Wednesday, 29 March 2017

25th March 2017, Rear Brake Cylinders and Daffodil Run

Not been too much to do on the car over the winter since its last outing on the Ludlow Tour but I decided it would be interesting to try the set of TR8 rear brake cylinders I had to see what difference they made.  The standard 5 speed TR7 cylinders are 0.7" (17.5mm) diameter and the TR8 ones are larger at 0.75" (19mm) and the effect of the larger cylinders is to increase the amount of rear wheel braking which seemed like a good idea.  I had read various opinions about the swap and thought it was worth a try.

Just for reference, the car already has Princess 4 pot calipers with vented discs on the front, an uprated servo/master cylinder and a Ted Schumacher modified pressure limiting valve.

The two types of cylinders look virtually the same but they have a roll pin used to locate in the backplate on opposite sides to prevent fitting the wrong ones accidentally. All that is required is to drill an additional 1/8" hole in the backplate on the other side and they are a straight swap.
I also took this opportunity to clean and lubricate the self-adjusting mechanisms with graphite powder but when I tried to refit the first brake drum it would not go on.  I checked the brake shoes were all fitted correctly and tried again but no good. After the third unsuccessful attempt of taking it all off and refitting I started to wonder what was going on. I double-checked the shoes and springs yet again but they were all correct so what was wrong?   At this point I decided to compare the dimensions of the cylinders in case that revealed something and this is when I found that the pistons on the new cylinder were not retracting fully. Taking it off (again!) I found that the small spring that fits between the two pistons had somehow got itself lodged across the cylinder instead of being in line and was preventing them going back properly.   This time it all flew back together and the drum went on easily. The other side was simple and gave no problems.

Next day I had to deliver some documents to Gloucester about 10 miles away and it was a nice day so a good chance to take the TR7 and try the new brakes.  They felt fine and all was well until a car in front made a right turn without indicating and I had to brake suddenly. This resulted in a lurid sideways moment, luckily with hitting the scenery or the oncoming traffic.  The rest of the journey was OK but I was very careful not to use the brakes too hard and the original TR7 cylinders went back on a few days later.

25th March.  Daffodil Run

Two days before I took the chance to pop over to my local rolling road at Maynard Engines to get the carbs and ignition settings checked. Some minor adjustments of the carbs got it running better and a final tweek of the ignition timing had it running better and smoother than ever.

 The Daffodil Run is a round of the HRCR Scenic Tour series and starts only about 20 miles from home at Birdwood.  It is a smaller event and is limited to only about 30 cars so I had got our entry in early to ensure a run.  The weather was perfect, cold but with clear blue skies so ideal for open top motoring and the organisers got the day going nicely with hot drinks and bacon rolls at the start.
Our TR7 in good company.
Good selection of cars at the start.

The route took us out through the lanes around the Newent area which is famous for its displays of daffodils at this time of year to a coffee stop at the Yew Tree Inn on the river bank at Chaceley.  Its quite well known for being cut off when the River Severn floods on a fairly regular basis.  Here they served us coffee with lovely home made cakes so it was a bit difficult to drag a ourselves away.
Jo enjoying her coffee and cake.
 The second half of the route went out around Redmarley, Much Marcle and Woolhope before finishing at the Three Shires Garden Centre near Newent.  Here they presented us with some bunches of daffodils and served us an excellent full carvery meal to round the day off nicely.
Daffodil Run souvenir

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