It was a choice of about £100 for a set of UK clocks or 10p for a 20K resistor, so not much of a choice really. Anyway as I have all the soldering gear and used to solder stuff all the time, I wasn't worried about that bit.

 

Dismantling the dash board was interesting as I hadn't realised quite how much needed to come out, but apart it came in order to get to the screws holding in the bottom of the clocks.

 

So clocks out and on the kitchen table, I had to dismantle it to get to the PCB, carefully of course as it's a delicate looking piece of kit. Now I could see the resistor (33K on the Jap Spec clock) right next to a chip on the PCB. Getting the resistor out was straight forward, getting the new 20K one in was very fiddly as the solder sucker I used just couldn't clean the holes very well, but in the end the holes were cleared, new resistor placed in and soldered in place.

 

It was just a matter of putting everything back together and going for a run, hey presto clock reading much lower and looked about right. The next job is to compare the speedo against my GPS and calibrate it if necessary and whilst I had the clocks out I made a couple of small holes above the 2 POTS on the PCB so I can get a small screwdriver in there very easily to adjust if necessary.

 

Not a bad saving for a few hours work.

 

Oh and I have some spare resistors if anyone wants one.

 

Gaz

Good work. The really tricky part is adjusting the speedo whilst you're driving ! ;)

Good work. The really tricky part is adjusting the speedo whilst you're driving ! ;)

 

I think it'll be easier with the roof off as I can stand so I can see the POT properly :D

There are two Pots at the top of the PCB, does anyone have a link or know how each one is used to adjust the speedo. I'm only about 12% out but I may as well get it as close as possible whilst I'm doing it.

 

Cheers folks,

 

Gaz

 

 

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Don't know how to post a link to another thread!, but search for a thread 'Converting J-Spec clocks to read US dials' post number 13.

Don't know how to post a link to another thread!, but search for a thread 'Converting J-Spec clocks to read US dials' post number 13.

 

Excellent, found it and it also explains why the 'bong' started when I adjusted one of them. So at least I know which one to fiddle with now, although it doesn't make adjusting on the move any easier.

 

Gaz