EGT Probe failure

[Mag]

Had a stage 6 EGT for a few years and it was great for setting up the jetting, but the probe failed last year and I didn't get round to replacing the probe till december. Ordered it from SIP but was on back order not turning up till last month, which was ok as I didn't replace my exhaust till last week.

So I drill a hole in my brand new Franspeed Race and start checking the jetting. Gauge works fine and I soon see its reading a little hotter than my Rev Tour but that could be the position of the probe or a variation in the probe itself and in 40 miles...its stopped working!

[coaster]

Does the SIP gauge need power to it? My analogue one does and whenever it has stopped working it has nearly always Ben due to loss of power. I had a couple of VHS probes fail when I first got it but the last one direct from China had a right angle entry and has been fine for over a year now.

[Mag]

It's got power, after showing irratic temperatures it displays a line of dashes. Same as when the last one failed but that was after 1000s of miles

[wack 63]

Coaster, I got one of the 90* ones from China but it reads far lower than the Airworld one so wonder if it isn't compatable with the Falcon gauge? What gauge do you have ?

[Adam_Winstone]

Mine in my Fran Supertourer reads considerably cooler than in my earlier JLs, which is probably down to the fact that I've had to move it slightly further away from the exhaust port so that it is central to the stronger/longer section on pipe, rather than close to the welded bends.

[coaster]

Coaster, I got one of the 90* ones from China but it reads far lower than the Airworld one so wonder if it isn't compatable with the Falcon gauge? What gauge do you have ?

I'm using one of these http://www.skydrive.co.uk/proddetail.asp?prod=EG001 and it reads about the same as the straight one that it replaced. the depth that the probe is inserted makes a difference mind.

[wack 63]

Thanks, that's the same as I have. I always set the probe tip to sit in the centre of the header so can't see why it would read different although I tested it first with a propane torch but it seemed slow to react compared to the straight probe.

[coaster]

Thanks, that's the same as I have. I always set the probe tip to sit in the centre of the header so can't see why it would read different although I tested it first with a propane torch but it seemed slow to react compared to the straight probe.

Luck of the draw as far as quality control goes I guess It's the technology as for the CHT probes, 2 dissimilar metal wires (I forget what type) which when twisted together and heated, generate a voltage proportionate to the heat applied. On the CHT the twisted wires are crimped into the spark plug ring and with the EHT variety the twisted wires are inside the probe tube. I imagine there is plenty of room for error in the production stage which would only be picked up in decent quality control.