HELP! Birmingham Scott won’t start ??

[Russell]

Thanks for the response, we haven’t checked the timing accurately, we’ve only checked that the spark was happening with the piston “near” TDC to ensure the HT leads were the correct way round, it is “trying” to run like this. We only tried swapping the leads as a last resort as we’d tried everything else ! and it felt as though it was trying “not to run” like that so swapped them back. I would have expected it to start, even if running irregularly with the timing not spot on?

No we didn’t strip the whole engine, just the barrels and crankcase doors, and yes it is a distributer, which we didn’t “move” when stripping the engine.

[Deleted User]

Did you replace the cork seals on the bottom of the barrels? KP

[BRIAN MARSHALL]

Cylinder base rings which used to be a sort of granulated cork, are best replaced with ethanol resistant Viton seals.

[Russell]

Yes we did replace them, but from memory they were cork.

[Deleted User]

Even if they were missing completely the engine would still run albeit possibly very poorly.
I still would start with the timing, personally.

[BRIAN MARSHALL]

About twenty years ago I was asked by a local member to help get his newly restored 1929 TT Rep going as he couldn’t start it. I checked all the usual suspects, timing, spark, carb, plugs, plug leads to correct plugs, etc., and it was a dead as a Dodo. Eventually I got him to tow me, on the peri track of a disused airfield, and it finally fired and started, but would only run above half-throttle, and was severely lacking in power.
Eventually it was decided to strip the engine down. No cylinder base rings…..

[Deleted User]

Have you tried using a new set of plugs? Plugs that spark well in the open air sometimes fail under compression so it is worth fitting a new pair.

Adrian

[Deleted User]

Where about do you live Kevin?

[Russell]

@Stan Thomas wrote:

Where about do you live Kevin?

Did you mean Kevin or did you mean me ? Cheers Russell

[Russell]

Okay rechecked everything and the timing did look massively out, so much so that it couldn’t be adjusted by turning the distributer, so we ended up taking the pump-distributer unit off to check, but that all looked okay so we replaced it back on the bike. Magically the timing looked closer then, so we’re not really sure if we mis-read the timing initially or somehow the pump-distributer unit wasn’t located properly (is that even possible with the locating pin 😯 ).

Anyway we’ve now reset the timing by checking that the cylinder is at TDC then adjusting the distributer so the points are just fully open, is there a better way of doing this?

But it still won’t start 🙁 , we’re now very frustrated and ready to give up :oops:, I get the feeling it’s something fundamental and the timing being out gave us hope just to be dashed 😥

Kevin – sorry couldn’t phone you, as I don’t have your number, and as I’m not currently a paid up member of the SOC don’t have access to a current Yowl.

[dave bushell]

The distributor housing is, as you say, positively located, however, if you loosen the distributor clamp and remove a small screw that prevents the distributor being removed,the distributor itself can be withdrawn from the distributor housing and the helical gear re-engaged in a different position thereby altering the timing.
Dave

[Deleted User]

Russell have sent you a p m. Kev

[BRIAN MARSHALL]

When the timing is about correct the flat area on the side of the distributor cap will be parallel to the side of the crankcase.

[Deleted User]

Hi Russell,

I meant what area do you live – if your not to far (Orkney – Cornwall – Gobi Desert etc). I’d come over and either get you up and running or at least identify the problem.

[BRIAN MARSHALL]

Just another thought… Stale old petrol from before the rebuild ?
Brian

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