Coil/magneto Problems? Briggs and Stratton 19.5 HP Twin Cylinder. Replacing the Coil

good morning everyone I should say good afternoon from Jessica Lynch and service so it's just us hanging out at the backyard today me the dogs the chickens and this is the project for the day it's a craftsman riding lawnmower it's one of these dark green ones you've probably seen them around there's a million of them I noticed that the engine isn't quite running the way it should and I'll show you what I mean it starts easy it runs great it idles great but it just doesn't sound right to me and it seems like it's lacking a little bit of power so let's try and figure out what's going on here so if you've never removed one of these hoods there is a trick to it basically just lift it up and you want to disconnect the headlight wire which I've already done and what you do is as you lift it up and pull upwards it comes right off and look at that beautiful Briggs & Stratton engine I have the heat shields removed on both sides the shields that go over the cylinder heads actually it came in that way but let me show you how it runs sounds good right watch that in change did it so it will run on one cylinder that's what's going on actually so one of the ways that help me determine that it was a coil that was going bad or more specifically it was the cylinder here that wasn't functioning was that I got the motor running for a while and I reached down and I felt the exhaust manifolds and the exhaust manifold on this side was red-hot couldn't even touch it the exhaust manifold over here was was pretty cold so that told me right there that this cylinder wasn't creating combustion wasn't creating heat to go at this exhaust pipe here so that's how I determined that that cylinder wasn't functioning correctly and I checked for spark and I saw no spark and I'll show you how I did that it's got to make sure that the spark plug wire isn't all rusted out so you have a good connection with the spark plug this is a brand new spark plug by the way and I basically just wedged it right up here where it would stay and would be grounded because you have to ground the spark plug to test it out okay so you want to make sure you ground the sparkplug to a nice piece of metal not aluminum but a good solid metal bolt on the engine and when you turn the engine over you should see spark at the spark plug there which I didn't so that's why I wasn't afraid to grab that spark plug wire I'm going to turn the engine over so you can watch for yourself to see if you could see sparking no spark so we know that most likely we have a coil that's bad so to do that you need to take off this cover here and as I said I've already removed the heat shields on both sides you have a couple bolts here and a couple bolts on this side to remove those covers but you don't need to remove those covers to lift off this top red cover what you need to keep in mind is that you have your oil dipstick attached to this cover alright so we need a coil think I know our ones that just go marching into the jungle here lawnmower jungle that is and boom that's my victim right there I believe we have a good coil on this engine so let's pull it what do you think everybody yeah that's good don't need that so it's got a 5/16 but I'll loosen up this dipstick with I probably will end up putting these shrouds on to back on this other engine because those shrouds actually aid in cooling to the clean of cylinders so they're pretty important to have on there it's an air-cooled engine and that air circulation is what cools each side these covers help keep that air circulating around so this is the bracket that holds the oil dipstick on and once again there's I think I've already taken the 3/8 bolt out of this side and I've also taken it out from behind here this is for that other engine I stole these parts for already it looks like that one's almost gone so yeah you have a bolt under here right under here 3/8 back here here and under here take these bolts off on each side here all right so that's good enough for me to get this coil off here there it is that's what we're going for there's two 5/16 bolts on there but I can't get them off I need to go get a socket I hope this coil is still good let's take this sucker off of there okay so all you have to do is disconnect the keel wire on the bottom of the coil and that just pulls right off with a little bit of effort there we go and disconnect the wires from the spark plugs and should be able to pull it through pretty narrow passageways these wires have to come through all right okay so here's our first look at this thing looks like it's in decent shape sort of but I think it works so let's test it out there we go Wow and there's the coil so the gap between the coil and the flywheel magnets is 0.001 two inches disconnect the grounding wire sometimes you have to pry it off of there oh there we go let's get these spark plug wires on tangled here you can just bend up this cover to get the wires to come through okay help me remember this bad coil good coil help me remember this bad coil good coil bad coil good coil bad coil [Applause] does matter which way you put the coil so make sure you put it back the way you took it off so the screws off of the salvaged motor we're in a little better shape than the screws off of this motor so we're going to use these now we just lightly snug them down so you can still move coil alright time to gap this though so you see that gap right there that's the gap is a C those are the magnets on the flywheel right here and is that as they go past the coil that's what generates the spark or the magneto set this side first not fully tight yet just enough to confirm the measurement needs to be opened a bit it's kind of tough to get that measurement to because it's curved but just do the best you can sometimes I'll just put the feeler gauge in there like that and tap on the coil I think that's pretty good on one under this one okay I'm going to tighten them both down are not too tight because these bolts are very easy to break and you'll be hating life if you break them both are tight time to double check because quite often when you tighten down it readjusts for you I think we're a little tight on this side still so I'm going to readjust that I think that's going to work alright time to reconnect spark plug wires and test this baby out [Music] just poke the wires right under there actually which one is which assume the long wires what goes to the other side yeah so this is the long one here a little rusty in there I don't know if you can see that so I'll make sure to clean that out with a file or some sandpaper first make sure you don't pinch these cables in there there's a little slot that they go through I think I'm going to leave this cover off just to test it out see how it runs that's just going to run perfect now yes I can tell it's running on both cylinders now it sounds a lot smoother and here we'd be able to tell a difference if I remove the spark plug wires yep [Applause] you [Music] [Music] [Music] you [Music] [Music]

Channel: Jeff's Little Engine Service

Views: 612,675

Rating: 4.5642161 out of 5

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Id: 46DxITAV_NQ

Length: 17min 46sec (1066 seconds)

Published: Sun Jun 18 2017