Cold Heating In My 300 TDi Discovery MK1

[CJ1]

I have a receipt with my car that shows that the car had a new heater matrix a few months ago, the heating was working but if it was put on full and hot the engine temperature would drop and the heating would go luke warm.

My radiator was then replaced with a few pipes, and as part of it as a precaution I had the thermostat changed, however when the thermostat housing was taken apart, there was no thermostat inside. So the new one was fitted, the cooling system was flushed without the engine running and the mechanic went off home.

I left the Discovery on tickover for a while, the temperature gauge rose but when I put the heating on, it felt like Ice Cold Air Conditioning was on. I don't have air con in my Discovery.

Could this be an air lock?

[CwazyWabbit]

Could be, I've never had my 300 tdi engine get warm without driving it though to be honest .... maybe I have never waited long enough, although I'd never expect it to warm up standing still in this weather. I wouldn't expect any heat from it without the engine having been worked though, at least that is my experience of 300 tdi's in a defender which is the same beast apart from the matrix.

[landroversforever]

You need to drive it to put enough heat into the engine for the heater to stay hot.

[jad]

while u have ur auto gearbox problems is it wise to run the engine at all? Can you knacker the torque converter with a serious lack of oil even if standing still?

Jad

[western]

possible air lock,

[CJ1]

I wouldn't have thought the gearbox would be affected just by the car sitting in park, but the engine temperature gauge reached the normal running temperature I used to achieve when driving it for a while when I tried the heating.

[CwazyWabbit]

I wouldn't have thought the gearbox would be affected just by the car sitting in park, but the engine temperature gauge reached the normal running temperature I used to achieve when driving it for a while when I tried the heating.

You will be spinning a number of bits of the gearbox whilst in park surely? I would have thought the torque coverter would be spinning and the oil pump. Does your gearbox have oil in it at the moment?

EDIT: I'm not an autobox person so wait till an adult comes along to confirm.

[CJ1]

I didn't think of that, but since the Radiator was fitted the car hasn't been run or driven. And there is a very small amount of oil in it still luckily.

[PaulN]

Could well be an airlock.

We had real trouble on our current Disco but no trouble on the old one but why no idea they looked the same.

Why an engine design includes a header tank that is on a level with or below some of the heater cooling pipework and bleed points is beyond me.

We had to take of the header tank and support it higher than highest pipes - the ones at the back of rocker cover.

We pushed water into heater matrix by garden hose by removing hose to rear of block and watch for water to come out of metal pipe fore return at front of head and then to swiftly refit.

Two things you then know - flow through heater matrix and very little air in that part of circuit.

Makes sure elevated header tank has strong antifreeze mix and is full (get someone to hold) and start engine and blast and blip revs.

When engine is cold make sure that there is a return/bleed turbulence in header tank via 'Y' bleed return pipes that go into base of header.

Run up speed on engine and blast water around whilst occaisionaly looseneing first rad bleed plug and then stat bleed plug to lose air as it comes round.

Hopefull most that's left will end up in header to be replaced by fluid. We even had to loosen the heater matrix return pipe from head to allow air to purge by just slipping pipe off 'till water flowed without hissing.

I'd say it's best to have a helper and to also park truck on an angle (block or uneven ground) so that the front and header tank side is higher than engine.

Remove fan before you start to help warm up and do under cover if you are able (with plenty ventilation) to aid warm up.

You wil soon see if an airlock was the problem for a cold heater and if the matrix is working as the flo and return pipes will feel diff temps and the interior will be warm but in this weater use slow speed fan to remove cooling effect of low air temperature!!

When stat opens (make sure correct spec stat) slow to tick over it should self bleed couple with a tentative slight openeing over bleed bungs (only if brass tho)

Check strength of a/freeze.

That's wot we did anyway - HTH a bit!

[jad]

and make sure the car is on a level surface.... I have to say I have never had a problem with airlocks. I take all the caps off fill through the top most plug. When the rad is full cap it off when the header tank is at the right level put the cap on. Fill the engine and then take a heater pipe off one end and run through that until coolant comes out the matrix. Thumb over put it back together and bobs your uncle!

Jad