A frustrating morning

[lewis onions]

We thought that before the TT Rep was disassembled for painting and plating it might be a good idea to see if we could get the engine running. The bike has a Binks/Amac three jet carb, and a BTH mag-generator. The usual checks were done – timing is set( and checked) ; great big blue sparks are being emitted from the mag; carb. float level has been set at just about level with the front (middle -sized )jet; new petrol added to a slave tank; crankcase doors removed and wells mopped out.

The first kick produced an encouraging “pop” and we duly swapped the HT leads. This proved to be very much a false dawn as for the next hour or so there was no life whatsoever despite generous application of the kick-starter. Wells mopped out again, timing checked ,float level checked again. The first kick produced a kick-back but then nothing more. More checking of the carb and the addition of another washer to the bottom of the float chamber appeared to have set the float level perfectly.

The next series of kicking resulted in the engine firing occasionally but not enough to allow it to pick up and run. I have retired with a sore knee and hip to reflect and gather thoughts. Has anyone any ideas ?

[scott596]

[attachment=0]DSCF0002.JPG[/attachment]Hi Lewis, welcome to the Scott world, usually if a Scott engine has been left for a while the internal coating of oil drains or evaporates from all the bearing surfaces including pistons and gland faces, the result is that when you start to kick it over it is unable to create any suction, even if you get the pistons coated in oil the dry glands can still let air in, best plan is to take off transfer port covers and with an oil can pump oil all round the top of each piston and kick over to coat the bores next take the top cover off the pilgrim and fill up each side with the oil can, this will get a lot of oil into the engine in the shortest time, you can now start kicking again or alternatively buy one of my roller starters. Alan Noakes. scottworkshop@hotmail.co.uk

[lewis onions]

Thanks Alan

Not so frustrating this morning ! We followed your suggestion and added a generous helping oil to the pistons via the transfer ports and through the oil ports – we are starting without the pilgrim pump at present. After easing the oil around with several hand turns of the kick-starter we replaced the ports, the carb. and added long-reach spark plugs. Three kicks and the engine fired and ran with the expected plumes of smoke. Regrettably this proved to be another false dawn as even repeating the procedure wouldn’t cause the engine to run again although the first kick each time did cause the engine to fire.

Further investigation suggests that the engine is blowing rather than sucking through the carb. inlet and yet more investigation shows that air is escaping past the left-hand piston as it moves up the barrel, noticeable through the transfer port where the oil can be seen and heard bubbling- the right-hand does not seem to be doing the same. The engine has been stood for a number of years but seems to have been rebuilt – the piston rings appear new and the water jacket is newly painted.

Am I right to suspect that a top-end (re)re-build is necessary ?

[lewis onions]

PS. I have suggested that my wife put an order in for one of your roller-starters for my Christmas present !!

[NIngram]

Although not available for another week as working away, I can always stand & offer support next time you attempt, Dave made a nice little gadget to work out if inlet was sucking as it should if that helps ?

[scott596]

Forgot to say a Scott engine should never be started without having sufficient oil in the crankcase, should be up to the bottom of the conrod, this ensures continued oiling of the piston when the engine starts, if you had to wait for the pilgrim to build the oil up to this level it would take an age and engine damage might result. You have proved that when the pistons are coated in oil the engine starts so if the oil coating continued then there is no reason why the engine could not continue to run. Alan Noakes. scottworkshop@hotmail.co.uk

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