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Re: Square Four MkI restoration complete - almost....
Posted: Sun Apr 28, 2019 8:55 pm
by Gui.dorey
Gave up for today. Today she didn't fire once. After a few attempts the plugs are definitely wet. Still not sure why she is not strating. Too advanced? Too retarded? Too rich and flooding?
I'll try Paul Jameson's method next time and re check the timing. Thanks for all the tips as always.
Cheers
Gui
Re: Square Four MkI restoration complete - almost....
Posted: Sun Apr 28, 2019 9:45 pm
by simon.holyfield
Re. The timing. You've checked both the ignition and the valve timing? I got the valve timing wrong several times when I built my engine. I found it quite confusing that the crankshafts roll in different directions.
Re: Square Four MkI restoration complete - almost....
Posted: Sun Apr 28, 2019 10:34 pm
by Gui.dorey
Yes, valve timing according to Bruce Longmann's method and it was spot on to maybe 1 deg. I had to repeat it about 3 times before I got it, and did get confused as well at the beginning. Again,I believe it's something with the mixture because she ran twice for a few seconds before going out and didn't sound that bad. If either the valve or ignition timing was completely off, she wouldn't have run at all. I'll just have to keep at it.
Re: Square Four MkI restoration complete - almost....
Posted: Sun Apr 28, 2019 11:11 pm
by simon.holyfield
Gui.dorey wrote:I'll just have to keep at it.
I think you're right. Mine is not so easy to kick over from cold, and it was worse when the engine was tight. Those seven Maudes Trophy schoolboys must have either been pretty hefty or been kicking over a hot engine.
Another thought - I have my kickstart mounted just high enough to clear the toolbox and even then I start the kick from maybe 10 o'clock, to maximise torque on the starter. Of course, this limits the amount the engine turns over.
Re: Square Four MkI restoration complete - almost....
Posted: Mon Apr 29, 2019 5:09 am
by john.whiting
in those days schoolboys played 50 a side rugger every afternoon on fields of bare pebbles,and had cold showers to keep their minds on Greek and Latin..........so maybe they were putting some force into the crank.
Re: Square Four MkI restoration complete - almost....
Posted: Mon Apr 29, 2019 12:24 pm
by Bob.Murphy
john.whiting wrote:in those days schoolboys played 50 a side rugger every afternoon on fields of bare pebbles, and had cold showers to keep their minds on Greek and Latin.........
Ah yes; I remember those days (Boarding School in the 50's)

.
Bob.
Re: Square Four MkI restoration complete - almost....
Posted: Mon Apr 29, 2019 8:22 pm
by paul.jameson
The schoolboys were kicking over a Cammy, so 600cc at most with easy to turn roller big ends and ball mains. A 1000cc engine with lots of whitemetal bearings is much more difficult to turn.
Re: Square Four MkI restoration complete - almost....
Posted: Tue Apr 30, 2019 6:23 pm
by Ian.McCandlish
Sorry I'm a bit late to the party, but I find my '49 Sq.4 starts with the bi-starter halfway out and with the throttle slightly open. I always give it 4 kicks with the ignition off to get some fuel into the cylinders, then off we go! If I try to start it with the lever fully out it wont go!
Old bikes are like people they all have their own foibles
Regards
Ian
Re: Square Four MkI restoration complete - almost....
Posted: Thu May 02, 2019 6:54 pm
by Gui.dorey
Uhuuuuuu!!! She‘s running!!!
Sorry for the poor video but not enough hands
In the end it went like this:
Tried Paul Jameson‘s trick and she fired, but didn‘t start.
Re tried a few times and sometimes she would fire, sometimes not.
I then closed the bistartet completely and opened up the throttle a bit. After a few attempts she finally burst to life with an amazing sound!
She would want to die however if I closed the throttle, until I pulled the bi-starter to the mid position. She then seemed to be happy that way. Then I noticed the massive oil leak at the front of the engine and shut her off immediately and the fun was over. The oil line to the rockers came apart at the soldered seam near the fastening to the rocker box. so will have to fix that. Didn‘t have time to check the pressure gauge either.
Very excited but time to rest my kicking leg. It‘s been a looong time since my rugby days as second row, but I do notice my leg muscles are coming back - nearly ready for the scrum, I‘d say.
Re: Square Four MkI restoration complete - almost....
Posted: Thu May 02, 2019 11:04 pm
by simon.holyfield
Excellent news Gui, well done!
I had a oil line with a duff joint too. Couple of tips: did you use a copper washer at the rocker box joint? A fibre one lasts for a while but will eventually burn and leak.
Secondly, do you have the rocker oil line and the gauge line the right way round? Contrary to what you might expect, the gauge is the larger of the two.