done from the start, drain the system and replace with coolant. Will then be able to better gauge if there is still an issue.
As a matter of interest - what do you guys recommend as best coolant for the 2L?
I havent topped up for over a year
look further
hows the oil / oil cap
Oil and cap are both clean. No sign of water or coolant contamination in oil. Don't think I had topped up in over a year prior either.
Poohbah
Recommend and use on my Alfetta GTV4, Nulon Premium Long Life coolant 100% concentrate (Red).
bonno
Thanks Bonno, for this and all the other tips.
My pleasure Poohbah and hopefully the new coolant fixes the overheating problem.
I got the air con fan wired in series with the radiator fan so they both operate at the same time this helped a lot just make sure the air flow is sucking into the engine and not out..
Maybe you have a leak from the heater box is the carpet damp?? You shouldn't be loosing water
Carpet is dry. Only place I'm losing coolant is through the overflow pipe after i switch off following driving in traffic for a while.
Poohbah when I switch the beast off my electric fan goes on for around 3-5 mins
to cool it down maybe you should wire the fan up the same ie off the ignition switch
so it has power all the time and uses the thermostat to switch it on
this might stop the build up
also how full is the tank 1/2 way? or full
Cheers Carlo, that's a good idea.
Tank is now about 3/4 full (as per recommended markings), but its basically just water as I didn't have coolant on hand.
My plan this weekend is to drain cooling system, and replace with correct coolant, take her for a long run, and see if there is still a problem.
I'm trying to remember if my fan used to stay on after I switched off. I'm pretty sure it didn't.
Well, I hope I'm not putting the mockers on, but I'm going to tentatively call a success. Drained and changed coolant. Went for a decent run, got it up to temp for about 30mins, fan came on as it ought at about 85-90C, and when I switched off, no coolant overflow or unusual noises from the expansion tank.
Thanks all for your assistance.
Hi poohbah.
Hm, I doubt adding the coolant actually did the job. Water does a very good job at keeping a car cool but a terrible job of stopping rust and other stuff in your system. However, you may very well have had an air bubble or blockage in your system and flushing may have helped remedy that.
The front fan is not standard but since it is there I would either use it or discard it. As your A/C is not operational (and assuming you don't want it) you could wire it up to run in time with the engine fan. Perhaps also worth a check that it has been installed correctly with regards to direction of air flow (push or pull).
Given the terrible design of the wiring on those cars, I would suggest a new 5 pole relay mounted near the radiator. Power (30) from the terminal block on the DS inner fender; earth (85) from wherever is good nearby; the old fan wire becomes the feed to the relay (86) and the two outputs (87 and 87) go to the two fans. You get 12V at the fans (unlikely at the moment), preserve your ignition switch and wiring under the dash/fuse box), it is very easy to return to standard if you ever want to and you get two fans doing the job.
cheers Julian, it may well have been an air bubble that caused the initial trouble, given it's never had any similar problems before, but I'm still glad to have put the correct mix in car now. Took it for another run today and all went perfectly.
I've posted pics of the relays in my engine bay before - there are a mess of extras that a prior owner has added, but they still haven't addressed the issue of wipers and stereo dropping out when the indicators are on etc, even after I had the alternator rebuilt.
Probably needs a complete wiring overhaul to be honest.
Hi Poohbah
Good that you sorted out your overheating problem with your Alfetta GTV, by just flushing the system and replacing coolant. Just a tip that I just come across, that might be helpful to other forum members with an overheating problem and involves checking the correct operation of thermostat. This method allows it to be checked without pulling apart thermostat housing and checking it in boiling water. It uses the squeeze method of the radiator hose once engine is hot refer Method # 3 (difficulty in removing thermostat housing in an earlier thread) . Refer to the following link for details :
http://www.wikihow.com/Tell-if-Your-Car%27s-Thermostat-Is-Stuck-Closed
bonno
cheers bonno, handy tip.
Well - whatever the cause, the act of replacing the coolant seems to have fixed it. Did a 280km round trip today including 40min each way in peak hour freeway traffic, plus high speed open road, and 15min in CBD traffic, and didn't shift off 80C.
aahh the italian tune up
never discount the effects of a good run