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Alfa Romeo 145 - 146 Forum > Technical > FAQ
mattk1
Hey guys,

Following on from this thread http://forum.alfa145.com/index.php?showtopic=8447

I have been regularly using (sorry for not updating by the way) the 145 and am happy with it, clutch all sorted smile.gif

Im just getting round to fixing the problem with the heaters. Ive done some testing and can confirm that both radiator pipes get hot, but i still get no heat in the cabin.

I stripped out some of the dash today to get a better view and found the two pipes that come in from the engine bay. These two dont get hot;

[attachment=8880:HeaterBo...rolCable.jpg]

Is it likely to be the heater core that has failed?


Any help would be greatly appreciated! biggrin.gif
GialloEvo94
If those two pipes aren't hot then there is no circulation going through your heater matrix (the thing they are connected to). Check that the cable which operates the hot/cold setting is actually operating the lever correctly on the heater box (it's that blue cable in your picture). If it does seem to be working lever okay then the most likely cause is that the mechanism between that lever and the hot water valve is knackered, the hot water valve isn't opening at all for some reason, or the valve has seized. The valve is the black thing that pipe 2 is connected to.
mattk1
Hey GialloEvo94,

Thank you for the reply smile.gif

The cable which operates the hot/cold setting does move when i turn the dial.

So you think its the heater valve? Is that an easy job by any chance? Im keen to get my car back in one piece blink.gif
GialloEvo94
I've never had it it pieces so I don't know exactly how the valve works or how the mechanism between the cable and there lever actually operate the valve. If it looks like the cable mechanism is operating fine then it might be worth taking that valve out and seeing if there is anything obviously wrong with it. You will need to drain the cooling system first though unless you want a passenger footwell full of coolant biggrin.gif

The valve itself is only about a tenner including VAT from Alfa (part number 7754042). Number 5 in the following diagram...

[attachment=4288:EPERHeaterMatrix.jpg]
purple
I have done the cable on this job and it is a bit fiddly buy is DIY able, but the passenger airbag has to come off and be powered down beforehand, there is just loads of screws to undo.

The diagram does not clearly show there is a connecting rod between the end of the cable and the valve. This has a screw in the middle and allows for some adjustment, check it has not fell apart and the bottom half of the arm valve is visibly opening and closing. If all appears to be working well, the other thing to check is that there is another flap that shuts the airflow over the matrix, this is how the heater responds straight away to being shut off rather than cooling down over time. It may be instead of wokring simultaneously, the flap is not moving so the valve opens but the flap is not moving out of the way to allow airflow, on a correctly functioning sytem it is possible to hear it.

The Haynes manual for a Bravo/Tipo may be of help as it does describe the sytem quite well.

HTH
purple
guide CMA did here is good, some of the picture have gone AWOL though

http://forum.alfa145.com/index.php?showtop...9&hl=how+to

HTH
purple
you can see on here, three cable, one for the temp, one for the direction and the other to shut off the flap

[attachment=4289:heater_cable.jpg]

are all three intact?
GialloEvo94
QUOTE(purple @ Sep 29 2006, 11:21 AM) *
The Haynes manual for a Bravo/Tipo may be of help as it does describe the sytem quite well.

I put a link to the PDF scans of the Haynes Manuals HERE.
mattk1
Hey guys,

Many thanks for the helpful replies, unfortunately i've had to leave off the heating problem as another more serious problem occurred today.

See this thread:

http://forum.alfa145.com/index.php?showtopic=8612


sad.gif
mattk1
Right, engine problem sorted so i can get back to my heating problem now..


QUOTE
you can see on here, three cable, one for the temp, one for the direction and the other to shut off the flap. Are all three intact?


I had another look earlier and can confirm that all cables are working and connected as they should be.

I did some more tests today and it sounds like everything is working.

The flow direction dial works, fan speed dial works, the hot/cold dial changes noise slightly as i turn it, air recirculation button works and the air con light comes on.

I should mention that the air con doesnt blow ice cold air, in fact it doesnt de-mist the windscreen when i switch it on. However, i pressed the two valves on the pipes under the bonnet and gas under pressure did release..

But still no heat! blink.gif
GialloEvo94
You need to try and work out how the mechanism works between the cable operated mechanism and the hot water valve (that black thing I mentioned earlier). I don't know how it works so I'm doing a bit of a blind diagnosis but I suggest you drain the coolant in the engine (pull the bottom hose off the radiator) then take the pipe off that valve (have a rag handly to catch any dregs of water left in it to save your carpets). Then unbolt and remove the valve assembly from the heater matrix. It might be immediately obvious what is wrong or it might not . All you can do is take it apart and try to see. Be aware that there is a sealing gasket in there (number 4 in the diagram I posted in my previous post). If it's a rubber 'O' ring you will be able to reuse it but if not then you will need a new one before putting everything back together again.

Take it apart and let us know what you find. Some decent photos would also be good if you can do some as it's an area of the car that not many people have done any maintenance on.
purple
QUOTE(mattk1 @ Oct 2 2006, 05:54 PM) *
Right, engine problem sorted so i can get back to my heating problem now..
I had another look earlier and can confirm that all cables are working and connected as they should be.

I did some more tests today and it sounds like everything is working.

The flow direction dial works, fan speed dial works, the hot/cold dial changes noise slightly as i turn it, air recirculation button works and the air con light comes on.

I should mention that the air con doesnt blow ice cold air, in fact it doesnt de-mist the windscreen when i switch it on. However, i pressed the two valves on the pipes under the bonnet and gas under pressure did release..

But still no heat! blink.gif



have you let the car reach temperature and felt the pipes going into the heater matrix on the inside of the car?
purple
GE, could you possible post up picture 5/6 of the heater parts, (I cannot seem to do it off the disc, not that computer literate)

you will see that the cable IIRC connects to No 6, lever when that moves it pulls both rod 7 (which in turn pulls the valve open) and moves lid 1 at the same time. lever 6 may not be gripping on the spindle for lid 1

rod 7 is also in two parts held with a self tapper, check it hasn't come apart and it does actually move the valve in GEs previous picture 6/6.

if all that is OK I would suspect the valve had failed internally.

If you're aircon does nor clear the screen the main suspect will be the recirculation flap, often the motor will make the right noise but the flap is stuck in the closed position, just needs snapping off the rod. Its access from out side the car, have to take the plastic scuttles under the wipers off, remove a plastic shield on the passenger side and peer down the air intake, you can then see the flap.

Matt sounds like you have done the hardest bit, stripping all the bits off, its just the last little bit thats being elusvie, at least the parts are cheap and think of the laour you have saved. smile.gif

HTH

GE thanks in advance
GialloEvo94
QUOTE(purple @ Oct 3 2006, 10:53 AM) *
GE, could you possible post up picture 5/6 of the heater parts, (I cannot seem to do it off the disc, not that computer literate)

Here you go..picture 5/6 (new) and 6/6 (same picture as in my previous post) biggrin.gif

[attachment=4307:EPERHeaterParts5.jpg]

[attachment=4288:EPERHeaterMatrix.jpg]
purple
how do you do that so fast!

hopefully the description beforehand makes sense
mattk1
Hey guys,

Thanks for the replies! biggrin.gif

Purple, i think you have hit the nail on the head. The rod that opens the valve is completely missing!

At first glance i could see that the blue cable hadnt snapped so assumed it was working. However on removing the valve, i could see that there should be a connecting rod between the blue cable and the valve:

[attachment=8881:HeaterBo...bleLever.jpg]
[attachment=8882:HeaterBo...rolLever.jpg]

wink.gif

I wonder if its fell off and is hidden inder the carpet somewhere?

If not, is that rod available seperately from a dealer? Seems strange that its completely missing.. wink.gif
mattk1
UPDATE:

Looks like i also need a new valve. I took the valve off and tried blowing through it but couldnt fell any air going through.

I then hooked up my air compressor to it and turned it on full whilst moving the valve lever, but still nothing.

So i decided to cut the top off the valve and look inside and sure enough, the cover plate which blocks the hole had snapped at the point where the lever moves it:

[attachment=8883:HeaterBo...tedValve.jpg]

Are these parts only available from main dealers? wink.gif
GialloEvo94
Nice one smile.gif Sounds like the valve probably seized, and the force on the rod which could no longer stand the force of trying to open the seized valve probably then just snapped or came unclipped and fell out. The previous ovner probably found it in the passenger footwell, didn't know what it was so just chucked it away no3.gif

Dealer only parts I'm afraid. Fortunately they won't break the bank smile.gif Alfa part numbers below:-

Rod (number 7 in 1st diagram of post #14) -> 7603139 (1 including VAT)
Valve (number 5 in 2nd diagram of post #14) -> 7754042 (10 including VAT)

I also advise you get a new sealing gasket (number 4 in the 2nd diagram)...part number 7619390 which is 3 including VAT (more than the rod for a tiny 'O' ring ohmy.gif).

If you need to run your car before the parts arrive then just block up the ends of both pipes with a blanking plugs (suitable pieces of metal rod the right size will do) or put in a 'loop' tube to connect the two pipes together (not sure if standard small diameter copper plumbing pipe would fit but worth a try) smile.gif

At least we now have a decent explanation as to how it all works (thanks to purple thumbsup.gif) and some pics...even if some of them are just a blur tongue.gif (macro mode usually helps wink.gif)
purple
Matt, great that you've got it and it will not cost too much in partss, just a few skinned knuckles eh?
mattk1
Big thanks for the help on the forum guys biggrin.gif

Parts are now on order and should have them on thursday. Fortunately i dont need to use the car in between..

Apologies for the less than cyrstal clear pictures, i only had my phone camera to hand biggrin.gif

Will post back with an update when i get my parts..

Oh just one thing, when i come to refill the coolant, how many litres of anti freeze do i put in??

Thank you!
GialloEvo94
QUOTE(mattk1 @ Oct 3 2006, 05:10 PM) *
Oh just one thing, when i come to refill the coolant, how many litres of anti freeze do i put in??

Look here smile.gif
mattk1
Hey guys,

Had a phone call from the dealer i ordered my replacement parts today, no problems getting the heater valve and gasket, but the tie rod they wont have until 10th October sad.gif

So im in the process of trying to make my own, figured how hard can it be since the genuine rod only costs 1.00!

Im using a wire coat hanger for the job and so far ive managed to secure it to the heater valve lever.

Problem i have is that there isnt enough room for me to attach it to the top half. Would be alot easier if i could take off part 6 in the diagram but i cant see any screw holding it on, and didnt want to just pull it incase it damaged the flap inside:

[attachment=8884:HeaterBo...dDiagram.jpg]

Does anyone know how it comes off?? huh.gif

Cheers! smile.gif
purple
QUOTE(mattk1 @ Oct 4 2006, 05:29 PM) *
Hey guys,

Does anyone know how it comes off?? huh.gif
Cheers! smile.gif


its a few years since I did mine and while I remember getting my hands shredded by the sharp edged plastic the exact 'what bit fits on what' maybe getting a bit blurred blush.gif

IIRC that part is on the end of the axle that is attached to the flap so will be hard to remove without breaking it, or worse still the flap.

For the sake of 1 I would leave it until the 10th, unless you are passing a scrap yard with a Tipo/Bravo, as the system is the same and they all should use the same rod.

HTH
mattk1
Ahh right!

I didnt know the Tipo/Bravo used the same system smile.gif

I'd thought about going to a scrapyard for it but imagined the chances of me finding a 145 were slim (hardly ever see them on the road even!)

Much better chance of finding a suitable Fiat biggrin.gif


QUOTE
For the sake of 1 I would leave it until the 10th


Thing is, i dont fancy leaving the dash out too long or i'll forget where everything went laugh.gif (and im too impatient) tongue.gif


Cheers guys!
purple
if tempted to use it, you must put the airbag back in, connected, otherwise when you turn the ignition on the airbag light will come on and thats a dealer reset and 50 ish gone.
mattk1
Hey guys,

Just to update, my heaters are now in full working order and my car is back in one piece biggrin.gif

Was a nerve racking moment when i had no heat for ages (even when it reached normal operating temp) but then eventually it came through and is working great now!

Guess it just needed a good blast..

Thanks for all the help on here, really has been most appreciated biggrin.gif

Cheers!
GialloEvo94
QUOTE(mattk1 @ Oct 5 2006, 09:01 PM) *
Just to update, my heaters are now in full working order and my car is back in one piece biggrin.gif

Nice one thumbsup.gif Another success story biggrin.gif
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