Much appreciated Tam

[Nudge]

I will just say Im on the fence with this one

[Keith.P]

I don't honestly know what's right now, as I was only going by what I have been told on this site by the "experts", as we are not allowed to post hearsay, just facts, ring any bells.
Anyway the SD has a good crank fitted, capped floating gudgeon pin, a good piston and two new rings, I didn't want to use the one ring piston on this, it still has some green paint on the head, so it will be left as is, unpainted.

[headdownarseup]

Nice work Keith. Keep us updated with its progress. (1 ringed piston? you're having a bubble KP aren't you?)

My input for what it's worth on gudgeon pins, the vast majority of motors that i've stripped and rebuilt including 40's 100's and of course a whole range of 102's old and not so old, have all had the hollow end of the gudgeon pin (where fitted) facing towards the ignition.Whether or not these engines have been apart previously we will never know. Rightly or wrongly this is how a good proportion of them were/are.
Once i've gone through them i refit the hollow end of the pin towards the exhaust port for the simple reason that the pin won't fill up with oil from useage. No point in having oil where it's not needed is there!
Either way you choose to fit the gudgeon pin won't really make a drastic difference to how the engine performs for us mere mortals, unless you're a "racer" of course then it becomes slightly more of an issue.


Jon

[Keith.P]

One ring Hepolite pistons are not that uncommon Jon, If I remember correctly seagull tried them, but found a problem, overheating or something, so ended up parting them out to the seagull agents to get shot of them.

[tambikeboy]

Two sold on EBAY this week as common as a number 9 bus

[Charles uk]

Jon which service manual did you find the pin hollow end up in?

All of mine have no mention of them (4 different classic ones), though the Kingfisher one says "when removing the gudgeon (wrist) pin it is important to note the location of the "blind end" of the pin.

The one ring pistons were discussed here many years ago, nice find Keith, well remembered, what was it in?

[headdownarseup]

re those pistons, the one on the left has a different transfer "slug" to a common 102 piston. A proper 102 piston has a rounded "slug" when viewed from side on and not a square or oblong version.NEVER seen a 1 ringed piston in a 102. I think the 1 ringed piston was/is from a century type engine, and possibly an early century at that (very late 50's perhaps). Wider transfer port in the older 102's compared to the centuries, hence the "slug" is the complete width along the top of the crown. Century's seem to have a smaller "cut away" with a noticeable STOP at each end, due to the smaller/narrower port.
From what i've managed to get my hands on to date regarding 102's, it's not until the 60's 102's that a drastic change to the cylinder internals takes place from wide to narrow transfer port, and subsequently a slightly different piston to match.

Just checked a "pirate copy" version i have of service sheet no.3 and could have sworn blind it mentioned the positioning of the "wrist pin" but it doesn't. BUT i will say this. It does leave some room for misinterpretation. No diagrams, just instruction. However you choose to remove the pin is one thing, how you choose to refit it is something different again. Just saying...
I can't comment on anything from the QB range as they're not something i have the slightest interest in.They just don't appeal to me.If by some strange twist of fate that 1 landed in my lap i might be tempted to see what all the fuss is about, but highly unlikely.

So, apologies once again headmaster. My bad
1000 times i must try harder

[Charles uk]

You don't have to apologise to me Jon, I thought you were bullshitting but I did check to ensure I was right, you might have to do something similar on your one ring piston post.

[Nudge]

I had a look in my copy of the Clymer service . repair book and found on page 103 this

Im not going to say who is right of wrong you can work it out yourself!

[Charles uk]

Didn't spot that bit thanks, we found a few errors in there but as there are so few copies around, didn't feel it merited correction.

A bit like the book that came out of Vancouver 10 years ago, John spent quite a lot of time correcting the free copy they sent him, which he returned, only to be told that they would have to sell the 1000 + that they had had printed before the would consider a reprint!

[RickUK]

I've got a one-ringed piston I(if I can find it) anyone welcome to it as a curio for the price of postage.

[Keith.P]

Have you Rick.

[headdownarseup]

For what it's worth, i think today a 1 ringed piston is a complete waste of time and money unless you'd want one as a curio, hence why i've never bought one.
I have seen them before and waited patiently for someone to comment. It's a pointless waste of money on something useless like this. Interesting but pointless.

I try not to bullshit Chas. for fear that i might get sent to my room with no supper! What's wrong with my last post? Or is that something else i'm gonna have to put up pics to show. Give us a clue! I know i'm not always right, but i'd like to learn more about the stranger side of seagulls.

So it seems i was sort of right after all with these wrist pins. Upside down or right way up,(whatever that might be) they are what they are. It's not always as clear cut as we'd like it to be. Like i said before, open to some misinterpretation. (another reason why i don't like collecting old paperwork)

[Keith.P]

I myself wouldn't say the single ring piston is a complete waste of time, like the seagull carry handle, it is a complete waste of time and I know it is, I have one, as its part of British seagulls history, plus I wanted one.
I also have a brass remote fuel tank, among other things, its not that useful, but I wouldn't class is a waste of time.
Maybe my outboards are a waste of time in someone else's eyes, but not mine.
The piston was a free-bee, so not a waste of time for me, plus the single ring piston has been talked about on this site before, so its nothing new.
As far as the wrist pins, goes, I would have been told rightly or wrongly from this site years ago, that's where most of my knowledge of seagulls comes from, If I had been told I could only operate a seagull sitting in the lotus position with a feather up my jacksie, then it would have come from this site.

[Nudge]

Did Seagull themselves do a repair hand book? Or was it expected that you sent you engine in to them to get repaired?