RETURN TO THE HILLS BECKONS
HWM-CHEVROLET
RUN BY Simon Taylor
OWNED SINCE July 2000
PREVIOUS REPORT June 2023
When the Stoveboltʼs engine was rebuilt last year by Rob Loaring at ICE Engineering, he found that its three downdraught carbs were worn and floppy. One wasnʼt even reaching full throttle. It was a job for a specialist, so over the winter sorting them was a priority.
There are lots of SU and Weber experts around, but they all shied away from twin-choke Rochesters of uncertain vintage. Then I found Ian Soanes at Coln Engineering in Gloucester. Heʼs a carburettor wizard, and his eyes lit up at the prospect of working on a type heʼd never handled before. First, he tracked down the correct rebuild kits to a rural corner of the USA. After their long, hard life my carbs proved to be full of bodges, leaks, incorrect screws and butchered threads, which had to be drilled and tapped before all the new bits went in. The bases were distorted and had to be milled flat.
Ian also machined new idle mixture screws, not included in the rebuild kit, and made up a neater throttle linkage so that all six barrels opened precisely together. Everything was done meticulously, and a month later I got back three perfect Rochesters.
The Stovebolt endured another punishing season in 2023, not so much on the (smooth) hills as on the (pothole-strewn) public roads. After looking after it for 14 years, Sean Mcclurg loves my old car and knows every inch of it. A driver himself, as well as a first-class engineer, he approaches each problem with a racerʼs eye. Every winter he gives it a good service and goes all round it tightening
everything thatʼs shaken loose, but this year there was more to do.
One of the transverse leaves of the front spring had broken near the end. They were custom-made in 1955 by Tom Carstens when the big V8 replaced the lighter Alta engine, so no off-the-shelf replacements existed. Sean sorted it by shortening, centring and redrilling that leaf. He dismantled the rear spring, too, and each leaf was derusted and soaked in oil. The rear wishbone bushes showed wear, so new ones were made.
Iʼd noted some backlash in the diff, which was a bit of a worry. Itʼs a Winters, and they cost £2500. Mine was fitted in 2005 after the previous, 50-year-old Halibrand finally disintegrated and, like its predecessor, itʼs a massive unit with the drive going under the crownwheel to turn quick-change gears at the back. Sean hauled it out and took it to his favourite transmission guy, Bill Mcdonough at Hardy Engineering based in Leatherhead. He checked it all, found the cogs were in good nick, and just had to replace the outputshaft bearings. Phew.
Motorsport UK only allows race seatbelts to last eight years, so we have had to replace my 2016 Willans harness. Also, Sean is tracing an elusive wiring problem that suddenly killed the engine on two fraught occasions last year – once when overtaking a line of traffic on the Oxford bypass.
A few more details to chase up, and when itʼs all together weʼll have a session on the rolling road, to set up the new carbs. Then the first Shelsley of 2024 beckons.