Hi, I wonder if somebody out there may be to help me with a heating problem. A while back we had some really cold weather and although I had anti freeze in the car whilst driving to work the red temp light came on, stopped the car and steam was pouring out of bonnet. I guess the anti freeze level may not have been as I thought but the result was the header/expansion tank blew a hole in it. I replaced the tank but since then my internal car heater/blower only blows cold most of the time, I put in a used matrix and a new thermostat but the only time it gets warm is at high revs, before this it was hot regardless of the engine revs. I have a Seicento Sporting, I have also tried releasing the cap to ensure no air lock and the water in the tank does get warm. Any help would be greatly appreciated. Thanks
Technical Heating Problem
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Technical Heating Problem
Hi ,
I suspect you HAVE got an airlock,
did you undo the little bleed screw(s) on the water pipes that go to the matrix ( behind the engine) ?,
on some cars it's helpful to over-fill the header tank / radiator neck to help give a little more pressure and force air out, run like this for a few mins,
without the rad cap on,
Charlie
I suspect you HAVE got an airlock,
did you undo the little bleed screw(s) on the water pipes that go to the matrix ( behind the engine) ?,
on some cars it's helpful to over-fill the header tank / radiator neck to help give a little more pressure and force air out, run like this for a few mins,
without the rad cap on,
Charlie
Right Ok, thanks, I didn't actually fit the matrix but do know where it is, so will look for the bleed screws, does the engine need to be running when bleed screws undone. I will overfill the header and run it again. Much appreciated, will let you know the results.
Stuart
Stuart
You can usually get away with doing it cold. Do the front one first, then the rear one (heater turned to full).
i've always bled mine cold, engine off. and as above heater set to full.
If you look next to the battery, you'll see two pipes passing into a rubber boot on the bulkhead. That's the heater feed and return pipes.
On the top pipe there will be a little knurled screw the size of a number plate screw. That's the heater matrix bleed screw.
With a cold engine:
Top the reservoir up to "Max" and remove the cap.
Unbolt the reservoir and unscrew the bleed screw until it's "loose" but not about to fall out.
Start the engine, turn the heater on (to open the flow valve) and then lift the reservoir up a few inches.
You should see coolant start to pulse out of the bleed screw. Let it dribble for a while until any air is expelled (catch it with a rag) and then when it seems that no more bubbles are coming out, tighten the bleed screw. Job done.
The system is self-purging and it will shift any residual air out so you don't have to have OCD about the whole bleeding process
... just get as much air out as possible.
Another technique is to get a friend to pressurise the header tank by cupping their mouth on the end and puffing into it enough to "blow" the coolant through the heater tube and then hold it under pressure while you tighten the screw up... but take great care because anti-freeze is highly toxic, so avoid getting any on your lips etc.
Best to do it the non-contact way.
Ralf S.
On the top pipe there will be a little knurled screw the size of a number plate screw. That's the heater matrix bleed screw.
With a cold engine:
Top the reservoir up to "Max" and remove the cap.
Unbolt the reservoir and unscrew the bleed screw until it's "loose" but not about to fall out.
Start the engine, turn the heater on (to open the flow valve) and then lift the reservoir up a few inches.
You should see coolant start to pulse out of the bleed screw. Let it dribble for a while until any air is expelled (catch it with a rag) and then when it seems that no more bubbles are coming out, tighten the bleed screw. Job done.
The system is self-purging and it will shift any residual air out so you don't have to have OCD about the whole bleeding process
... just get as much air out as possible.Another technique is to get a friend to pressurise the header tank by cupping their mouth on the end and puffing into it enough to "blow" the coolant through the heater tube and then hold it under pressure while you tighten the screw up... but take great care because anti-freeze is highly toxic, so avoid getting any on your lips etc.
Best to do it the non-contact way.
Ralf S.
I just wonder if all the vanes on the impeller are not mashed to peices (usual result if an engine with a frozen block is started) and, in turn, the head gasket hasn't gone. It takes quite a lot to explode an expansion tank.
I'd get a compression test done ASAP.
I'd get a compression test done ASAP.
Agreed or remove pump.
I had this problem too. I kept bleeding the heater system but I also had to keep topping up the radiator. Eventually found the heater matrix was leaking water into the passenger side carpet. Cured the small leak with a radweld liquid added to the radiator. cured the leak and restored heat back to my Fiat Bravo Mk1. Hope this helps?
Rosso187
Rosso187
Hi guys, thanks for all your advice, update on the issue. Been searching for the bleed screws what keep being mentioned but still am unable to locate them, wondered if they might be behind the firewall protection, so today being a nice day I have done the following. Since first posting on here I have tried getting rid of any airlocks and temperature got slightly better but only at higher revs. So here is todays report.
Unbolted the expansion tank and overfilled and removed cap
Started engine with blower on cold and revved engine
Turned blower to hot but no different
Took off air filter and housing (for better access)
Removed battery to try and locate bleed screws
Removed drivers side portion of firewall material
(Two pipes that go into matrix were warm from engine having been run)
Cable that operates temperature dial in car - cable clip seem loose so reattached this correctly.
Refitted everything having found no bleed screws but now temperature back to cold again.
Wonder if someone may be able to upload an image of the bleed screws and their location on the car - the only bleed I think I have found is on the firewall material central on the car and is a rubber hose with a screw in stopper on the end pointing towards the floor.
Roll on summer when I won't need it.
Unbolted the expansion tank and overfilled and removed cap
Started engine with blower on cold and revved engine
Turned blower to hot but no different
Took off air filter and housing (for better access)
Removed battery to try and locate bleed screws
Removed drivers side portion of firewall material
(Two pipes that go into matrix were warm from engine having been run)
Cable that operates temperature dial in car - cable clip seem loose so reattached this correctly.
Refitted everything having found no bleed screws but now temperature back to cold again.
Wonder if someone may be able to upload an image of the bleed screws and their location on the car - the only bleed I think I have found is on the firewall material central on the car and is a rubber hose with a screw in stopper on the end pointing towards the floor.
Roll on summer when I won't need it.
the one behind headlight is the more important of the two, the other one is just for the heaters inside.
Hi
The auto should bleed, easily cold, or mine does.
I normally use a proprietsry rad flush as the instructions on the package and remove both bleed screws (there is an O ring in each and poke with a knotting needle or similar.
Then add deionsed water and coolant to just over bottom of the header tank with the headlamp bleed open then screw on the header tank cap tight then squeeze a hose with the bleed valve just open, tighten bleed screw, with pipe still squeezed and open header cap, release hose squeeze, when cap is loose, then tihten cap and open bleed again. The squeeze will remove some air...
Repeat until you get drips.
Do the same for the matrix bleed screw.
The next step is optional, Leave the header cap closed and matrix bleed open with a little coolant in header tank, run engine for five minutes until coolant dribbles out of matrix bleed tighten bleed.
Top up header tank to normal level marker.
I never bother running the engine, the reason you have the header empty is that if you run the engine the air in the header is heated first, from the little pipe going into the header and the more air in the header the more air/water you will expel from the matrix.
But I dont do that step, squeezing pipes is easier.
Noel
P.S. I'd still change garage
The auto should bleed, easily cold, or mine does.
I normally use a proprietsry rad flush as the instructions on the package and remove both bleed screws (there is an O ring in each and poke with a knotting needle or similar.
Then add deionsed water and coolant to just over bottom of the header tank with the headlamp bleed open then screw on the header tank cap tight then squeeze a hose with the bleed valve just open, tighten bleed screw, with pipe still squeezed and open header cap, release hose squeeze, when cap is loose, then tihten cap and open bleed again. The squeeze will remove some air...
Repeat until you get drips.
Do the same for the matrix bleed screw.
The next step is optional, Leave the header cap closed and matrix bleed open with a little coolant in header tank, run engine for five minutes until coolant dribbles out of matrix bleed tighten bleed.
Top up header tank to normal level marker.
I never bother running the engine, the reason you have the header empty is that if you run the engine the air in the header is heated first, from the little pipe going into the header and the more air in the header the more air/water you will expel from the matrix.
But I dont do that step, squeezing pipes is easier.
Noel
P.S. I'd still change garage
Has the heater valve melted not allowing any flow to warm up , ive been told this is a common fault on an over heated engine , can't see any guides on changing heater matrix and valve ?
There are no guides: if you want one, write one.
It can't have melted the heater valve -- at, what 120C?
I suggest, as before, look at the water pump, get it compression tested. Expansion tanks do not explode for no reason -- something catastrophic has occured.
It can't have melted the heater valve -- at, what 120C?
I suggest, as before, look at the water pump, get it compression tested. Expansion tanks do not explode for no reason -- something catastrophic has occured.
did my heater matrix, lo ly heat for the winter, and mow can turn right off for summer , bliss.
Had to stut bracce off, battery out , and fuse block then the felt bulk head cover. Had too bend the bracket down that held the fuse block so to slide the matric out.
Had to stut bracce off, battery out , and fuse block then the felt bulk head cover. Had too bend the bracket down that held the fuse block so to slide the matric out.
