Ask An Expert!

[hellmett]

Righto!

Got a few quickies for the diesel heads amongst us!

I have TOTALLY flushed and cleaned the cooling system and the matrices for both the heaters separately.

I put in a NEW thermostat and replaced the radiator cap with a NEW one.

There isn't a tiny speck of dirt in the system now at all.

I have refilled it with quality coolant and ran the vehicle etc. but still I cannot get NO heat coming from either of the heaters?

I can't fathom it?

I am correct in summising that this time, it is DEFINITELY an airlock causing this?

I also noticed that before I changed the thermostat I could flush the system via the top hose both ways, after I changed the thermostat it seemed as if it was BLOCKED and seemed to be building up pressure when I was flushing with the hose attached with a very tight hose clip to the top hose!

Was this "block" because my new thermostat was working correctly and my old thermostat was knackered, and had locked fully open when I was flushing before?

When thermostats break do they lock open?

After checking the rubber hoses to the rear heater in the engine bay below the air box I noticed that one of them seemed "solid" and the other one was able to be pinched and pretty flexible.

As water seemed to only be getting through one of them to the rear matrix would it be a good guess that this solid pipe is buggered and is solid because it is blocked with ****?

Can anyone advise?

I really appreciate the advice from you all!

Thanks again!

Gary

[TonyN]

After checking the rubber hoses to the rear heater in the engine bay below the air box I noticed that one of them seemed "solid" and the other one was able to be pinched and pretty flexible.

As water seemed to only be getting through one of them to the rear matrix would it be a good guess that this solid pipe is buggered and is solid because it is blocked with ****?


Gary

You may find the matrix is block, the hard pipe is pressureised cos the water can't get out the other end of the matrix.

Is the hose going to the main heater hot? and isthe valve working propely, ie cable not snapped and valve staying shut.

[hellmett]

Re

Both the matrices are free and the water is able to flush both ways freely (took your previous advice and flushed the **** out of them by disconnecting and flushing both ways about 10 times!!!)

I know that one of the pipes to the rear heater is blocked somewhere but I was thinking it was the rubber hose because of how solid it was (even under extreme pressure I cannot see it being so solid as to be hard as a rock!!!)

The hoses going to the main heater are warmish!

The hoses going to the rear heater are stone cold!

Gary

[TonyN]

Have you had a head go in the past? Exhaust gases corrode the water ways if its left to long, you may find rust flakes have built up in the smaller pipes and blocked them. I often find some of the hoses are 'crunchy' when you squeeze them.

[hellmett]

Re

I think the head went about 2 1/2 years ago.

Some of the pipes are crunchy but I will change them as soon as I can.

Do you think my suspicions are correct in the first post?

Gary

[TonyN]

It could still be a airlock, have you pulled the hose slightly off the main heater valve in side with the car is idling, to make sure water is getting to the heater, this normally clears most airlocks, as its the highest part of the system. It'll also prove the pump is working properly.

If the car warmed up properly, you should find when its cold tomorrow you can get more coolant in it. As long as your are running it long enough to let the stat open, the top of the rad should be hot, all the way along.

If the heater pipes are still cold, feel back along the pipe from the valve, to the metal pipes along side the turbo, then across the front of the motor to where they go into the thermstat housing. The top hose goes to the heater, so it should be hotter than the other one.

[hellmett]

Re

It could still be a airlock, have you pulled the hose slightly off the main heater valve in side with the car is idling, to make sure water is getting to the heater, this normally clears most airlocks, as its the highest part of the system. It'll also prove the pump is working properly.

Can you explain this a bit more Tony?

It sounds like you want me to pull a hose off inside the car, is this the case?

Or is it the hose beside the heater open/shut valve?

Do most airlocks gather here?

How will it prove the pump is working?

I looked in the rad cap and there was a lot of turbulance, does this show pump working?


Gary

[TonyN]

Can you explain this a bit more Tony?

It sounds like you want me to pull a hose off inside the car, is this the case?
Or is it the hose beside the heater open/shut valve?
Do most airlocks gather here?
How will it prove the pump is working?
I looked in the rad cap and there was a lot of turbulance, does this show pump working?


Gary

Nah, on the bulkhead is the heater valve, check its actually opening and closing when you move the lever in the car, you see the end of the cable on the valve. if you gently pull the hose off the right hand side off the valve, you should get coolant coming out, this will prove water is reaching the heater not air, and show the pump is pumping to the highest part of the system.