Heaters

Will a TD5 heater fit a 90? Thinking that it would buyt just checking if anybody knows for sure. Also are TD5 heaters better than 90 early Defender units.

As my heater fan has burnt out wondered if a TD5 was a upgrade to a better unit.

I doubt there much better if any, maybe the newer ones (2002 on) are. Mine is 1999 and its hopless, I dont know if they will fit.

mine is the original 1984 one, and its great! search on here if you want cos theres hunderds of recommendashuns for making them good.

Mine was great loads of heat its just that the electric fan has gone and bust that was thinking that maybe the later TD5 ones were better. If not i'll just get a replacement electric motor for it.

hi i have early 90 ill post pics of my heater upgrade soon using td5 blower and another smiths little motor twin motor kicks out some serious heat now ill post soon ps easy to do.

That will be interesting to see as i was going to make another heater for the back, thinking of "T"ing into the heater water pips and make a box up with another fan to take another heater matrix.

If it's burnt out just replace the motor on the blower, easy job.

My heaters were warm but dint have much blow power but now they blow really intense loads more power probly triple the power I'll post pics at weekend as I work away

my old 300tdi kicked out more heat than my 1999 TD5 does wiv a rad muff fitted.

Now if you fit a Rad Muff to a TD5 doesn't that block off the airflow to the intercooler? I thought that 'second rad' was an oil cooler until I got to thinking how big it is.

You used to be able to get radiator blinds on a kind of roller blind mechanism that you could control from inside the car. Has anyone any experience of these? Me thinks one dunk in the mud and they'd be shagged!

jzcktv said:

Now if you fit a Rad Muff to a TD5 doesn't that block off the airflow to the intercooler? I thought that 'second rad' was an oil cooler until I got to thinking how big it is.

You used to be able to get radiator blinds on a kind of roller blind mechanism that you could control from inside the car. Has anyone any experience of these? Me thinks one dunk in the mud and they'd be shagged!

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I haven't noticed any performance loss with it fitted. I actually got the temperature up to 94 degs C a couple of weeks ago going up a long hill on a dual carriageway. I had to pull over and check everything was ok cos It's the first time I have had the temperature that high and the heater has thrown out hot air. If I am going laning or am driving a long journey I drive with my diagnostic plugged in. I'm gonna try removing the radmuff and viscous fan next week so I can compare the difference between the 2 setups.

94 Degrees, was that you or the Landy... I thought you might have been pushing it uphill!
I was thinking of one of those roller blind muffs between the Intercooler and the Rad. But what I'm really thinking is that Messers Land Rover & Co. just didn't want that TD5 motor getting above about 75 degrees (if that coz I aint measured it, but it aint 'ot!)

jzcktv said:

94 Degrees, was that you or the Landy... I thought you might have been pushing it uphill!
I was thinking of one of those roller blind muffs between the Intercooler and the Rad. But what I'm really thinking is that Messers Land Rover & Co. just didn't want that TD5 motor getting above about 75 degrees (if that coz I aint measured it, but it aint 'ot!)

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I can't see how they would differ to a radmuff on the outside to be honest as the air would have nowhere to go it'd still have the same effect of restricting the flow.

The main reason for getting mine was to stop salisbury mud clogging up my rad and intercooler. (I had a near miss with my 300tdi). It has been invaluable during this cold snap though. It has enabled me to get a whole 1-2 degs extra out of my heater.

72-74 degs i what mine usually sits at when I'm driving (according to the diagnostic). 59-63 is what it stays at on tickover.

I'll check the temp on mine and see how it compares. I know it's the slowest veehickel I have ever had to heat up and when it does it doesn't get 'hot'. I can leave my hand on the top hose when it's hot and I'm no Fanny Craddock (you have tgo be 50 or over for that one)

jzcktv said:

I'll check the temp on mine and see how it compares. I know it's the slowest veehickel I have ever had to heat up and when it does it doesn't get 'hot'. I can leave my hand on the top hose when it's hot and I'm no Fanny Craddock (you have tgo be 50 or over for that one)

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I might get another thermostat and try that but the one thats in there is only 4 or 5 months old. As they have 2 valves I rekon that the bypass valve that operates at 1500rpm plus is the reason that it takes so long to even think about warming up.

jzcktv said:

I'll check the temp on mine and see how it compares. I know it's the slowest veehickel I have ever had to heat up and when it does it doesn't get 'hot'. I can leave my hand on the top hose when it's hot and I'm no Fanny Craddock (you have tgo be 50 or over for that one)

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yeah cos it would have been her 100th birthday today

ratty said:

I might get another thermostat and try that but the one thats in there is only 4 or 5 months old. As they have 2 valves I rekon that the bypass valve that operates at 1500rpm plus is the reason that it takes so long to even think about warming up.

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Just been reading the coolant section in the TD5 workshop manual from the RAVE I downloaded last night.

Thermostat - Main valve
The thermostat is used to maintain the coolant at the optimum temperature for efficient combustion and to aid
engine warm-up. The thermostat is closed at temperatures below approximately 82 °C (179 °F). When the coolant
temperature reaches approximately 82 °C the thermostat starts to open and is fully open at approximately 96 °C
(204 °F). In this condition the full flow of coolant is directed through the radiator.
The thermostat is exposed to 90% hot coolant from the engine on one side and 10% cold coolant returning from
the radiator bottom hose on the other side.
Hot coolant from the engine passes from the by-pass pipe through four sensing holes in the flow valve into a tube
surrounding 90% of the thermostat sensitive area. Cold coolant returning from the radiator, cooled by the ambient
air, conducts through 10% of the thermostat sensitive area.
In cold ambient temperatures, the engine temperature is raised approximately 10 °C (50 °F) to compensate for the
heat loss of 10% exposure to the cold coolant returning from the radiator bottom hose.

Well mine certainly does not raise 10 degrees C in cold ambient temperatures! The manual is complex like the system. It says there are two thermostats in the text but in the system diagram and parts list there is only one. And when I look at the system flow diagram the bypass from the thermostat (Y shaped thingmy) goes back to the pump as you would expect, so why should the bypass make the thing stop heating up? I'm going to try keeping the revs really low next outing and see if that speeds up warm up time. How much is a new thermostat?

And the bypass description from the same manual...

By-pass flow valve
The by-pass flow valve is held closed by a light spring. It operates to further aid heater warm-up. When the main
valve is closed and the engine speed is below 1500 rev/min, the coolant pump does not produce sufficient flow
and pressure to open the valve. In this condition the valve prevents coolant circulating through the by-pass circuit
and forces the coolant through the heater matrix only. This provides a higher flow of warm coolant through the
heater matrix to improve passenger comfort in cold conditions.
When the engine speed increases above 1500 rev/min the coolant pump produces a greater flow and pressure
than the heater circuit can take. The pressure acts on the flow valve and overcomes the valve spring pressure,
opening the valve and limiting the pressure in the heater circuit. The valve modulates to provide maximum coolant
flow through the heater matrix and yet allowing excess coolant to flow into the by-pass circuit to provide the
engines cooling needs at higher engine rev/min.

This makes sense then. If you just get in your motor and drive it on the open road, you'll have to wait until the whole radiator circuit warms up before you get any juice out of your heater. Keep the revs way down low and it should heat up faster. Assuming the bypass valve, which I think is in the thermostat body (y shaped thingy), is working and not fooked!

ratty said:

I might get another thermostat and try that but the one thats in there is only 4 or 5 months old. As they have 2 valves I rekon that the bypass valve that operates at 1500rpm plus is the reason that it takes so long to even think about warming up.

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Or the heater matrix is clogged and therefore the bypass is always on.

I've got a multimeter with a thermocouple (£25 from maplins) so I could try testing the thermostat and particuarly the temperature of the bypass pipe during warm up as it should be cold when idling. Biggest issue is all the damn whirling bits all around it! Best tape up me wires during the test.

jzcktv said:

Just been reading the coolant section in the TD5 workshop manual from the RAVE I downloaded last night.

Thermostat - Main valve
The thermostat is used to maintain the coolant at the optimum temperature for efficient combustion and to aid
engine warm-up. The thermostat is closed at temperatures below approximately 82 °C (179 °F). When the coolant
temperature reaches approximately 82 °C the thermostat starts to open and is fully open at approximately 96 °C
(204 °F). In this condition the full flow of coolant is directed through the radiator.
The thermostat is exposed to 90% hot coolant from the engine on one side and 10% cold coolant returning from
the radiator bottom hose on the other side.
Hot coolant from the engine passes from the by-pass pipe through four sensing holes in the flow valve into a tube
surrounding 90% of the thermostat sensitive area. Cold coolant returning from the radiator, cooled by the ambient
air, conducts through 10% of the thermostat sensitive area.
In cold ambient temperatures, the engine temperature is raised approximately 10 °C (50 °F) to compensate for the
heat loss of 10% exposure to the cold coolant returning from the radiator bottom hose.

Well mine certainly does not raise 10 degrees C in cold ambient temperatures! The manual is complex like the system. It says there are two thermostats in the text but in the system diagram and parts list there is only one. And when I look at the system flow diagram the bypass from the thermostat (Y shaped thingmy) goes back to the pump as you would expect, so why should the bypass make the thing stop heating up? I'm going to try keeping the revs really low next outing and see if that speeds up warm up time. How much is a new thermostat?

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I got one last summer but I forget what it cost £30-£40 something like that. Looks like an aliens heart and 10 times more expensive than the 200 or 300tdi"s