Allotment Gardening Advice Help Chat
Chatting => Equipment Shed => Topic started by: wilf1234 on January 21, 2021, 13:47
-
I have inherited a Norlett Tillermate - it's be undercover outside for x years, and unfortunately uncovered for the past 12 months.
Engine turns but no spark. I've changed the plug, taken the pull cord off and cleaned the points, but still no joy - it's an absolute mess in there. I only crudely repositioned the coil. Am I wasting my time?
One problem is that when I took the coil off to clean the points I didn't spot where a bare copper wire was attached. There's another insulated wire from the coil which presumably goes to a condenser somewhere, but does this bare wire indicate that someone has tried to bodge it previously as it looks out of place and can only really connect back on the fixing bolt for the coil? I've circled the bare wire in the attached photo.
As you can probably tell, I have a dangerous amount of knowledge! Any advice gratefully received.
Would it be better just to look out for a replacement engine? (is that possible?) (the existing engine turns over ok and seems to have compression)
Cheers
W
-
Looks like it needs a good clean up for starters but you know that.
This is what I would do
Reset the airgap. Looks to me like the wire with the ring connector should go to Earth try putting it on one of the small bolts that holds the flywheel cover in place. then check for a spark.
-
Looks like it needs a good clean up for starters but you know that.
This is what I would do
Reset the airgap. Looks to me like the wire with the ring connector should go to Earth try putting it on one of the small bolts that holds the flywheel cover in place. then check for a spark.
Thanks - I judged the gap by eye (which has worked before on other machines). Does it need to be more accurate than say sticking a piece of scrap sandpaper in?
PS I put a meter on the coil and it seems to be fine ohms wise (3k)
Cheers
-
I would try using a small square cut out of a plastic milk container (nearly said bottle) as a feeler gauge. If that doesn't give the correct air gap I will be surprised. Or to do it the posh way you could google the correct specs for your engine and use a feeler gauge.
-
I would try using a small square cut out of a plastic milk container (nearly said bottle) as a feeler gauge. If that doesn't give the correct air gap I will be surprised. Or to do it the posh way you could google the correct specs for your engine and use a feeler gauge.
You can probably tell from the state of my workshop that I'm a scrap plastic type of guy rather than Gucci feeler gauge!!
-
Let us know how you get on
-
No joy - still absolutely dead....
-
No joy - still absolutely dead....
Do you have a spark
-
and petrol getting to the pot
-
No joy - still absolutely dead....
Do you have a spark
Nope, no spark. Coil tests OK.
Cheers
-
On off switch ?
-
On off switch ?
Nope, just the throttle lever....
-
I would splash out on a new condenser/Coil
-
Double check you have the points gap correct (0.020") spotlessly clean and that they are closing. If it has a single wire from points to coil there must be some other way of stopping it, as normally there is a second wire from points to some type of "earth to kill" switch. The wire you ringed on the photo is the earth for the coil and must be trapped under a coil mounting screw. The air gap should be 0.006" to 0-010" for 3hp B & S and 0.010" to 0.014" for 5hp engines. This should be checked at the magnetic bit of the flywheel. Normally you get a good fat spark as you flick the magnet past the coil. You don't with the later, contactless coils, lucky if you can see one but with no points to corrode or points pushrod to stick, they are more reliable and can be retro-fitted, as long as you know what engine you have.
-
Hello I was at a machinery dealer last week picking some parts up ,he had a N,O,S (new old stock ) 3.5 hp Briggs &Stratton engine for sale it's the engine used on ATCO mowers jezza
-
Double check you have the points gap correct (0.020") spotlessly clean and that they are closing. If it has a single wire from points to coil there must be some other way of stopping it, as normally there is a second wire from points to some type of "earth to kill" switch. The wire you ringed on the photo is the earth for the coil and must be trapped under a coil mounting screw. The air gap should be 0.006" to 0-010" for 3hp B & S and 0.010" to 0.014" for 5hp engines. This should be checked at the magnetic bit of the flywheel. Normally you get a good fat spark as you flick the magnet past the coil. You don't with the later, contactless coils, lucky if you can see one but with no points to corrode or points pushrod to stick, they are more reliable and can be retro-fitted, as long as you know what engine you have.
Thanks - I'll try and track down where the cable goes. I'd assumed it just went to a condensor somewhere.
Sorry to be a muppet, but the gap I'm measuring is between the flywheel and the underside of the coil, isn't it? (just need to check that I'm not looking for seperate points anywhere else. I may remove the coil again and give the surfaces all another good clean as I probably only did a three quarter job on them!
Many thanks for the help
-
Yes. The air gap between the magnet on the flywheel and the coil.
-
The points are behind the flywheel, I assumed you had cleaned them and set to 0.020" the condenser is part of the points. Air gap between magnet and coil armature is just that, an air gap, nothing to do with the points.
-
Sorry, don't know your mechanical knowledge, so apologies if I'm over simplifying.
Those engines have the old points and condenser (capacitor) setup. These are behind the flywheel, which needs to be taken off to check/adjust. It sounds like you've been checking the magnet/coil distance which is not the same. If you want to keep the machine, I'd advise taking the coil/points/condenser setup out completely, and instead using the the electronic ignition from a Briggs and Stratton lawnmower engine. You will have a machine that needs less rotational speed to produce a bigger spark (especially noticeable when starting), which doesn't ever (usually) go out of adjustment, so is maintenance free. (second hand part is fine, and not expensive). There is a quick and dirty way to do this which just involves replacing the coil but I would encourage you to do a proper job and take the flywheel off.
You don't really need special tools to get to the points, but you have to go easy because you'll be dealing with (hitting!) aluminium (on the recoil unit) and cast iron (on the flywheel), not the most forgiving of materials.
While you've got the flywheel off, check that the flywheel hasn't moved from its proper position on the shaft (which will affect your spark timing)... The cutout groove on the main shaft and the cutout groove on the inside of the flywheel shaft have a small sacrificial soft metal bar (flywheel key) which locks them together. This should be undamaged and both grooves it fits in should be undamaged. If there is damage it's a faff but repairable (usually). Just means someone hit something hard while rotovating and that little bar took the damage, as it's supposed to do.
If your checking your spark by earthing the spark plug, try with the bare wire instead, resistance on spark plugs builds up over time.
Having said all of that, If I was doing it, the first thing I'd do is take the head off and see if there is any heavy scoring on the cylinder walls.If so, you will either have to spend money remedying it, or live with a poorly performing machine.
I've done this to a couple of these, so if you need more just let me know. There were quite a few videos on YT of what you need to do. Good luck!