Does anyone know where i can obtain some piston rings for a Birmingham Scott engine – my pistons both have three rings, each held in position with a small pin in the groove ?
Any help appreciated,
Try Phil Daintree, 22 Hawkstone Rd., Whitfield, Manchester, N45 7PJ. Ph 0161 766 4487.
I have a reasonable selection of genuine Scott rings, what size do you need ?
Many thanks for the replies, the ring sizes i’m after are:
Bore diameter 73mm approx
ring thickness 1/16 inch
ring depth 0.11 inch approx
Three rings in each piston.
The rings I have are for various oversizes ie +.040. What oversize do you require as I do have a limited number in various sizes.Incidentally my advice would be to only fit the 2 top rings per piston the third one is somewhat superfluous and adds appreciably to the friction.
The three-ring piston was really only ‘listed’ for the 1939 Clubman Special, but no doubt stocks remained for years afterwards, and would be used as and when later pistons were out of stock, like when Hepolite’s bill had not been paid…..I am not really being cynical, but that is the way things often were.
By way of illustration, when Matt Holder bought the remains of the Shipley company in 1950, creditors came out of the woodwork wringing their hands like Uriah Heep, and the Fellowes Magneto company asked for payment of a bill going back to the early 1920’s, despite the fact that they hadn’t traded themselves for years! To his great credit, Matt paid them.
Two rings per piston is perfectly adequate.
My new 1964 Birmingham model was also fitted with 3 ring pistons, Matt obviously had quite a stock of these. Please do not leave out the bottom ring as the crankcase compression could bleed out into the exhaust port just leave an old ring in situ. Alan Noakes
Thanks again for the reply – the bore is between 73.03mm and 73.06mm diameter at the bottom of the skirt which makes it a STD bore by my data. djcb, i’ll drop you an email.
The engine is an early Birmingham one with the Lucas dynamo and I can quite imagine it is comprised of some Shipley parts. The block and head are not clubmans type but the pistons could well be based on the need to use up stocks. In fact the engine is in remarkably good condition considering it hasn’t run since at least 1970, but there is evidence of mild seizure in both bores and the rings have gummed up and begun to corrode. The gumming was so bad that despite several months of spraying wd40 and extreme patience onto the rings i broke 2 out the 3 on the right hand piston, and haven’t even attempted the left hand one yet ! I’m going to take a bit of a risk and not strip the engine any further and try and get it running again once the rings are replaced.