Running temperature

Yeah flushed it until the water ran out clear. Didn't take much as I'd done that not long ago too.

Was your heater control set to hot or cold when you emptied it?

Col

I don't have a heater Col.

kermit_rr said:

Personally, I've never done that. I am very careful around the tank however and if i was that closer, I'd probably take it off for ease of access.
An empty tank has more fumes than a full tank, it's the fumes that go bang.
Not telling you what to do, just what I do.
In my opinion, it's more important to disconnect the battery

Click to expand...

The fumes may go bang but the spilled petrol is what makes for a horrendous fire. Actually, if there is nothing in the tank but petrol vapour it can't go bang as there is not enough oxygen.

We put a 160 degree “summer” thermostat in our 2.25 and after much idling on a warm day we only got 140 on the new gauge we installed. Has your original gauge always given reasonable readings before? Do you have an IR thermometer you could point at the block or thermostat housing? They can be handy for checks.

I don't know how the gauge has read before. This is the first time I've really been running it since I got it.

How does an IR thermometer work? Is the idea to measure the air temp very close to the block at various places? What temperature range is normal?

Reading the Haynes book last night it sounds like my drain tap might not be broken but just clogged up behind so I'll try clearing that today with something.

It's only taken 5L of coolant so far. I'm expecting to get another 3L or so into it which I'm hoping will help the running temperature some more. I couldn't get more into it yesterday after running it as removing the cap just boiled the water over, then I had to come in to work. If I can't find a way to get more than the 5L it's had into it I'll be back asking questions but I can't see it.?

I think it will take about 8L based on a youtube video I watched. But I don't have a heater.. so maybe 5L is about right for my 2.25 petrol with no heater. What do you think?

It's hard to say how much water a heater holds, probably not as much as 3 litres. I'd guess about a litre and half with its associated pipework, the matrix isn't all that big. If you've got 5 litres in, it shouldn't overheat all that quickly unless it's a very hot day. A fan does a lot of the cooling whilst driving along, I've never flushed mine, the coolant is a horrible colour but it takes about a mile of driving to get the guage into the normal range and so far it has never gone near the red, even when sitting in traffic on a very hot day.

Col

Well that went well. I unclogged the drain tap and then discovered the T-piece thread was ruined and so couldn't shut it off again. Thankfully the main plug thread was fine so I just need a new drain tap - could have been much worse. New one coming tomorrow from Turner Engineering. slowly slowly fixy landy.. but I'm getting there... !?

An IR thermometer works by measuring the heat (IR radiation) coming from an object. You would hold it about 6 inches away from the block or thermostat housing while pressing the trigger. Over here you can get reasonably cheap ones from hardware stores.

I may get one, Gord, but I think I may try a new temperature sender first. People on this thread are saying it takes some driving to get their gauge up to the N, but mine lifts and reads above N in under a second after turning the key so I am now wondering about the sender and/or my temp gauge..

If it does that immediately I agree that the sender or the gauge is bad. You might also trace the wiring to make sure it is intact. Can be suspect on these old vehicles.

Take the wire off the sender and make sure gauge stays showing cold with ignition on, if it does replace sender.
Gauge casing should be earthed as well as this can affect some types of gauges , usually a bunch of earth wires on clamp bolts holding gauges in place.

Fit an after market temp gauge that reads in degrees and know what the temp is, TIM and Durite two well known makes. Electric and capillari type available
Your gauge, sender, volts regulator and it's wiring are 35 years plus old.
Leave the original for show if you want,[ the one on my series 3 only just comes off the bottom when up to temp.]
Hang the new one on the dash below instruments.

New drain tap in today, refilled with coolant.. Started her up, gauge moved straight up to just above N.

Is the photo my temp sender? If I unplug that my COLD START light goes out, so I assume it is. Nothing happens to my temp gauge when I do that though..

that is not the temp sender but the otter switch for the choke light. the temp sender is on the other side of the head just under the thermostat housing.

If the guage goes up to or above norm immediately, there is summat wrong with the guage or wiring. There is a voltage regulator behind the dash, it is oblong and silver coloured, about 2 inches long. If that is faulty your temp and fuel guage will be unreliable. It is cheap to replace.

Col

I've fit a new temp sender and voltage stabiliser. The gauge seems to read very low now, it's barely lifted off cold when the thermostat opens at 72.

The last resort to get something useful for spotting an issue would seem to be trying to adjust the gauge's spring and bimetal tensioners. I've heard this is a bit voodoo, so I could send it to a pro and let them try..?

My ideal would be that it reads about N when the thermostat opens, raises a bit more with some driving - and if it gets near red it's telling me I should be getting worried.

Oh, and the gauge does sink down to read nothing if I unplug the sender. I haven't tried earthing the sender connection to see if the gauge reads max like it should, or just half-way up or something. But I think I've narrowed it down the gauge by now anyway..

I don't think mine goes much above cold, I've only seen it in the middle of the range on a few occasions when sat in traffic on hot days, so yours might not be far out now.

Col