[Speedometer problem after installation of d type overdrive]

So… having said I will wait until after my Le Mans trip… I have made some progress. I ground a few mm off the cable at the gearbox end and having checked a “spare speedometer” on the bench also removed a couple of mm from the speedo end. The good news is that the spare unit seems to work correctly (although my be slightly off in speed) when it it just dangling in the car and not fitted… that’s the next job. But before I do I need to remove the bezel and clean the glass on both sides. 
the bezel has already been attacked in a previous life and could do with a replacement. 
 

so does anyone know where I can get a replacement bezel at reasonable cost? 

[Speedometer problem after installation of d type overdrive]

Thanks for the detailed description. Very useful 😀👍

[Speedometer problem after installation of d type overdrive]

Will do thanks…. Going to wait until return from Le Mans classic at end of month for fear of breaking it before the trip!!! 

[Speedometer problem after installation of d type overdrive]

Thanks again... Yes it has the angle drive and yes it has the washer fitted... I think I will remove the speedo and 'fettle' with it out of the dash.

 

[Speedometer problem after installation of d type overdrive]

Thanks Pete. Do you happen to know (or know where I can find details of) what length of inner cable is needed to engage properly  and what maximum length can be so as to avoid Interference.

[Speedometer problem after installation of d type overdrive]

Hi all , 

My speedometer failed soon after the installation of a d type overdrive to my 1967 Herald convertible. 

The speedo was professionally overhauled about a year ago and had been working fine before the overdrive installation.

First symptom after just a couple of miles was that the speedo needle refused to settle below 20 mph. Then the speedo stopped working altogether. 

I released the cable at the speedo end and the needle dropped back to zero whereupon I reinserted the cable and tried again... the speedo didn't register any speed, although the odometer is registering.

I have since installed a new cable (having been advised that the original had too much core showing). 

The Speedo now only works if the cable is backed off a bit and now (with it backed off)...

I have a situation where the Odometer reads correctly but the speedometer (albeit steady) over reads by approx 10 mph up to 35 mph and then 15-20 mph between 40 and 55 (as measured against a phone based gps app).

The fact that the odometer is plumb bob on would indicate the correct TPM and that the cable is turning correctly?

I am a bit confused... Might I have damaged something inside the speedo head? 

I would be interested in your collective views/ experience in respect of diagnosis and possible prescription to fix..

 

[Propshaft measurement and adjustment]

Thanks for all of the replies. I have thoroughly inspected and measured today and all is well no play at all. 
No means of adding grease to one of the uj’s so guessing it is a sealed for life bearing. 
 

splines all good and no sign of wear or play. 
 

accurate measurement is 47” which is correct. However this is the measurement with the slider at shortest length. Still a bit concerned about how to deal with the length if indeed it is 46 1/2 “ that is needed. 

[Propshaft measurement and adjustment]

I will have a fiddle tomorrow 👍thanks for the suggestions

[Propshaft measurement and adjustment]

I have test to fiddle with the adjustment and have not inspected the splines. Overall the condition seems better than I was expecting. 

[Propshaft measurement and adjustment]

Hi again all,

Just to recap…plan is to fit a three rail spitfire box with d type overdrive.
I recently tried to purchase a new propshaft (vitesse non overdrive 47”) that stated it was good for herald overdrive conversion but vendor had just sold out. He said that he had a secondhand one available so I Purchased that. It has arrived and measures 48 1/2” with what looks like about max 1 1/4 “ of adjustment in it to shorten. Is it normal to measure from flange to flange? Or some other way. Have I purchased a dud? My understanding is that length needed is 46 1/2”.

I am trying to assemble everything I need in advance and now a bit unsure. 
thanks

david

[How best to flush out a gearbox/ overdrive]

Thanks for the info. It was sold as a working concern so I think I will fit a new end seal on the overdrive and a couple of new gaskets and fill up with oil. 👍👍😀

[How best to flush out a gearbox/ overdrive]

I am making progress with my three rail d type overdrive that will go into my Herald 1200. 

I have drained out the old oil and it looked reasonably clean with no nasties in it. The magnetic sump plug had scavenged just a very few bits of fine metal adhering to the magnet.
 

I have removed the overdrive filter and cleaned both it and the magnetic rings. It did have small amount of grey sludge no sign of black clutch material so I am guessing not significant and nothing untoward. 

so… my question is do I need to flush both through with either duck oil or paraffin or similar? To be belt and braces, Or just refill with EP90 when the time comes? 
 

[Adjusting solenoid in d type overdrive and not reverse selection]

12 hours ago, Peter Truman said:

Here's our 3 Rail Gear lever fitted to my daughters Mk2 Spit with the later single rail internals fitted into a 3 Rail case with J type overdrive.

The daughter wants the std Triumph O/D switch in the lever so my mods at the top currently I've drilled 3in down the center of the shaft, dead center? I want to go another 1.5inchs so a longer drill reqd, 

Please Tip Dave can you advise what length the hole is for the wires down the gear stick?

PT

Yes the wire comes out 10cm from the collar that the gear knob attached to. 😀

[Adjusting solenoid in d type overdrive and not reverse selection]

Would someone care to check my thinking…

diagnosis… the gear stick provided with the box is not correct. It has a spring mechanism to lift to reverse rather than press. And should not be part of this set up. 

prescription… I am thinking that I should be able to take the gear lever (only)  from my original herald three synchro box gearbox and substitute it for the wrong ‘un.

Is my diagnosis  right?  
will prescription work? 
 

I am not interested in having the overdrive switch on the gear lever and plan to use a column mount switch. 
 

ince again thanks for help so far 😀👍
 

[Adjusting solenoid in d type overdrive and not reverse selection]

Also, is this metal ring correct on the middle rail? 

[Adjusting solenoid in d type overdrive and not reverse selection]

1 hour ago, thescrapman said:

Also note if you put a 3-synchro top cover on a 4-synchro box you lose reverse engagement.

Is there any easy way to identify? 
that spoils my next plan which was to make use of my existing 1200 gearbox top cover. Maybe this is what has been done there … the current gear stick definitely isn’t right. 

[Adjusting solenoid in d type overdrive and not reverse selection]

Thanks for the suggestions… something not quite right! 
Unfortunately I have to work! Would rather be at home fettling 😀👍

[Adjusting solenoid in d type overdrive and not reverse selection]

Also, is this metal ring correct on the middle rail? 

[Adjusting solenoid in d type overdrive and not reverse selection]

Thanks for the info… with the gearstick removed I can move the third rail and engage reverse in position as described. However with the gear stick on I cannot move the lever far enough to the left. Does this mean I must adjust the lever that acts on the gear selection rails via the shift rod? 

[Adjusting solenoid in d type overdrive and not reverse selection]

Ah… the schematic in the gear knob ( with overdrive switch) shows it left of second!) doh 

[Adjusting solenoid in d type overdrive and not reverse selection]

Hi All

I now have a three rail spitfire gearbox stamped with FH number and a d type overdrive that I want to fit to my 1200 herald. The unit has been stood for many years. The solenoid plunger was sticking and found to be lightly corroded. It is now free and clean and operating with a 1.1amp maintaining current. With the inspection cover off the hole in the brass lever exactly aligns with the driled hole in the casing when energised but when released the lever moves back to the right but not as far as it could do. Is this because there is no oil pressure while testing on the bench? Is there any other adjustment? 

As a secondary issue, I am happy that all forward gears engaging smoothly with no undue play or noise… but for the life of me I cannot engage reverse. Is there a knack or adjustment? It looks like it should be a lift and movement to left of second gear. Any help as ever greatfully received. 😀👍

[1200 overdrive conversion]

I may have sourced a suitable candidate box to start the conversion process… can anyone help to diagnose the following numbers that are stamped on the candidate… 

-FC 67790 this is stamped, the following are in the casting--303546---N295---303709R,

thanks in anticipation 

david

[1200 overdrive conversion]

Is there any reason that I should not use a spitfire 1500 gearbox with j type overdrive. I think it has the switch gear in the gear knob. 

Thanks David

[1200 overdrive conversion]

As a bit of an aside… I have now received my October copy of the Courier and have read Colin’s most excellent article on  installing an overdrive … I do like these little synchronicities in life. Just as I start to ponder a way forward… within a week a most useful article plops through my letterbox. So… thanks for that 👍👍👍😀😀

[1200 overdrive conversion]

Thanks for all of the answers. I think that I will try to piece together all of the components… I am not in a rush. 👍