Temperature Sender Woes

[awemawson]

I suspected that the temperature sender on my 4600 was defunct. I proved the wire from it back to the instrument. Then with a hot engine tried to measure the senders resistance to ground, but got a VERY high reading (100k ohms or so).

So I decided to remove it and test it in boiling water. More easily said than done. I could JUST get a finger on it. The breather fume pipe from the rocker box, and the stay that supports the cowl get in the way of my (admittedly rather large) hands. Eventually got a 17 mm socket on it and got it out.

Hot water test proved it faulty, so tried to refit while replacement on way. After MUCH faffing about managed to drop it >somewhere< round the fan belt / cowl / tombstone never to be seen again.

Luckily I had measured it as 0.666" o/d and 18 tpi which is 3/8 NPT. Even more luckily I actually had a 3/8 NPT blanking plug hiding amongst my BSP ones. Went to fit it and had an exact re-run - managed to drop it, and lost it totally. Something is swallowing these things

OK rummaged around in my box of pipe thread dies - excellent, actually have a 3/8 NPT die. So I turned a 7/8 brass hex bar down and made another temporary plug but left it rather extended, also I turned a reduced diameter on the nose to make location easier and this time got it screwed in and leakproof

Now to decide which is the right sender to order - Malpas and Agriline both list two type but give no details of the difference so I suppose its a phone call tomorrow to sort out which is right.

I need a beer

[awemawson]

Well I eventually got round to fitting the new sender. Original was a screw and nut terminal, new one was a 'faston' 1/4" spade. I took the precaution this time to thread a strong but thin wire through the hole in the faston, so if THIS one dropped at least I could recover it. Using a deep socket, with a bit of tape to keep it at the end it went in a treat as holding the long socket was just possible round the various obstructions that stopped me last time.

Need to get the tractor to do some work to warm it up enough to register. Drove round the ten acre field three times yesterday and still only got the engine up to 60 deg C (according to my IR thermometer) so the thermostat didn't even open.