MG
The Classic Marque

Um---something wrong with your measurements there John
There's no way a 1.003" piston will fit in a 1" hole. that's a .003" interference fit
Size on size is a light press fit
.001" per inch is normal press fit
.003" is a very heavy duty press fit, you'd need a decent press to get that in.
I'd suggest you take the seal off and try the naked piston in the bore on it's own--the ...

Nick, I just meant a bit of "wiggle" room if it was only a few mm out. But it sounds like you've identified the problem. They're big hunks of unwieldy metal aren't they. I'm amazed mine fitted after pulling it about.

Bill, they don't actually adjust, do they? Unfortunately I'm due at the dentist shortly, but I will get straight back to it afterwards.
Overnight, Guy's and Dave's posts have given me a Eureka moment. When I was doing battle with the bonnet hinges, other things intervened, and the bonnet was left hanging with a rope at front centre for a couple of days. Perhaps that's when it stretched, and ma...

Thanks Paul - recommendation noted. I confess I resorted to asking a question about the dimensions of the original YA m/c piston in "another place" - to no avail. I don't suppose you have a photo of one of your originals? In fact do you have one for sale?
My Lockheed cylinder was resleeved in Cairns by a brake specialist called Knights Brakes. I suspect that Willy R is right - non original pis...

Not sure who did your rebuild JP ... but there is a reason even here in the US there is only ONE company I trust (from bitter experiences elsewhere) with Y Type brake Master Cylinder rebuilds and that is C&C in The Netherlands. And yes, I ship stuff to them from the US and have it returned to me in the US and I pay for premium insurance both ways as it is actually less expensive because they do s...

Good to see you on the Y side Bob.

Keep in touch if you need assistance Tony B, Tony S and I are all here for you. As is everyone else in the IMGYTR.

Best wishes

Paul

Another endless procession of whales yesterday, at any time during the day there'd be four or five going through. Then early this morning just after sunup there was a loudish wacking noise and looked out and there was one probably only 100 metres out from the beach, rolling over and wacking his side fin into the water--has gone a bit quiet now but i'm sure there'll be more-----great stuff.

K,

Well understand your comments. I probably did not post enough information. Replacing all brake pipes and fuel pipes while engine is out. Replacement engine fully assembled except for new rocker shaft I am waiting on. Gearbox in pieces waiting on parts. When I have replaced pipes and got engine and gearbox in will do one corner at a time, doing bushes and brakes. I expect the car to be dr...

Nick, will the pegs not move backwards so they'll fit or are they miles off (they do adjust a little)?

Guy

I could imagine the bonnet sagging, as you suggest, but Nick's seems to have gone the other way. Bizarre.