Joined: Jan 2019 Posts: 1,590 Threads: 21
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Location: Bala North Wales
Car type: 1933 RP Standard Saloon
Thank you Ruairidh, for your tip. I tried this and then tookthe car up Bwlch-yr-Eira on the B4391. The car climbed the steep bit in third all the way. Previously it required second for part of the climb. It then managed the rest of the pass in top at between 25 and 35 (depending on gradient) all the way to the crest, whereas, before parts of it required third. The little car seems to be going better than it has ever gone and so far no more clutch slip.
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Location: Scotchland
Great news - happy days ahead.
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Hi Folks,
Today I stripped down a fuel pump cleaned it all out fitted a new diaphragm after spending a while getting rid of the wear marks on the lever arm with an oilstone.
The body is marked 7 hp T Type pump.
This pump is destined to go onto a Nippy Engine which is partially assembled.
Joined: Mar 2015 Posts: 5,523 Threads: 231
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Location: Scotchland
My father’s Chummy, the last A7 he bought (circa 1970), came up to be with us a few years ago after he found driving it around Bristol too busy and not enjoyable.
I’ve not used it for some time and was delighted to see it starting pretty much instantly today. It’s the car I came home from the maternity ward, went each day to school, learned to drive and went on honeymoon in.
20 miles around the Cairngorms today was supreme, the sounds and smells of the car bring a lot of memories back to me.
Ian and Jen will use it up here in the summer, it’s serviced and ready for them.
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Location: Monmouthshire
If he gives up Sevens, I reckon Mr Dunford could have a career as a romantic novelist or a script writer. What a lovely story.
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13-04-2025, 10:56 PM
(This post was last modified: 13-04-2025, 11:07 PM by Charles P.)
Married my new 10 stud crankcase (a previous machining task) with the new, freshly part machined 10 stud block for the first time.
Mighty relieved to find that the 3/8" stud holes in the block fitted onto the new crankcase. There's not much room for error with the bigger 3/8 studs.
Next onto reverse spot face the block mounting holes to get a flat washer surface and continuing to machine the valve and tappet arrangement. No rushing though because there's little-to-no room for mistakes.
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Congratulations, Charles. A significant achievement! I take my hat off to you.
All the best,
Stuart
Joined: Jan 2019 Posts: 1,590 Threads: 21
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Location: Bala North Wales
Car type: 1933 RP Standard Saloon
Yesterday being Passion Sunday, I indulged in my passion and drove the Seven, Not far - just up to Llyen Celyn to see how the major dam reconstruction works were going and a separate trip over to visit friends at Llandderfel. about 20 miles covered in all.
Joined: May 2018 Posts: 2,169 Threads: 112
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Location: Llandrindod Wells
Car type: 29 Special, 30 RK, 28 C Cab
(13-04-2025, 10:56 PM)Charles P Wrote: Married my new 10 stud crankcase (a previous machining task) with the new, freshly part machined 10 stud block for the first time.
Mighty relieved to find that the 3/8" stud holes in the block fitted onto the new crankcase. There's not much room for error with the bigger 3/8 studs.
Next onto reverse spot face the block mounting holes to get a flat washer surface and continuing to machine the valve and tappet arrangement. No rushing though because there's little-to-no room for mistakes.
Wow. Fantastic engineering Charles. I guess you won’t be going into production  . But what would the costs be (your time alone would rack up a small fortune). At the end of the day into what is it going?
Cheers
Howard
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15-04-2025, 09:23 AM
(This post was last modified: 15-04-2025, 09:25 AM by Charles P.)
(15-04-2025, 08:40 AM)Howard Wright Wrote: (13-04-2025, 10:56 PM)Charles P Wrote: Married my new 10 stud crankcase (a previous machining task) with the new, freshly part machined 10 stud block for the first time.
Mighty relieved to find that the 3/8" stud holes in the block fitted onto the new crankcase. There's not much room for error with the bigger 3/8 studs.
Next onto reverse spot face the block mounting holes to get a flat washer surface and continuing to machine the valve and tappet arrangement. No rushing though because there's little-to-no room for mistakes.
Wow. Fantastic engineering Charles. I guess you won’t be going into production . But what would the costs be (your time alone would rack up a small fortune). At the end of the day into what is it going?
Cheers
Howard
Thanks Howard
The casting were made by Dave Flake and the patterns are now owned by a friendly member of the A7 Community. However the cost of castings in both ali and cast iron have risen noticeably making low volume runs hugely uneconomic. Add the fact that so few crankcases have ever been machined from the bare castings and you get an indication of the challenge/cost.
And the availability of very good newly cast CNC machined blocks (although not to the factory 10 stud Grasshopper design like this) makes this sort of block machining approach commercially unviable.
If I did count up the hours on this project, the number spent thinking and planning would exceed the number devoted to machining by at least five to one. But I haven't counted the hours, so we don't have to worry. I'm a largely self taught amateur so take much longer to do this stuff than a real machinist would, so any estimates of my time would be pointless.
The end plan is to put it in my car and hillclimb it. Utterly pointless since the advantages it brings, if any, will be vanishingly small. Pigsty have proved that you don't need the factory 10 stud engine to go very fast.
It's a Mallory and Irvine exercise; "because it's there". And I always fancied a 10 stud blown engine.
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