557 SV piston

[charvey]

Hi All
I am looking for a standard piston for my 1929 557cc SV Ariel Has anybody out there got one or a +20 I need to get the barrel sleeved as the original barrel has damage to the bottom of the sleeve and cracking going up the barrel slightly, Clive.
PS I am going to Stanford Hall to the founder day to look around there for one but if anybody has one please let me know thanks.

[Roger Gwynn]

I have an Ariel piston on standard, but before you get too excited it has light seize marks, nothing terrible, only one ring with .008 vertical clearance in the groove. There is a pin, but no pads and the pin is a tad rusty. Not perfect but would work and fill the hole if you can't find anything better.

[charvey]

Hi Roger,
If thats alright with you thanks I will give it a go let me know about postage etc., and i will contact you back.
Just got back from Founders day and am sorting out and putting my jumble stuff away so a bit of a mess at the moment in the garage.
Thanks Clive.

[Roger Gwynn]

I'll pop it in the post tomorrow, buy me a drink sometime.

[charvey]

Hi Roger,
That's very good of you.
Just another thing I have been looking at the barrel thickness and the bore, and there is not much metal there will it take a bore and liner or will it weaken the barrel at that point just above the base I have seen barrels break off, because the liner is only shrunk in and doesn't really add any strength to the barrel or does it or is the liner really thin which it would need to be.

Just another worrying thought. Thank again for the piston if I don't use it it will be returned. Clive.

[Roger Gwynn]

The cylinders are thick enough for a liner as long as the liner is not overly thick of course, there is more meat on it than appears. The problem with sleeving a sv cylinder is the distortion due to the unequal heating around the ex port. Someone was writing about that on here recently. You don't have a lot of choice, finding another usable cylinder will not be easy. If there is only minor damage at the bottom of the spigot, I would be thinking about leaving it as it is, perhaps drilling a hole at the end of the crack or breaking a bit off if it is likely to fall off. Chamfer the edge and continue to use it, of course it depends how bad it is. Bear in mind that pistons rarely come all the way to the bottom and the lower section is there to reduce the amount of oil going up the cylinder.
I meant to say that if you don't use the piston I would like to have it back.

[charvey]

Thanks very much Roger the post man delivered the piston today and I have polished it up and it looks better than the 60+ I took out.
I am going to get the barrel resleeved as the cracking is quite bad and there is a bit missing already so I will go for it, I can get some rings made a friend has told me where to go and another firm who will hopefully fit a liner I will see how I get on with it all,
I have been cleaning and checking every thing today and making new gaskets and cannot see anything else wrong thank goodness.
Thanks again I will meet up with you at a do and get you a drink+ Clive.

[dave.owen]

Clive, for rings try Cox and Turner in Yeovil, I've always had great next day service.just quote piston number and size.

Dave

[charvey]

Hi Dave,
Thanks for the recommendation somebody else has said how good they are. I am just holding fire till I get the barrel sleeved taking it next week to see what they can do for me. Clive.

[RayBlack]

Has anyone in the club ever seen a non original piston fitted to a 557cc side valve? My '28 engine that originally came from the Czech Republic had been disassembled when it finally came to me, but apparently had been running with a 3 ring piston. The small end bush had been replaced to fit a smaller gudgeon pin with circlips. When I saw the piston and bore some weeks before I bought the project it looked pretty ugly - scored and generally unhealthy. Although the conrod and bottom end seemed to be good. No signs of the piston hitting anything on the up or down stroke. Unfortunately, (not the expression I generically use when discussing the issue ) the piston went 'missing' during the transfer of the rolling chassis and related parts to me, so I cannot use said mystery piston to investigate further.
Given the lack of oversize, or apparently, any, original pistons for these engines, if one was thinking of sleeving is there not a later model side vale piston that might be pressed into service?