Hi all
I have now refitted my twincam which runs on fuel injection and need to house the original dual gauge bulb and an M12 temperature sensor to feed information to the ECU to match the mapping.
I started by locating the dual gauge bulb in its original position and used the tower adapter with the radiator cap on the top (from Burtons) because it has an M22 housing on the side and I fitted the ECU temp sensor into that.
Looked lovely and neat until we ran the engine and it dawned that it is on the wrong side of the thermostat which explained why the mapping didn’t seem to work.
So - I need to relocate the ECU temp sensor on the engine side of the thermostat ideally at the top of the head so that it can read properly.
The only solution I have come up with so far is to make a Tee adapter that takes both bulbs but that would take them out of the water flow in the head creating in effect a back water. I dont think this would be disastrous and with a week before the MOT which I dont want to move again, I thought I’d consult the hive mind to see whether anyone can suggest a better or different solution.
My fall back is to reverse the sensors for the time being so that the EFI sensor sits where the old bulb was and put the bulb on the other side of the thermostat. It wont read properly there but when the stat opens it will then do its thing as usual. Not ideal though.
So thoughts and ideas welcomed please
Many thanks
Gavin
Hi Gavin
Your fall back solution for the time being looks like a good temporary solution but the issue is a bit of a conundrum. How about using your ECU temp sensor not only for the ECU but also as a temp sensor by connecting it to a read out gauge of some sort?
I wondered about suggesting using your Tee piece with the heater valve port but that would not be an elegant solution.
Does anyone know if there are any blanking plugs in any of the head waterways which could be utilised?
Mike
Hi Mike
Yes I wondered if you can share sensor signals across the ECU and temp gauge. That would be the neatest solution by far.
I will ask Dave at Emerald and see what he thinks - he has been really helpful so far.
In the meantime, I fear that function might overrule form - whilst I agree that a tree of brass wont be pretty, it will give me the gauge and working ECU so this might have to do for the interim.
I have assumed that even if I take the bulbs from the sensor and gauge away from the water flow, the water surrounding them will heat up at pretty much the same rate as the flow so it shouldn’t be a complete disaster……
Cheers Gavin
Got a similar issue at the mo. Fitting FI to my +2. I have fitted a 3/8 bsp t peice to the heater take off line on the thermostat housing. You can just see one end of it in the photo.
On one end of the t peice I have put the heater connector. The other end i will be putting an M12 female 3/8 bsp male adapter to enable the temp sender.
Tim
I use a spacer to go between the head and the thermostat and mount the ECU sensor into the spacer. You may run into height problems as you are using the tower rad cap mounting. Other things can also cause problems, some bonnets and tall blocks etc.
Hello Gavin
Look here: TC cylinder head plugs - #7 by ElanDNA
I drilled the cylinder head before assembling it.
It still works today.
I can’t say whether it’s possible to drill it afterwards, it’s been too long since then.
Greetings Urs
Thanks Tim. Im working on a sprint and dont have to worry about the adjacent servo so will probably tee off the bulb sensor port.
Thanks Elanman - I think this is the route I will follow for the moment. I did a quick check with the Smiths dual gauge catalogue and didn’t see a non bulb alternative but will delve further
And thanks to Urs. Had I realised that I needed two sensors in one place while the engine was being rebuilt I would have followed suit. This caught me by surprise because the last time I ran this set up, I was using an electric water pump without the thermostat so it wasn’t a problem. Now I am changing from competition to road use, it completely slipped by….
Gav, If you need a DXF file of the shape etc let me know. As I said in my first post do check for bonnet clearance.
I gave up on the mechanical temp instruments due to them failing quite often, I fitted a CAN bus readout from the ECU. Works well but obviously not cheap.
Cheers
John.
How about tapping into the heater pipework from the head. It’s the right side of the thermostat and flows continuously.
Donels, for a +2 you are correct and it would work OK. But an Elan has a water flow controlled heater so not quite so good.
Cheers
John.