ignition coil removel

Just spent 2.5 hours trying to remove the coil !!!!! whoever says its ok to replace by removing the petrol tank,is having a laugh because believe you me its damm impossible...... unless you have child like hands and a socket or spanner that bends 180* and then have about 1inch leverage to turn the damm thing in,forget it guys dont even try, now going to spend more time taking the engine out which is what i should have done in the first place hope this new coil does the trick as its breaking down after getting hot under load.

If it's getting hot, probably a short circuit or bad earthing.
Or are you running a 12v engine?

O dont say it could be something else? i have changed the plug,plug cap,checked points(good),condenser(no spark at points) good?,fitted fuel filters,carb ok, my only other worry was the coil (nr points) could it be? ,just waiting to recieve new ignition coil(monkeybike uk) and will fit hopefully tues,wed. the earth under the ignition coil looks good bare metal showing,what other earth could cause this??

waynus is there only you chatting and giving advice,weres all your buddies? any one out there.................................
just been watching ebay this week loads of spares,engines,frames, etc etc all from the 1 seller,must of had several bikes all pretty much ready to put back together,
but decided to get rid

o its a 6volt engine only done 1250 miles.

Hi
I had a similar problem and it was the coil and after reading a post by James about fitting a replacement fuel tank I decided to remove the engine which is fairly straight forward I also ran a seperate earth wire back to the battery box just to make sure it was as good as it gets.I got my coil from one of the ebay sites I think it was from the far east.
When you look at the age and working conditions these parts endure they do pretty well, I also think that the designers thought they were pretty tough which is why it is located inside the frame rather than externally.
Mine took a while to sort but it was well worth it on a sunny day whizzing around the lanes of Essex and Kent.
Tufty

Sorry arny, i dont like giving advise unless i know what it is 100% it not fair you spending money what you dont have too because i got it wrong You will find waynus and tufty are very good on theses bikes and what ever they say i stand by, good luck m8 regards lee

Cheers guys,will update after fitting new ignition coil,and take her out on a long,ish cruise, i think the wife will have to follow me in case i breakdown for the 3rd time Could the primary coil near the points cause this to happen
anyway just recieved a new flywheel pulley off ebay for £8.00 ! good value i thought ? and such a great and helpful seller,complete with intructions, i believe they make them, very helpful...if you need one then here are their details www.rexcauntracing.com or info@rexcauntracing
arny.

Hi
I dont think so as 1 coil is for the battery recharge/lighting circuit which is why they are nearly useless and the other is the ignition source coil which starts the ignition spark trail ie when the flywheel which has a magnet in it approaches the firing point the magnet induces a voltage in this coil which is the primary voltage supply to the HT coil which transforms it into a high voltage for the spark.
tech stuff over,
As IGNITION SOURCE COIL a simple coil of copper wire it should either work or not (look for physical damage) this is where I get proved wrong back to LEEANDALY's comment on giving advice, but the HTcoil does a lot of work and can get very hot and so break down. Normally they breakdown (lack of spark or weak spark) when under load this could be heavy acceleration or when going uphill in a high gear and so the engine components are under heavy load and the spark produced is not strong enough and you get what appears to be a timing issue.
Things to recheck which are critical on a 6 volt engine
Timing
Contact gap
Spark plug gap
Carburation
valve timing
any of these could have slipped when you were on your journey
Just persist and you will sort it or take it to one of the specialists MBUK or OORACING who will sort it but at a cost
Having been where you are now I can appreciate your frustration but DON'T GIVE UP

Problem fixed !!! it was the ignition coil,managed to fit new one by removing the air filter and carb +petrol tank,battery,and fuel pipes......... there was just enough space behind the air filter casing for a small 10m spanner,what a job anyone thinking of replacing coil, DROP THE ENGINE save hours,mind you, gald i did remove the tank as the reserve fuel pipe split when bent pipes looked fine but when bent a little they all split ! they were 36 years old.Anyway took her for a 10 mile trip ran perfectly never missed a beat ! 44 on a straight, light winds, pulling 12stone+ i bought some petseal ultra(monkey bike uk) but never used(tank looked ok) fitted inline filters instead, anyone who is thinking of sealing there tank can have mine if interested ?? let me know.. it is dated up to oct this year.

Yes
Result
I am pleased you are sorted now all you have to do is ride your ST have fun
Tufty

Cheers Tufty,shame we car,nt meet up (ride out) 150 miles is pushing it a bit though ! dont no of any other members/owners in yorkshire ?