Good morning, all, especially Greg in France who has been helping me with the speedo transducer issue in my car (1987 XJ-S V-12 VIN 135xxx). After much fooling around and testing, I decided to purchase a new transducer. When I attempted to install this new unit today, I found that the mounting portion is too small to fit onto the speedo drive gear housing! The unit on the car (original, who knows??) has a 27mm nut for attaching to the housing, while the new replacement unit (Eurospare UK DAC 4569) has a 22mm nut, so "no way Jose". Does anyone have any thoughts on this situation? I have sent an email with pictures to the vendor, I am still well inside the return window if needed. My current thinking is that possibly the drive gear housing on the car is incorrect? There seems to be a changeover in housings above 39 tooth (40 tooth starts a different housing). I am attaching a couple of pictures to help with analysis... Interestingly, the drive spindle is LARGER on the new unit, and for whatever reason, the drive spindle on the unit I am replacing looks beat up.
All thoughts and comments from my Guru friends most appreciated!!
Warm regards,
John

Original unit, spindle kinda beat up

New unit (left) has beefier spindle


Original has larger nut, on left

Original on left.

 

I’m pretty sure the the small nut version is used on the Series 3 XJ6 with the BW66 trans

Cheers
DD

 

Thanks, Doug!
I also saw a picture of a DAC 4570, which looks to have the smaller nut (hard to tell in pictures), which was listed as XJ6 series III, and XJS to VIN 113536. I have a strong suspicion that this is what they sent, although in a bag marked DAC 4569....
John

 

I think the small nut is DAC4570. All the photos I've googled of DAC4569 show a large nut, and DAC4570 seems to be a small nut version for S3 cars.

Paul

 

Correct; I think you have been sold the wrong part John.

 

I bought this from Welsh for my 87 XJ-S, it fit perfectly and the speedo reads accurately now.

#TES-1800-262 XJS Speedometer Transducer



Old and New


Transmission fitting


New part installed



HTH, Dave

 

Hello, everyone, just an update... I purchased as new speedo transducer from Welch at the suggestion of Dave Allen (thanks for the tip, I had never used them before). The new part showed up and was a perfect match for what I had in the car (same as pics posted by Dave above). I installed the unit a week ago, but only finally got to test-drive it today. I am happy to report that it seems to be working perfectly. I only drove about 50 miles, so more time is needed for a "full endorsement".
One thing I noticed immediately was that the speedo "came alive" right away, at very low speeds. The bad transducer only kicked on the speedo at about 20mph, and only then would the speedometer spring to life. Other symptoms of the bad transducer was speedo only working if the car was cold, speedo only working at all for short distances (3-20 miles) before dropping stone cold dead. Interestingly, while trying to resolve this issue working with GREG from France, the transducer worked fine while operated with a drill while wired in under the car! I "drove" the car for better than 30 miles at speeds from 60-80mph, and it seemed to work fine. Connect it back to the transmission, however, and the symptoms would reappear... I mention all of this for anyone researching similar issues with their car.
In any event, thanks to all for the help, most especially Greg in France who has spent a LOT of time working on this issue with me....
On to the next item!!
Thanks again,
John