I am new to the forum and the joys of Austin 7 ownership.
I have recently become the proud owner of an RTC Trials special. The engine was a little smoky but also had clutch issues. So I have stripped it. Compression before was 107-110 psi. Which I thought was probably OK? The clutch issue, violent vibration, was I believe caused by a loose lever adjustment grub screw which meant one lever was considerably lower than the other 2.
The engine has confused me!!
Its a 2 bearing Ruby I believe with a 1 1/2 inch pressure fed crank. From the picture attached can anyone recognise the piston and rod. What I find surprising is that the bores show little wear, no ridge and within 0.001 throughout but the piston fit to me is very loose 0.007 and ring gap 0.025. Big end shells are perfect and unmarked with part number 2390RA std. However the pistons have a little play on the pin,very slight, which appears to be an interference fit in the rod. Is there a reason for this fit or is it just poor build quality. I wonder if second hand pistons have been used with new shells and rebore.
It also has larger inlet valves double springs and modified ports.
Thanks
Pete