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Forty/Featherweight, wont start!
Posted: Sun Mar 28, 2010 4:03 pm
by John1952
Hi all, my Forty/Featherweight, wont start.
I have I think, tried everything!
Stored away in the shed from last season with brothers and sister, took this one out yesterday and for the life of me couldn't get it going.
Good spark,
clean points,
new fuel 10/1,
clean carb,
clear fuel line,
needle up,
needle down,
plug out, plug back in,
carb off again and stripped
carb back on
wants to fire up but just cant manage it. If I could turn one pull of the cord into two she would probably flash up!!
This is day two now and I'm getting a little stressed
Any advice please?
Re: Forty/Featherweight, wont start!
Posted: Mon Mar 29, 2010 2:35 pm
by billyboy
maybe you could try warming up the spark plug first.shove it in your pocket for a while or heat it with a lighter. also bear in mind that just because you have a good spark with the plug out it doesnt always translate to a good spark inside the cylinder where that spark is subject to the affect of 130 odd pounds of compression. so you can experiment with the points gap up to at least .025. cant think of anything else unless you forgot to pull the fuel tap on! cheers
Bill
P.S.......make sure that the magneto base plate locking screw is located in its right hole and that it is tight
Re: Forty/Featherweight, wont start!
Posted: Mon Mar 29, 2010 6:46 pm
by John1952
Thank's billyboy,
I'll open up the gap and give it another try, it's not like me to give up but yesterday I did!
I have another featherweight with a bing carb that looks well tatty and that one will start second pull!
The one I have problems with is in real good condition! Will also warm the plug.
Re: Forty/Featherweight, wont start!
Posted: Tue Mar 30, 2010 2:25 pm
by phil
Did you spray any 2 stroke mix in the cylinder before you put the plug in? Did you try a plug from a running motor? Sometimes the points need to be cleaned more than once. When you look at the plug firing outside the cylinder does the spark occur at the appropriate place between the plugs electrodes and at the right time [near piston top dead center]? How far will the spark jump in air? It should be considerably more than spark plug gap to allow for compression. Nice fat bright blue spark over at least 1/4"-5/16"[6-8mm]
Re: Forty/Featherweight, wont start!
Posted: Tue Mar 30, 2010 3:42 pm
by charlesp
Another thing to check...
...make sure the magneto baseplate hasn't rotated. A Featherweight came in last year with all lots of compression, clean carb, fat spark. Wouldn't start. The baseplate securing screw had loosened, the baseplate had rotated, and the timing was miles off.
If that's happened then rotate the baseplate until it the screw is located in the crankcase nose dimple, tighten it and try again.
Worth a look.
Re: Forty/Featherweight, wont start!
Posted: Fri Apr 02, 2010 4:49 pm
by John1952
Thanks for all your advice everybody, have now tried everything
you all suggested!
The thing I was confused with was, the bit about the magneto base-plate rotating out of position!! I noticed that the base-plate hole on the points was not cylindrical and on turning the screw either way on the odd occasion nothing happened wouldnt open or close!
I took the points out and gave them a good clean and inspection put them back in and they did not seem right. I did have a spark!
When I turned the screw again the points would not open at all, I had to use two screwdrivers, hold the points open'20tho and then lock them with the big screw into position.
(didn't feel right though) Is the small screw the base plate screw and the larg screw the locking screw??
The engine still wont run, even put the bing carb on from my other tatty
good runner featherweight!
HELP 
PS,
The screws holding the points in place 1 small, 1 large.
The small screw isn't screwing true, its all wibbly wobbly to want for a better word, Is there any way of renewing it, only it doesn't want to fully screw out, or in for that matter!
Any ideas?
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 2:34 am
by billyboy
the circular plate that holds the coil and points set up is secured by a locking screw to keep it in position. grab the plate with a hand each side and see if you can move it left or right in a circular direction. if it moves a little find that screw and tighten it. if it moves a lot put the screw in its right hole and tighten it. the screw is on the underside of the plate itself and not in the points area. its the one that actually secures the plate to the top of the crankcase and its position is crucial to timing. you will be pulling forever if it isnt right! if you look down at the flywheel from the front of the engine then the hole where the high tension lead enters the base plate should be at 8 o' clock if the base plate is in the right position. if not then it has rotated so the screw is loose. good luck with it!
Bill
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 9:05 am
by John1952
Please forgive me if I sound dumb!
There are 2 screws,
1 large,
1 small.
The large screw ( the one closest to the flywheel)I can take right out and remove! I take it thats the securing screw?
The small wibilly wobilly screw adjusting screw? (closest to the coil) I cannot take this one fully out, is that correct?
PS,
there was no loose screws!
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 9:48 am
by John1952
billyboy wrote:the circular plate that holds the coil and points set up is secured by a locking screw to keep it in position. grab the plate with a hand each side and see if you can move it left or right in a circular direction. if it moves a little find that screw and tighten it. if it moves a lot put the screw in its right hole and tighten it. the screw is on the underside of the plate itself and not in the points area. its the one that actually secures the plate to the top of the crankcase and its position is crucial to timing. you will be pulling forever if it isnt right! if you look down at the flywheel from the front of the engine then the hole where the high tension lead enters the base plate should be at 8 o' clock if the base plate is in the right position. if not then it has rotated so the screw is loose. good luck with it!
the screw is on the underside of the plate itself ? sorry Bill i'm even more confused! Any pics?? cant find any on the site!
Bill
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 10:39 am
by billyboy
mate the screw i am talking about is neither of those two! can you imagine either of those being strong enough to hold that big silver base plate in position? look underneath the plate near where it joins the crankcase!
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 11:10 am
by John1952
Sorry duh!
I thought you meant the points silver base plate
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 11:43 am
by billyboy
ok now re-read my last couple of posts..........they will make more sense now! cheers
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 1:21 pm
by John1952
billyboy wrote:ok now re-read my last couple of posts..........they will make more sense now! cheers
There is no slack in the base-plate, and the large stainless steel screw on the underside was also screwed up tight! and in the 8o'clock position!
Thank you for your help and patients. Still a non runner!!
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 2:04 pm
by charlesp
Okay, back to the start. First, we can assume you have compression I suspect.
So it's either fuel or spark.
Can you confirm you have a spark? Take the plug out, and lash it with sellotape/insulating tape or whatever so that the steel portion of the plug is in good contact with the motor. Then put the plug cap back on and spin the motor. Is there a spark? A good fat one?
Come back to us!
Re: Forty/Featherweight, wont start!
Posted: Sat Apr 03, 2010 2:32 pm
by John1952
I bought another new plug and yes a good spark! I cant say it was a big fat blue one though! Also good compression
I also put on the bing carb from my other running featherweight, still no joy!