Gaz cooker seizes engine

[itma]

only if you`ve been putting the petrol in the chaincase[:D][:p][:D]

[g80csp11]

Neville , if you need a hand with the rebuild and setting up give me a ring 871650 ( you know the code )
I probably have a few spares if you need then , head / barrel / piston etc.. used but may be better than yours
should only take a couple of hours to find the problem then up and running by Friday

Pete

[SPRIDDLER]

Thanks all!
Had to bl..dy well work 'til 10 last night, so never got to strip her. I try not to do BBC World Service and Swarfega at 3 in the morning any more. Last 4 stroke bike engine I took apart was a 350 New Imperial engine which I liberated from a s/h spares shop for 30 bob when I was 13.
Peter. I could make good use of your help. - I'll take my head off tonight, and the barrel, (first stuffing the mouth with rag, - thanks Alan), and marking all the bits. I guess you'll be out on the Club run 'til later. Will 'phone when I've discovered what's afoot. I don't expect I'll need help to take it apart though - Thor and I have an understanding....................
I'm not playing with Alan any more. Reminds me too much of my two much younger ex-wives. He nags, he's always right, and he's retired at my expense.

[Biscuit]

In common with the rest of the human race, I am not always right, do a bit of research and you will find my howlers, in the Jampot as well as here. I shall have one more go about your ignition timing and then shut up. With your mark on the lever you are relying on the cable to position the cam instead of the stops within the magneto, cable inner stretch, cable outer compaction (is that a word?), wearing of the cable nipples or any blobs of solder wearing away from the nipples will vary your timing. To plagiarise Ken, I'll get my anorak!.

[MikeM.]

Only when I am washing it out Ken, and am out of brake cleaning spray to degrease the inside.

[SPRIDDLER]

Alan, The penny has dropped with regard to your persistent anxiety about my Wristomatic advance / retard feature. Apologies- I had not appreciated the effect that cable stretch and wear would have on the ignition setting, nor that there are 'stops' in the mag. I do need the valuable experience of all the elders - but it's taking longer to realise it than to read it!

[Biscuit]

Excellent Neville, it wasn't persistent anxiety, it was an only child failing to get his own way. When you set it up properly, the handlebar lever should not pull back all the way, the stop pin does this for you. I can understand your worry regarding the lever moving, on my teen-age G3 (mag-behind -the -engine) I was forever giving the lever a pull to make sure it hadn't moved. As a born again motorcyclist in the late seventies I was relieved to see that my G80 was the other way round - bliss!

[SPRIDDLER]

Yes, Alan - I found I was checking the A/R lever like my flies before making an after-dinner speech.

Took the head and barrel off my '54 G3LS last night with Peter (one of the Noted Sussex Section Experts). Thank goodness (Alan) for the rag in the c/case mouth. The top two rings were in 7 pieces and the piston looked 'rough cast' on the front and rear faces. It was, I believe, a wire wound type, made with a narrow vertical split from oil ring groove to bottom of skirt, and was marked 'METEOR' inside and the number '740'. The piston crown has the number 70. stamped on the top. There are more marks next to the '70' - now illegible. Very substantial gudgeon pin. The barrel was heavily marked but not significantly damaged.
The barrel to crankcase joint had a home-made gasket 60 thou thick when compressed, which had not been cut away to allow oil to pass from the top of the crankcase mouth oilway (between the tappets) to the annular ring and thence to the two drilled oilways to the inside of the barrel. Perhaps that's why it seized?
Hope to fit a 'spare' loan barrel and piston tonight. The loan barrel is a '56 and without any oilways - I'm told partly because its matched split-skirt piston has a greater running tolerance than the wire wound that seized. The gudgeon pin circlip grooves in the '56 piston are minimal and the circlips from the original '54 piston are not suitable for the '56 piston' s grooves.
But I guess you all know this already!
Hoping to be awarded my anorak at the Jampot............

[Biscuit]

Nope, didn't know that about foreign pistons, I move heaven and earth to retain my wire wounds. Had my G11 bored and sleeved from standard so I could use the original wire wounds. I think I have said this before, I'm no great shakes at carburettor tuning, but I have never ever had blue pipes.

[paul knapp]

Pipes that are first plated with nickel then chrome do not blue!
Pipes that are first plated with copper then chrome turn blue!