HELP WITH COOLING SYSTEM

[Grumps]

Different car I know Martin but Jues car was loosing the header tank worth of coolant over the week with no sign of a leak and no over heating, the cabin was freezing cold. I spoke with Tony and I found a valve in one of the pipes going from the engine bay into the cabin, I turned it to open till water came through, closed it off and topped the header tank back up and bingo, no water loss and a warm cabin. I realise it's not the same but I think it's a air lock/ blockage rather than head gasket related mate.

 

[Stevo7682]

Different car I know Martin but Jues car was loosing the header tank worth of coolant over the week with no sign of a leak and no over heating, the cabin was freezing cold. I spoke with Tony and I found a valve in one of the pipes going from the engine bay into the cabin, I turned it to open till water came through, closed it off and topped the header tank back up and bingo, no water loss and a warm cabin. I realise it's not the same but I think it's a air lock/ blockage rather than head gasket related mate.

Zed doesn't have a valve to restrict the coolant to control the temp that is done by a flap in the heater box .
Unfortunately Matrin i reckon your matrix will need to come out but also unfortunately means entire dash out then heater box unbolted from bulkhead to gain enough room to remove it

 

[Jack Ratt]

Question ......... Could contamination from the heater matrix work free and then block a water channel in the engine block ?

If so, could this in turn lead to the engine overheating ?

 

[Mazza]

Just a thought..

Is there a solenoid switch on the 2.8lt heater system that controls the flow of water through the heater matrix. They are on the 1.9lt version like mine, and these can fail in the shut position.

 

[Tracy Dee]

I had a Triumph Pi back in the day exactly the same thing the heater matrix was corroded full of crap really blocked. I put a really strong treatment in the system can't remember what it was but it was strong stuff.
Let it run for an hour then flushed system back flushed it the rust that came out was unbelievable.
But the heater worked after that.
Cliff.

 

[Mnbrennan]

Just a thought..

Is there a solenoid switch on the 2.8lt heater system that controls the flow of water through the heater matrix. They are on the 1.9lt version like mine, and these can fail in the shut position.

Yeah there is a heater control valve. Assume this is working as I get heat when on the move

 

[t-tony]

I would definitely be trying more than one type of coolant system flush before raving the matrix out for sure.

Tony.

 

[Stevo7682]

I would definitely be trying more than one type of coolant system flush before raving the matrix out for sure.

Tony.

Half to agree with Tony even when you get the dash out my heater box looks like its bolted on from the engine bay side

 

[NZ00Z3]

Zed doesn't have a valve to restrict the coolant to control the temp that is done by a flap in the heater box .

I don't believe this to be true. There is a heater valve. In my 2L Z, when dropping the gear box mount down to remove the gear box, I had to ensure that there was a gap between the inlet manifold and the heater valve mounted on the fire wall. The rubber diaphragm in the heater valve can turn to mush resulting in no heat.

I'm still in the "air bubble in the cooling system" camp, as Martin's car has no heat on idle and good heat on rev's. The difference is water pressure from the water pump pushing the water past an air lock. Have read many posts on various forums of cars with the same symptoms which were sorted by bleeding the air out of the system.

 

[Stevo7682]

I don't believe this to be true. There is a heater valve. In my 2L Z, when dropping the gear box mount down to remove the gear box, I had to ensure that there was a gap between the inlet manifold and the heater valve mounted on the fire wall. The rubber diaphragm in the heater valve can turn to mush resulting in no heat.

I'm still in the "air bubble in the cooling system" camp, as Martin's car has no heat on idle and good heat on rev's. The difference is water pressure from the water pump pushing the water past an air lock. Have read many posts on various forums of cars with the same symptoms which were sorted by bleeding the air out of the system.

On the m43 and m44 1.9 ( without air con ) doesn't have a valve.

Although when you go into the air con section on real oem it does show a valve

But on the 4 cyl engine it must only be fitted with air con as both ours definitely dont have one

 

[NZ00Z3]

Hi @Stevo7682 , I stand corrected with the 4 cylinder cars.

I don't know if Martin's 2.8 Z has air con or not? Being a 2.8 Z I suspect that it does as they tended to be well spec'ed car when delivered new.

 

[Grumps]

Not necessarily @Murray Wall. My 2.8 doesn't have air con..

 

[Mnbrennan]

Hi @Stevo7682 , I stand corrected with the 4 cylinder cars.

I don't know if Martin's 2.8 Z has air con or not? Being a 2.8 Z I suspect that it does as they tended to be well spec'ed car when delivered new.

No air con, but does have a heater valve

 

[Stevo7682]

No air con, but does have a heater valve

Can you bypass the valve in any way to rule it out

 

[Stevo7682]

This is the view out my window this morning trying to deal with same thing

coolant drained flushed with water .
Chemical descaler added ran up to temp now waiting for it to cool enough to drain .
But i have already removed the matrix ( slightly unconventionaly ) as it had very little heat at any speed so i am hoping todays endeavour will further improve things.

 

[Mnbrennan]

This is the view out my window this morning trying to deal with same thingView attachment 71949coolant drained flushed with water .
Chemical descaler added ran up to temp now waiting for it to cool enough to drain .
But i have already removed the matrix ( slightly unconventionaly ) as it had very little heat at any speed so i am hoping todays endeavour will further improve things.

Those colours look great together

Just been out again and the water temp keeps giing up again. It was fine yesterday!

This happened after I syphoned off some water from the expansion tank to get it to the right level. The same thing happened after I bled the car with stacey they other night and the expansion tank level dropped

 

[Stevo7682]

Those colours look great together

Just been out again and the water temp keeps giing up again. It was fine yesterday!

Thanks Martin.
Are you sure you've not got an airlock ?

 

[Stevo7682]

If your valve not working right could be airlocked in the matrix

 

[Stevo7682]

This is what came out of lynne's after i drained the descaler .
Bearing in mind i had drained it flushed it through various hoses 5 to 10 mins a go system filled with water (no anti freeze ) and descaler which is also clear

 

[Bozzy]

Been thinking about changing the coolant but it looks like it could be far more hassle than it's worth.
Good luck Stevo and Martin, hope you get the problems sorted.