So, following my post earlier today, I think I have a problem.

I tried to start her up For the first time today, used the great information on this website to set up the mag - checked on the side of the exhaust lifter that I was getting a spark, all ok.

After putting petrol in the tank for the first time and discovering it was leaking at almost every point possible, I had to spend a while tightening up taps etc.

So to cut a long story stort, I couldn't get the bike to fire, not even cough. I'm wondering if by painting the head I've prevented the current getting to the plug.

Also, I had a smell of the exhaust, I couldn't really smell much petrol. Am i doing something wrong?

email (option): Adh325@hotmail.com

I've never come across a situation where a spark plug failed to cut enough of a thread to make some metal to metal contact. If in doubt, have a scrape around where the sealing ring sits on the head.

Is the plug coming out wet ? If you have a spark at the correct moment then it should be doing something.

How old is the fuel ? Try draining it out and checking for ethanol-induced water globules.

Hi Rik, the fuel is new - this is a newly re-built bike.

The spark plug was not wet when I checked it - perhaps the carb isn't set correctly?

email (option): Adh325@hotmail.com

The obvious question but you have rechecked the ignition timing. I reset mine yesterday and being newish at this it took the fourth go before i got it right and the old girl would actually fire.
I did have a smell of unburnt fuel from kicking the first three times though so if you aren't getting that then a work though of the fuel supply sounds worthwhile.

Hi Andy..Iains advice is good...you must be 100% sure you have the timing set correctly.
It seems you have a good spark so that in itself won't be the problem.
It is simply a process of elimination..if you have a good spark that you know is correctly timed, but you stll have a problem, then fuel supply/carburation will be the next thing to concentrate on.
...Ian

When I first had my bike I had a problem starting the bike due to riding loads of electric start bikes. My experience had rusted away. To overcome this I resorted to 'damp start'. I sprayed some into the carb and turned the motor over with the valve lifter in use. I sprayed again and then started in the normal manner. If you do not get the bike to start (or chuff) then check the ignition system. If it fires and dies check the fuel system. If the float is sticking or a fuel flow problem is present, starting in this way will sometimes cause the problem to sort itself out.
Hope this helps.

email (option): stinkypete80@hotmail.com

Iain, you've become used to electronic ignition on the old 'Come-an-go' haven't you ? I too miss the security of seeing a strobe mark align at full advance. These old clunkers are all so damned approximate !

Andy, how are you trying to start the bike ? alongside or astride ?

I have the devil's own job to fire mine up from in the saddle. Somehow the odd knee movement combined with catching the rear of the saddle means that I can rarely achieve the flywheel acceleration necessary.

Ian, I know this is a bit cheeky, busman's holiday and all that but are you likely to have your electronic points opening tool with you in France ? I'd be quite interested to see how close I've got mine (and I'll give you a beer and a crate to sit on so that you can laugh at me trying !)

Im fairly certain the timing is correct, thats if I've interperated the instructions correctly. I found TDC, wound back 11.1mm, made sure the points were just opening up at this point. The point carrier was sitting at about 10.30 when this happens. Will definitely check again though.

I think perhaps the carb isn't set right, although it's wet with fuel it doesn't seem like fuel is getting into the barrel somehow...otherwise the plug would be wet surely...

email (option): Adh325@hotmail.com

If the bike is being started for the first itme after a rebuid, it could be that the compression is a little low, if you have low compression you also have low suck hence the dry plug. Put some oil done the plug hole turn the engine over a few times put the plug back in and try again the oil will give a temporary seal to the bore and hopefully improve the suction.

Andy I'm probably stating the obvious! But did you set the timing on the compression stroke?
Providing the timing is correct and you have a spark, and that the cam gears are all in their correct position, then it will be a fuel/carb problem. Ron

email (option): ronpier@talk21.com

Oh Ron, you might just be a god...I remember checking it was on the compression side first, then got distracted by the fact the engine sprocket cush nut was coming loose. I may have rotated the engine whilst tightening it up. Bugger.

I'll post a video if I get it going! Thanks for everyone's help.

email (option): Adh325@hotmail.com

email (option): viaconsu "at" planet "dot" nl

i might be wrong but both my bikes the point are at about 1050 ish that if i understand you looking at the points like a clock i am talking about a M20

email (option): roger.beck@node6.com

email (option): ahum@quicknet.nl

Just set it again, this time though the feeler comes loose at about 10 o'clock. Should they all be the same? I'm using a 0.0015 gauge.

email (option): Adh325@hotmail.com

Too thick! Use fag paper.

email (option): viaconsu "at" planet "dot" nl

Briefly got it to go! Only runs for a second or two, and only after I've primed the carb. So must be fuel delivery issue. The rubber washer I used on the large primary nut has disintegrated already, so I've managed to make a cork one from the old clutch sleeve cork which was in good condition. With the union nut off, there seems to be a small hole in the underside if the carb - does this need to be kept clear?

email (option): Adh325@hotmail.com

I just stripped the carb off my Enfield WD/CO. Yes there is a small hole just above the bottom threads that lines up with a drilling in the jet block.
I was called for convoy duty on Friday at the Trucks and Troops show at Beaulieu. My bike was OK on fuller throttle openings but was getting progressively worse at slow speed or tick over. I was also having trouble restarting the engine. On Saturday I stripped the carb, and decided to remove the petrol tank to gain access to the throttle cable ,as I felt it needed replacing. That's when I found all the petseal that had been installed about 15 years ago by it's previous owner was now swilling about at the bottom of the tank. So a big clean up is imminent....Bollocks to Ethanol Ron



I have shown the wrong side of jet block, but the drilling goes right through.

email (option): ronpier@talk21.com

That's a strange old drilling Ron. What's the carb number ?

No sign of that airway (or drain ?) on the 16H carb, nor on the old A7 body that I've got lying here.

Is your tank leaking now that the petseal is out or was it just there for appearances ? My tank has got some sort of red lead paint in and weirdly, it seems to be 'effin' efanol proof.

Cheers Ron,

I was referring to a hole actually right on the bottom of the carb (sorry, I didn't describe it very well last time), I was wondering if this needed to be kept clear of any seals etc...is it perhaps something to do with the pilot jet? Could explain why I can't get my bike to run for more than a couple seconds, assuming the seal I put in partially obscures it.

email (option): Adh325@hotmail.com

That is indeed where the pilot mixture receives its fuel. The opening doesn't appear critical as it is partially obscured by the standard fibre washer. It obviously shouldn't be covered completely.

The thickness of the washer affects float chamber position and thus float height (but in my experience, it can be a bit either way without causing problems).

Rik I just had a look at my M20 carb. The slot that locates the jet block is extended up to expose that drilling on the left side of the jet block.
This carb for my CO is correct and is a 276AC/1A
and no the tank is not leaking, so I'll forget about a sealant.

Also, the correct fibre washer in the bottom union will cover just 1/3rd of that hole you mentioned Andy.

Ron

email (option): ronpier@talk21.com

Andy
Has it "wet sumped"? If the crankcase is full of oil they will not start or just runs a few second because the oil drag on the crankshaft stops it

email (option): gasboy@btinternet .com

Hi Peter..did you get my e mail reply about the B31 crank?..Ian

Ian
Yes I did thanks. I took it to Dave Plumb as his place is closer to me than Plymouth, and I could make it there and back in a day. He made a good job of it. But thank you for your advice, and I hope to use your services in the future.
Best wishes and many thanks, Pete

email (option): gasboy@btinternet .com