1983 110 Stage II V8 indicating an overheating issue

kermit_rr said:

You can always disconnect the heater and use a bit of hose to connect the engine feeds. If the hose gets hot then you know you've got flow and it's either the pipes to or from the matrix, or the matrix itself

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That's pretty much how it was configured before I put them back to how they should be. In effect, there was only really one pipe going to the heater matrix and the other was 'T'd' into with 90 Deg bend, thin walled plastic pipes. Very restrictive and the pipes hardly got hot. They both do now, which explains the 'heat' from the heater vents.

I'm not ruling it out, it's a possible explanation for the lack of heat but can it be used to explain why then engine indicates it's overheating?

I don't really want to change the gauges for non standard looking ones, it's quite an oddity and the after market gauge that was in there looked SO out of place.

I'll try to find out what the sensor should be outputting to the gauge....Anyone know where to look? Please don't say 'The internet'

kermit_rr said:

To check the sender is doing what it should, you can hear it up in a pan, the resistance should change smoothly across a reasonable range, i forget the usual numbers

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I'm fairly convinced it's the sender/Gauge combo.
It's NOT overheating but is only indicating an overheating issue.

If the sender was not immersed in the coolant and instead was in an air pocket, would it register a high or low reading on the gauge?
If high, then I'm looking at an airlock OR a sender/gauge issue.
If low then it's not that because of my high reading.

I'm now on the hunt for some figures for measuing the sender. Does anyone know where these may be found?

Sender & gauge need to be a matched pair.
If they're not you're just wasting your time.
I'd suggest you speak to the suppliers of your gauge & buy a sender from them that they state is compatible with the gauge they sold you.

Ratae said:

Sender & gauge need to be a matched pair.
If they're not you're just wasting your time.
I'd suggest you speak to the suppliers of your gauge & buy a sender from them that they state is compatible with the gauge they sold you.

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Right, that's plan number one. The sensor is relatively cheap so I'll get that ordered tomorrow and see what happens.

The best way of measuring engine temperature is with a capillary gauge, and IME, the best ones are made by Durite, who also have good tech support; Viz:-

www.ebay.co.uk/itm/322993477122

Whether you leave it fitted, or put it "out of sight" ( if so inclined ) is up to you ......

I've measured the temperature in a number of places and it's reading pretty much where it should be, taking into account a tempeature loss through the material used at each point.
I could use an 8 way thermocouple connected to a 100Hz data logger from work but I don't think I'd read a wildly different set of temperatures in the same places internally.
Fitting the gauge to test is fine but I think I've done that, in a way. Fitting it for keeps is out because I'd like to keep this old V8 as standard as I can.

I've got the number of the place I bought the gauge from so I'll be calling to order the sender from them, rather than wherever I bought the last one from.
If that's still not right then I WILL be getting the professional measuring equipment out.

I once got brought a triumph spitfire with supposed over heating problems ..... the "garage" has replaced all sorts - the viscous coupling, the radiator, the hoses and all sorts .... I stuck a capillary gauge in, gave it some beans ... and the gauge never showed anything abnormal .... Then I measured the resistance of the sender with my fathers AVO Minor - it was fecked .... new sender fitted and the owner was happy with what I had done ..... with the "garage" ...mmm... significantly less so

Ok, I'm not going to say anything just yet but....I think I may have the wrong sender, maybe!
I need to do a little more digging on the various websites to confirm.

Well it looks like Ihav epreviously been supllied the oncorrect sensor.
Now there's no point pointing and blaming but I'll say that one supplier has been very helpful and genuinely intersted in chassis and engine numbers to supply the corrct part. The other supplier, delivered late, and have seemingly supplied the wrong sender.

IF this turns out to be the case then that's great and I'll sing the praises of the helpful company and I'll contact the other company to explain the differences between good and bad customer experiences.

at least you've got there and know what the issue was!

Christ I hope it's that simple....and cheap!

You can call me Nev

parptoot said:

Well it looks like I have previously been supllied the incorrect sensor.
Now there's no point pointing and blaming but I'll say that one supplier has been very helpful and genuinely intersted in chassis and engine numbers to supply the corrct part. The other supplier, delivered late, and have seemingly supplied the wrong sender.

IF this turns out to be the case then that's great and I'll sing the praises of the helpful company and I'll contact the other company to explain the differences between good and bad customer experiences.

Click to expand...

The new sensor arrived and was fitted last night. Not before I did a little pre-fit test with a cup of hot water to make sure it functioned.
Once in and up to temperture, the guage sat at just below the mid-way point and didn't budge, PERFECT!

The company that I bought the gauge from and this newer sensor was Famous Four. They have been genuinely interested and have asked me to call them back, once fitted, to let them know the results. I'll do that today.

The company that supplied the incorrect sensor was one of the big ones. I'll be calling to tell them what went wrong.

Anyhoo, it's fixed!!
I do still need to sort the heater but I'm hoping that's the matrix that just needs a better flushing or replacing.
Thanks for all the advice

Great news! It's always good to hear a positive outcome