2 probs, exploding temp sender & broke new speedo cable!!

[relick62au]

Bugger, my box of goodies arrived from Paddock spares in the UK. They wanted to charge me 65 pound for freight so I got smart, they sent it to a rellie in the UK for free and I had him post it to me. Well, to post an 8 kilo package from here to the UK surface mail costs about $80 so I figured it would be about the same. WRONG, UK post was 85 pound surface and 95 pound air, so my rellie said oh well, we'll send it by air, cost me an extra $70 on what paddocks price was, BUT, I digress.
Whacked in the new speedo cable to the 2a, had to remove the retainer plate from the end of the old cable and put a slot in it to get it onto the new cable but that was fine, also put in the new temp sender, went for a little drive around the fence line (10min), the temp sender actually exploded, blew the top clean out and 10 metres into the air (no bonnet) with a few red hot bits to boot into the cabin (no roof). Then the speedo stopped working!!!
Has anyone had any thing similar with a temp sender, the wire to it has 12 volts to it, is this usual??
The speedo cable, there must be a problem at either the gearbox end or the speedo, any thoughts would be appreciated but preferably not ones that involve gearbox removal........
Russell.:o

[Aaron IIA]

Whacked in the new speedo cable to the 2a, had to remove the retainer plate from the end of the old cable and put a slot in it to get it onto the new cable but that was fine,


Why did you have to cut a slot into the retainer plate?

Aaron.

[JohnR]

The Temp sender ???? Realy weird! I would think you are running a Bi-metal gauge which should have a 10v regulator in line to the power of the gauge? If so you can get these here in Australia (Brisy) :angel: I can't say where that would be advertising :p

As for the speedo. Unscrew the cable from the back of the speedo and let it sit near your knees. Go for a short drive and with one hand try to hold the end of the cable inner. It should spin out of your fingers. If not you either have a cable problem or no drive from the gear box. I am interested in what you were saying about having to adapt the cable to the new speedo???? Sounds wrong. Maybe send photo's

The other test you can do is get a small screwdriver and try and turn the input shaft to the speedo if you can spin it the needle should just rise to about 5mph ish.

I hope this helps,

[relick62au]

OK, First the guage, it is the standard Landrover item, first thing I did was replace the guage itself (although with a used item which I could not vouch for), no result there so replaced the original sender unit with the Paddock Spares replacement and POW. I have never heard of a sender unit doing this!! I only tested the voltage on the wire with a test lamp (the multi meter was flat) but it came up with a good glow so I reckon it was around 12v. I thought maybe I had connected the wrong wire to the sender but it was the only one in the vicinity and it was the one that was connected to the old sender.
As for the speedo, it was not working so checked the cable and, as usual, it was broken off at the gearbox end with the squared off end of the inner cable still in the drive in the side of the gearbox. When the new one arrived I put it in went for a SLOW drive where the speedo wavered around the bottom mark (10mph) then just stopped. Pulled it off at the speedo end and could turn the inner cable, dis-connected the other end and it was broken off just like the original.
As for modifying the retaining plate (holds the gearbox end in place by means of 3 screws), there was not one on the new cable so pulled the end out of the old one to get it off and then slotted it to get it on the new cable. I cannot imagine the guage end would be able to create enough drag to break the cable so something is going on at the gearbox end.

Russell.

[JDNSW]

The temperature gauge on the 2a is supplied via a voltage stabiliser. This will give an intermittent output, so if you got a steady glow from your test light, it is either not in the circuit or is faulty (usually actually just the earth connection, not the device itself!). A fault would not not in itself cause the problem you encountered, but what could, is a wiring problem that puts 12v on the wire without the resistance of the gauge, so I'm guessing this is the problem.

Visualising the setup at the gearbox, it is difficult to see anything that could be wrong that could possibly break the cable - the only thing that could would be gross misalignment - so the question has to be asked, would the slot you cut allow this? More likely is that the speedo head is providing a high load - this is easily tested by filing a suitable nail to the same square as the cable, put it in the back of the speedo and it should spin freely between the fingers. There should be no appreciable resistance at all. If there is, the speedo is fairly easy to disassemble and lubricate - the problem is usually the grease on the input spindle gone hard. It may be feasible to squirt in from the back WD-40 or similar without disassembly.

John

[relick62au]

Thanks John,

I'll dig out the file and fire up the multi meter and check exactly what that voltage is but you sound like you are right on the money.

I love this site!!

Almost as much as I love my Landy!!:D

[JDNSW]

Another possibility on the speedo cable - unlikely, but you haven't go too sharp a bend in it have you? And you did grease the inner cable before installing it?

John

[relick62au]

Thanks again John,

So far u are on 1 winner. Dis-assembled the speedo this morning, it is locked up tight, hence the broken new cable. The drive area is currently soaking in a penetrating solution, I'll give it half a day and try it again. Have not got the meter on the sender unit yet, domestic duties are apparently more important than fixing Landrovers........