• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Speedo assembly

Share this page

B

bob hughes

Luke Skywalker
Country flag
Offline
Hi Guys

Finally got around to making the new trip meter reset pin as a spare could not be sourced from anywhere over this side of the pond ( plenty of offers to recondition the unit though).

I am now stuck as to where the new rubber seal goes in relation to the bezel, glass, glass holder, casing assembly. When I dismantled the unit in the first instance, there were no rubber seals present just a hard mastic, so I ordered some from AH Spares. Two seals came - one a round section - and the other a square section. I believe that the round section fits over the casing to sit against the dash board and that the square section is the seal for the bezel/glass. I have tried it directly under the bezel - the assembly is tight, but the glass is loose. I have tried assembling the bezel, the glass and the glass holder face down on the desk and inserting the square section under the bezel lugs - a tight squeeze but it holds everything together, however trying to fit that onto the rear casing is a nigh on impossible.

I have discussed it with AH Spares and a Restorer but all to no avail.

Any ideas please?
 
Need to know what AH you have??
 
My BN4 speedo has a hollow rubber tube about 320mm long and ~3.5mm diameter which curls around inside the triangle shape of the bezel and presses on the glass once the bezel is installed. All four gauges are done this way.

Assembly is a matter of putting the black inner bezel in, glass in, rubber tube fits inside the chrome bezel and then it goes on with a slight turn to lock the little tabs.

I'm also in need of a speedo reset shaft/knob if you are in the mood to make another one

Andy.
 
Hi Guys

My car is a BJ7,

Andy, that tube idea sounds good, not sure if it is totally correct, but if it works then so what.I was getting around to something like that and was going to use super glue to fix the ends together.

Regarding making another, this one did not come out spot on, nearly there but drilling that 50thou hole through a 0.117 shaft - twice, is not an easy thing. On the advice of a model train maker I got a block of aluminium and using a friend's pillar drill and a fixed vice I drilled the required holes through it at right angles to make a jig. However the vice was not stable on the plate despite being bolted down so will be having a go again. The holes were a tad out for the split pin to go through so I have cut a leg off for now. Once I get a new jig made I will make a couple. There is a three line whip out in the house at the moment to get other jobs done so it will be some time I am afraid but I have noted it down and will contact you when one is available if you can wait.

Bob
 
Hi Bob,

Thanks for the offer. I won't be needing mine for a few more years yet so all good.

re the rubber tube- I'd be 99% sure my car has never been apart before so there is a pretty good chance the rubber tube is original. I had another look today and there are two rubber tubes, the other one goes in between the glass and the black inner bezel. If you can't find rubber then electrical heat-shrink tubing would be approximately the same sponginess.

Outer bezel upside-down on the speedo showing the two rubber tubes.
DSC07349.JPG


Andy.
 
Thanks Andy

It all makes sense to me, there is a slight indent in the black 'glass holder' that is made for a seal behind the glass. The rubbers supplied do not work in either position. I am on the case with a firm that supplies neoprene rubber at 4.5 mm OD so will give that a try for the front seal, the rear seal could be heat shrink as you suggest, or break into the supplied O ring and add a section in with super glue to make it fit the recess.( I have bought several - one for the rev counter as well)

Re the spindle - I think that I can meet your dead line :crazy: , I will advise when all is ready, it will be in brass - nice, and I will even throw in the two split pins as I had to corner the market to buy them.

:cheers:

Bob
 
Bob Hughes said:
Hi Guys



Regarding making another, this one did not come out spot on, nearly there but drilling that 50thou hole through a 0.117 shaft - twice, is not an easy thing. On the advice of a model train maker I got a block of aluminium and using a friend's pillar drill and a fixed vice I drilled the required holes through it at right angles to make a jig. However the vice was not stable on the plate despite being bolted down so will be having a go again. The holes were a tad out for the split pin to go through so I have cut a leg off for now. Once I get a new jig made I will make a couple. There is a three line whip out in the house at the moment to get other jobs done so it will be some time I am afraid but I have noted it down and will contact you when one is available if you can wait.

Bob
Click to expand...

Bob, re the drilling of the tube, you might like to consider investigating the local jewellers for someone who could draw you a tube to the size you need. At the very least they can draw a tube down which will have a (too small) hole running centrally through which you could more easily drill out?

regards
Simon
 
Simon

I think that you have the wrong idea in mind, the shaft is solid at 0.117 inch dia. with two 50 thou holes drilled through it at right angles, one to take the pin that keeps the sprocket in place and the other is at the bottom on the outside of the speedo to take the pin keeping the turn button in place. The centre of the 50 thou holes should be bang on the centre of the shaft, currently my best effort is in the order of 20 thou out, but I can get half a pin in so it does work.

:cheers:

Bob
 
Hi guys

Just an update on the seals for the speedo, I have been up and down the country buying tubing from manufacturers, and auto electrical shops, however, none seemed to work in whatever combination I tried :wall:.

I was down at my local fishing tackle shop taking my fly rod for a bottom guide replacement and I noticed that they sold rubber tubing for carp and sea fishing, something to do with making up rigs, so I bought some lengths of 2mm neoprene and silicone tubes and tried them today - spot on, :banana: if I was perfectly honest, the tube under the bezel could be a tad thicker - 3mm possibly but everything is rock solid. Put the joints at the top of the speedo just incase I get caught in the rain with the hood down :laugh:.

:cheers:

Bob
 
Shouldn't you have put the joint at the bottom....unless you are talking real deep water? Always nice to get tips like this. Is the neoprene black, not that it would show.
 
Tahoe

I figured that any water would run down to the where the seal is 100% intact, but I see where you are coming from. Let's be fair, I doubt that the glass on the speedo will get even a tinsy winsy drop of water on it.

The seal under the glass was black, but the seal under the bezel was blue.

:cheers:

Bob
 
Back
Top