HS6 Carburettor - Strip and Clean

While I was fixing the self cancelling indicators and the horn, I needed easier access to the steering column. So the carburettors had to come off. They were very dirty, so I'd decided that it was time to get the toothbrush and the Gunk out and give them a scrub.

Most of this entry is going to be made up of photos as there is very little to expain about the SU carburettor. It is a superb piece of British engineering with something relatively simple yet able to accurately supply a fuel / air mixture to the engine.

A before shot....

Removing them from the inlet manifold, and a view of the inlet - looks pretty clean up there to me.

The carbs are joined together with this bracket in the picture below - the bracket holds the accelerator linkage (the long horizontal rod) which through the quadrant changes a 'pull' motion on the rod to a downward motion on the shorter vertical rod which then twists the short horizontal rod to pull the carburettor throttles open.

This bracket is not the genuine Standard Triumph part, it is a 'next best thing' that is sold by the TR suppliers. The original is unavailable (I've tried) and was unavailable when a previous owner converted the car from Strombergs to SUs. The bracket does have to be converted by drilling holes low down to accept the throttle return springs and to put them under the required tension to ensure that they do indeed return - I had to do this modification when I bought the car as it was impossible to properly tune the carburettors without it. While the bracket was off the car, I took the opportunity to cut off the slotted piece that you see on the left. A previous owner had opened the slot up, and bent it out of the way, but it is of no use on this vehicle, so had to go.

The real bracket should look like this.

It looks simple enough, I don't know why no-one has remanufactured it.


Here are the dismantling and rebuilding photos.

Please feel free to comment on my blog by clicking on the "comments" link below.

Self Cancelling Indicators

When I first bought Tina, I wasn't sure if she had self cancelling indicators or not. Certainly if she did, then they didn't work. Turning the steering wheel with the car stationary, the engine off and listening carefully, I could just hear the sound of the indicators trying to cancel so I had to investigate further.

I removed the shroud  to see that the self cancelling system comprised of a pair of levers operated by a cam on the steering column. when the indicator is on, the cam pushes the lever to cancel it when the steering wheel is turned back.

You can just make out that the cam is not exactly in the middle of the two levers - it should be, the wheels are exactly in the straight ahead position.

At first, I tried to move the cam - expecting it to be a spring clip that is just wrapped around the column but it wouldn't move. I spoke to some friends who thought that it was either spot welded on, or there was a 'pip' in the clip that went into a hole in the column. If so, I needed another way of moving it.

I looked under the bonnet for the steering column and decided to see if there was just enough room to move it round a few splines to ensure that the cam came back to the centre of the two levers.

I made a make shift pointer out of a ball point pen and some masking tape to enable me to count the number of splines required to get the cam close to the centre of the levers.

















In my crude way, I found that I needed to move the column by 2 or 3 splines to get the cam in the correct position.

Disconnecting the steering column flexible coupling (using the jubilee clip method in the 'horns' post) there was just enough room to move it round 2 splines. No more, because there is a flat in the column to allow the clamping bolt to pass. But, this was just enough.

Now that the cam is in the centre of the two levers, it still wouldn't work - the next bit was actually simpler than I thought. the indicator stalk simply needed unscrewing, pushing further in towards the steering column and then tightening. The screws go through a slotted hole, so there was some movement.

Brilliant, that now works. So before putting it back together, I sprayed the shroud black and put another indicator sticker on it.

The indicator sticker that I bought from Moss was a large sticker which would not sit correctly on the curvature of the shroud. The best thing to do is to cut out the white indicator symbol and just stick that on - looks great!

Please feel free to comment on my blog by clicking on the "comments" link below.