Technical Heater not blowing warm air

[Ucof]

Hello everyone,

Im only with access to a spares/ repairs Uno for the next 24 hours as I'm at my dads house before returning back to Wales.

For ages now, my Uno 1.0 has only been able to blow cold air out the vents. Engine warms up to a nice temperature and will stay there, but absolutely no warm (to any degree) air is blown out the vents. Have tried the fans knows and dials on all possible settings but still no joy.

Coolant level is fine and the car recently came back from a service where all fluid levels were topped up.

Any ideas where to look or where to start troubleshooting?
With winter drawing in, I really want to get this sorted ASAP. I've started to lose feeling in my toes on some days because it's been so cold.

Thanks in advance.

 

[alexGS]

Hello Ucof,

I'm in Portishead at the moment. With a maximum temperature of 3 degrees today, I feel like I've stumbled into a fridge whenever I go outdoors!

So it must be horrible to drive an Uno with no heater in these conditions.

Find the heater valve on the right end of the heater radiator, under the dash - one of the two heater pipes attaches to this valve. Make sure that the lever moves correctly when you turn the heat adjustment knob. If it has broken off or worked loose, you should be able to fix that without any further dismantling.

Otherwise I suggest you drain the cooling system, then get a plastic bowl and put it under the heater, then remove the valve (two 10mm nuts). That is the surest way to inspect the valve and make sure it opens and closes properly. There are two types of valve; a rotating type, and a sliding type. I've never decided which one is 'later' or 'earlier' design, or even which one is better. The important thing is that the valve should work!

After you refit the valve and before you fill the cooling system, disconnect the heater hoses in the engine bay (one connects to a long hose that goes to the radiator bottom hose, the other connects to the cylinder head I think, but I can't quite remember) and use a garden hose (assuming it's not frozen!) to flush water through the heater in both directions. If the valve has been jammed closed, expect lots of rusty water in there - get it running clear. I think you would want to wear gloves for this job!

Make sure the valve is still open when you fill the cooling system - some Unos have a plastic air bleed valve in the pipes that connect the heater, and if so, that should be open too. There is another air bleed on the radiator itself. Leave the pressure cap off and keep a watch on the coolant level as the engine warms up (it will drop suddenly as airlocks are filled), remember to add enough antifreeze, and best of luck...

The Uno heater is not a terribly complex thing by modern standards, so I'm sure you can get something working soon from the spare parts that you have. Best wishes!

-Alex

 

[Ucof]

Fantastic Alex, thanks for the advice. Once again, you are a wealthof knowledge and advice.
Most appreaciated

Am tempted to go and have a look at it now.. however, it is dark... and I am warm


Portishead UK? I couldn't fin one in NZ, so I assume Im right.
I'd love to come and say hello if you are
It not too far a detour for me on my way home (London to Swansea)

 

[alexGS]

Yes - Portishead on the sea-side of Bristol

Chosen just because it was within striking distance of where I have to do a job in the week - but in the meantime I should be holed-up here getting some work done.

Let me know how you get on - I guess I'm not really any help at all (I don't think the Premier Inn would enjoy the idea of the carpark becoming a workshop) but sure we could meet up - I'll send a PM.

Cheers,
-Alex

 

[Ucof]

Alex is my new best friend


Turns out the problem was that the valve under the dash board has broken, whereby turning the cable made no difference to the temperature as the fixing at the end of the cable from the temp dial had sheered off from the disc inside the valve, meaning that the valve was shut and there was no way to move it.

With many thanks to Alex, and after buying a few new tools, we took the valve apart and rotated the disc with a thin screw driver, so now, it is permanently open!

We did bleed the water pipes however too and it seemed like there was a bit of an airlock in the system too.

It was so good going home with warm feet Alex!
Thank you!

 

[turbo_jim]

Just for info, you can still buy this valve from Fiat. I bought one last year for a 1992 uno and cost about £8 i think.