overheating GTV

[Beatle]

Heading for 44 deg C today in Perth......

[poohbah]

+42C the last three days in a row at my place. I have walked out to start on it twice and turned around and came straight back in to the AC again.

And all of a sudden the GTA, in black on black, is not sucha cool place to be...

[poohbah]

I've hit a bit of an obstacle.

Managed to remove the thermostat, which required some persuasion as it was sealed tight with sealant.

Popped it into a pot and brought it to a boil and basically nothing happened that I could see. So it would seem that it is buggered.

Unfortunately, the replacement thermostat I bought from Repco (a Dayco item that I was told was suitable) will not fit as the one in the car appears to be OEM, and therefore a combined housing/thermostat unit (pictured).

The only other apparently suitable alternative that Repco, Autobarn and Supercheap could identify is a Tridon model that is pretty much the same as the Dayco, and is meant to slot into the existing housing. They are an entirely different size, shape and 'style' to the OEM one which has a central locating pin extending from the top that sits in a collar in the housing.

I was able to remove the OEM thermostat from the housing by pushing down on the spring and rotating the centre clip, but that's not much use if I can't find a replacement.

So for the moment I'm stuffed - will try my Alfa workshop in the week to see if I can source an  OEM or NOS part.

Unless anyone else has any suggestions?

[poohbah]

Cheers Sportiva,

I was going to ask whether I could just drive it without one til I find a replacement. Might also provide extra proof of whether it was the thermostat that was the issue.

I'd prefer OEM if I can find one, don't fancy hacking out the retainer posts.

I recall reading somewhere that someone instead swapped it for a 105 housing, and that fits normal Tridon or Dayco thermostats?

That would present pretty much the same problem though - I'd have to find a 105 housing first.

Searching online, looks like I can get a genuine replacement for about $120. But I'll try the alfa workshop first.

[poohbah]

yep, already removed the thermostat from the housing. Which is very easy by simply pushing down and twisting the retaining clip - and totally at odds with Haines which advises to never try and separate the two as '"the components cannot be separated..."

[Craig_m67]

Soooo.. whack the housing back on and take her(?) for a decent fang!


(Italian tune-up, mileage and results may vary, never mix on a double demerit point weekend)

[poohbah]

So, I have now managed to buy an OEM thermostat (ie the full assembly in it its housing) - no local parts stores had them and the local Alfa workshop (Cileberti Motors) I go to was closed last week for the NY break.

Went back to the workshop on my lunchbreak and walked out with the requisite part in 10 mins.  Part cost $108, but that is about $50 cheaper than getting the same part online (including the postage).

All going to plan, I'll get time to fit it on the weekend.

[poohbah]

Update.

So I finally managed install the new thermostat. What should have been quite a simple job ended up a right PITA.

First, when removing the old housing, the inboard retaining bolt came out with the socket - which I didn't realise til hearing a double ping of it bouncing off something. Spent at least half an hour trying to find it without any luck (no idea, not on the ground, nowhere in the engine bay i could see). Bloody witchcraft. It simply dematerialised.

Regardless, it would have been worthless anyway. As it turns out, the thread in the bottom half of the housing must have been either partly stripped or worn down, because neither the matching bolt from the other side nor a new matching size bolt would screw tight - about 2/3 of the way in it would just start rotating.

So had to find a longer bolt the same size and just fitted a nut to the other end. Not ideal, but does the job.

All done methinks, I'll give her a whirl.

Crank crank crank - nothing. And after a few attempts, of course I've also now drained the battery. Swearing by this stage - I then glance at the fuel gauge. Nothing, absolutely empty. Dry as  the Great Sandy Desert.

When I parked her up a month ago, I know there was still some fuel in it - but after a week of +40C over Christmas, I figure what was left in the tank and fuel lines must have evaporated.

Doh - what an idiot to overlook something so obvious.

So I go and get 10L in a jerry can, pour it in and check - yep fuel gauge is now showing a quarter of a tank. So I drag out my jump starter and try again.

Same as before, crank crank crank - click click click - no start and now my jump starter needs recharging again too.

Bugger - decide to call RAC. The plug in their battery jump starter - still nothing.

So they go through the usual checks - spark yes, fuel - hmmm - still no fuel getting to the carbies. Use hand pump to suck fuel up the fuel line and try again.

After a few tries - bingo. She's Alive!!

But coolant is streaming out from the thermostat housing. I jump in to tighten up the bolts - they're tight, but still there is coolant coming out. WTF...

Then it dawns on me - back when I first removed the thermostat a month ago, I also loosened the air bleed screw. But I had only popped it back in without tightening it.

Couple of turns with the socket wrench and all tight as a drum again, no coolant leaking and engine running fine.

Take her for a spin - uh-oh, now the fan isn't coming on as it should when getting above 90C. Bugger. But i clean the thermo switch wires on the rad and clean up the power wire connection to the fan (think it got damp from coolant etc) and fan comes back on when its meant to.

Feeling smug - so I go for another spin.

And of course - thing is still bloody running hotter than it should. Even though the old thermostat was definitely buggered, the new one doesn't seem to have made a difference (surely it can't be a dud too...?). Generally now sitting closer around 85-90C in normal running, and heads toward 100C if I'm sitting stationary for more than a minute or so (even with coming on). At least its not pumping coolant out the overflow like it did a few weeks back.

So I'm back to square one. Now thinking maybe its time to yank the rad, give it a flush, and or get it refurbished/replaced

But I've got another problem - where the hell are the bolts located that hold it in place? Damned if I can see them.

Any one able to advise? My Haynes manual just says remove the mounting screws but it only shows the single big mounting bolt on the top. Where (and how many) are the others? I sure can't see any.

(Sorry the pic is not great).

[Craig_m67]

As I understand it (long, long time ago), there's just that one bolt at the top.  The bottom of the rad has two lugs that fit in holes in the rad cross member. Same as an Alfa Sud/Sprint

[poohbah]

Cheers Craig - that explains the pic in Haynes then.

[festy]

Yes, the radiator is held in by just that one bolt at the top.
If the radiator is significantly blocked, you can often tell just by getting everything warmed up (thermostat properly open) then shut off the engine and feel around the back of the radiator - it should all be vaguely the same temperature.
If you find cool spots (often at the bottom) its a sign of blocked tubes.

Running without a thermostat isn't a great idea and can give misleading results anyway, because with the thermostat removed the radiator bypass hose is always fully open. In normal operation it gets progressively blocked by the plunger on the bottom as the thermostat opens.

Many years ago I had an Alfetta cooling problem that ended up being fixed(?) by restricting the bypass hose flow by sticking a piece of garden hose inside it IIRC.
I can't remember the specifics, but something was causing the thermostat plunger to not sufficiently close off the bypass.

[poohbah]

Cheers Festy,

As a matter of interest, would the fact that air bleed screw at the top of the thermostat housing was "open" contributed to fuel not being drawn up the fuel line to the carbies?

I imagine it must - which would explain why even the RAC guys had trouble getting enough fuel into the carbies.

[festy]

As a matter of interest, would the fact that air bleed screw at the top of the thermostat housing was "open" contributed to fuel not being drawn up the fuel line to the carbies?

I imagine it must - which would explain why even the RAC guys had trouble getting enough fuel into the carbies.

No, there's no possible way those two are related.
Your fuel pump probably just needed priming, and if the fuel line is empty it can take quite a while to draw fuel all the way from the tank.

In this situation if you pop the vent covers off the tops of the carbs and tip a little bit of petrol into the bowls, the engine should then run long enough for the pump to prime itself.

[poohbah]

Doh... stupid me. For some reason  I thought it may have had a vacuum line running from it. No idea why.

[Colin Edwards]

Taking longer than usual to prime the fuel system could suggest a partially blocked filter somewhere.  If the fuel flow is restricted and lowers the carby float bowl level, the engine may be running a bit lean.  This may contribute to the overheating?