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-   -   Generator Spark Plug: No Fire. Why? (https://www.askmehelpdesk.com/showthread.php?t=387921)

  • Aug 17, 2009, 07:32 PM
    Jennings3
    Generator Spark Plug: No Fire. Why?
    It will only fire when the paddle of the kill switch is disconnected. Does that mean that the coil is bad? What is causing that?
    Homelite RE440 with a B & S 197417 motor with electric start. It was abused by my stepfather and I thought I'd try to make it run again. Many thanks, Jennings3
  • Aug 17, 2009, 07:37 PM
    Stratmando

    That Paddle shorts the ignition(a kill switch), It needs to be disconnected to run.
    I also wouldn't keep cranking it while closed/shorted, It can't be good for the coil, may not be bad.
    I would also do a Tune up(Plugs, Air Filter, Oil, Fuel Filter at the least).
  • Aug 17, 2009, 08:17 PM
    Jennings3
    So, this means that when the ignition is shorted it fires the plug? But when it is not shorted the plug will not fire. Does that mean that the magneto/coil is bad and needs preplacement?
  • Aug 17, 2009, 08:44 PM
    crigby

    Hi,
    That is backwards; the ignition shorted to ground is what cuts it off. When there is no path to ground, the ignition works and the plug fires. If it does not work, then the switch could well be bad. But you also need to ascertain whether there is an Oil Gard low oil shutoff present (often is on generators) and connected into the same circuit as this will give the same indication with a low oil situation.
    Peace,
    Clarke
  • Aug 18, 2009, 05:56 AM
    Stratmando

    If you know it fires when the paddle is off plug, may be a fuel problem, why do you think the coil is bad, it fires?
    Got any Starting Fluid, this will tell If it is a fuel problem. If It wants to run with starting fluid, it is a fuel problem.
    Don't overdo starting fluid. Carb may be dirty as well. How does the plug look?
    If you can't do a tune up at least check the plug and Air filter.
  • Aug 20, 2009, 09:49 AM
    Jennings3
    Thanks for your responses:
    I tried starting fluid, no luck, no spark, except when the kill switch is disconnected. Now, when the engine turns over it makes a loud shriek, squeak on each turn. Like a brake is on or something. There is plenty of oil.
    Dropped the bowl and cleaned the float and things that were accesible. There is gas flowing out of the carbureator.
    There is continuity between the oil kill terminal and ground. There is continuity between the oil kill wire and ground.
    Any ideas? Thanks, jennings3
  • Aug 20, 2009, 09:55 AM
    KISS

    The squeeling is due to the clutch in the rope starter. Take off the blower housing and then the clutch.

    You can CAREFULLY take it apart. There are about 5 balls in the usual design. Don't loose them. You nned to clean it. No dirt or grease here. The part is about $12 if you go the replace route.
  • Aug 20, 2009, 09:57 AM
    crigby

    Hi,
    It is the starter clutch that must be replaced or cleaned and lubed to cure the shriek. Rope "jump" around, also?
    You have an unwanted ground/short electrically, be it in the switch or wiring. It is unusual but you may have a stuck or bad Oil Gard. It can be disconnected, but that means you must replace its diligence about oil level with your own.
    Peace,
    Clarke
  • Aug 20, 2009, 11:37 AM
    Jennings3

    I will do what you suggested. While I have the blower housing off and can access the coil, can you tell me how to test it? Thanks, jennings3
  • Aug 20, 2009, 11:54 AM
    crigby

    Hi,
    I would not see the point if you have fire when the switch is diconnected; it works. Check the wire for bare spots that create the short.
    Peace,
    Clarke
  • Aug 20, 2009, 12:00 PM
    KISS

    The top post suggests a bad kill switch. That makes a lot of sense. It's stuck closed.

    The squeakyness is easily fixed. It's going to be hard to start with the clutch squeaking. What happens is the motor grabs occasionally when running. It's almost like a dead stop.


    You have to fix the clutch first.

    Coil testing is usually done with a special tester so you can observe the spark. It's kind of like 2 plugs in series.

    Make sure the gap is OK and the blower is free of rust along the magnets. I'll assume no points.
  • Aug 26, 2009, 07:26 PM
    medic-dan

    Have you had any luck?

    Continuity between the oil kill and ground = no spark.

    I'm not sure what you mean by paddle on the switch. Do you mean the terminal? If so, disconnect just the oil kill circuit and test for spark. It sounds like the oil kill switch failed, very common.
  • Apr 8, 2012, 05:58 PM
    Jennings3
    I disconnected the oil gard wire. With starter fluid sprayed in the carburetor all I got was one back fire.

    The thing still chirps when turning over, even with the blower housing and rewind/starter rope removed.
  • Apr 8, 2012, 06:25 PM
    medic-dan
    Well, you've likely got a spark then.

    Do you have compression?

    Where is the chirping coming from? Which end of the engine?
  • Apr 9, 2012, 07:48 AM
    Jennings3
    Hey thanks: It was just one backfire on many turns. How check compression? It is difficult to tell but the chirp seems like it is from the side with the exhaust and the carburetor.
  • Apr 9, 2012, 09:01 AM
    medic-dan
    It can be hard to check compression. Some of the small engines have a compression release feature to make it easy to start. I don't know if your engine does or not.

    Basically, you get a compression tester and screw it into the spark plug port. Then with the throttle and choke both wide open you pull the cord. It should build up pressure. The alternate method is, do you feel any resistance pulling the cord?

    I'm not too worried about the chirp. It may just be air moving in and out
  • Apr 9, 2012, 11:24 AM
    Jennings3
    The chirp/shriek is very loud. It sounds more a mechanical sound as opposed to air moving. I really can't isolate the origin of the noise.

    Pulling the starter yields little resistance. I could not find info regarding pressure release feature.
  • Apr 9, 2012, 11:33 AM
    medic-dan
    Can you pull they cylinder head off? It shouldn't be very difficult on a flat head. Just be careful with the gasket.

    Then, turn the engine over and watch the operation of the valves.
  • Apr 9, 2012, 11:39 AM
    Jennings3
    Man, I've always wanted to do something like that! I might try but hope my wife doesn't catch me; supposed to be looking for a job; laid off. Thanks for the advice--
  • Apr 9, 2012, 02:49 PM
    Jennings3
    Removed the cylinder head; it is black with a little rust in places.

    The piston is black but the cylinder is smooth except at the very top and where there is a bit of rust.

    The valves are black, seem intact, and move in rhythm.

    With the removal of the head there is no longer a chirp.
  • Apr 9, 2012, 04:14 PM
    medic-dan
    That's good. It's not likely to be a mechanical problem making the chirp then. Sometimes they can make a noise "breathing." I have one that "whoops."

    If you want you can check for spark now. It should be very easy to spin. I do think you have a spark since you say it backfired once.

    That ridge at the top of the cylinder is normal.

    Put the head back on. If you can, torque the head bolts to 190 inch pounds. Otherwise snug but don't lay on them.

    It is very likely a carb problem. They're pretty common on a generator as they tend to sit with fuel in them then it gums up. That engine should have a float type carb. You'll see a float bowl under the carb.

    How's the fuel? Is it clean? Disconnect the fuel line from the tank and make sure what comes out is clean and fresh. If it smells like bad (stale) gas, get rid of it.

    When you're ready we can look at the carb.
  • Apr 9, 2012, 08:02 PM
    Jennings3
    It sparked pretty good, even with the oil sensor connected.

    A one inch piece of the gasket came off when head pulled; guess the whole gasket needs replacing, no?

    The fuel was old. I drained the tank, rinsed with gas and then again with a little bit of acetone. Tank still mounted to the frame, so I rocked the generator a bit to swish.

    Sprayed the carb with carb cleaner. Added fresh gas and it started leaking and dripped from the bottom of the carb bowl.
  • Apr 9, 2012, 09:25 PM
    medic-dan
    You'll need to replace that gasket then. It shouldn't be that expensive. Take the old one with you and the engine model/serial number. Clean off any of the old gasket before putting the new one on. Don't scratch the mating surface.

    At least we know you have a good spark.

    I'd take the carb off and clean it thoroughly. If you go this route take pictures of ALL the linkages before you do. There's nothing worse than not remembering how to put them back on.

    It might be easier to just pull the float bowl and clean it out. Carefully remove the nut on the bottom of the float bowl with a wrench. You shouldn't have to turn the needle valve (if it's adjustable). Make sure the float moves freely, be gentle with it. Fuel should come out when the float is down. Be careful lifting it. There's a tab on the float that can bend.

    If you feel really ambitious there is also a jet (nozzle) that you should clean. If you look "up" into where the needle valve assembly you should see it. You can remove it with a flat head screwdriver. Clean it out with some carb cleaner and spray into the opening where it came out of.

    When you get done reassemble it.

    Give it a try.
  • Apr 10, 2012, 02:31 PM
    Jennings3
    These carb mounting studs have some sort of hex head. They look just a torx wrench on the end. Must I find a hex socket, better not jump on it with vice grips?
  • Apr 10, 2012, 02:45 PM
    medic-dan
    Find the right tool. It makes it much easier to do the job correctly.

    Remember to take pictures. The governor linkage especially on a generator is VERY critical to the proper operation.

    I usually disassemble the carb on a "baking sheet." That way any parts don't go very far.

    Take your time getting it off. If you can soak the carb in parts cleaner great. If not, even hot water and soap won't hurt. Compressed air to blow out all the orifices is great too. Then make sure you have clean fuel (I know you did the tank) all the way throughout the fuel line, no junk, before you put it back together.

    Good luck.
  • Apr 10, 2012, 05:57 PM
    crigby
    Ji
    T-30 Torx will do it, I think(if I remember right.)
    Peace,
    Clarke
  • Apr 11, 2012, 08:16 AM
    Jennings3
    It seems that the condition of the generator end is important and the rings and pistons. Before going too far, how can I determine if this machine is salvageable? Many thanks--
  • Apr 11, 2012, 08:21 AM
    medic-dan
    So far, from what you said, the engine is in good shape. You said the bore was clean, a bit of a ridge is normal. If there were no big scratches on the cylinder it should fire. Can't say about using oil, until you get it running.

    It's the same with the generator section. You could check all the wiring, etc, but really can't do much without it running to tell what will happen. Sometimes, if they sit for a while, they can lose "residual" magnetism and won't make power - at first. There are some tricks to get past that and get it making power again.

    So far, except for that gasket and some carb cleaner you likely aren't investing that much.
  • Apr 11, 2012, 09:27 AM
    Jennings3
    The carbon on the cylinder top comes off with gentle scrape of putty knife. What about removing that and the carbon on the valves?
  • Apr 11, 2012, 09:34 AM
    medic-dan
    Go for it. There's no problem cleaning it up.

    It sounds like it had been running in good condition. Some carbon buildup is normal.
  • Apr 12, 2012, 11:25 AM
    Jennings3
    Do the fuel lines need to be cleaned? Just spray cleaner into them?

    How best deal with that little fuel pump? Is it okay to spray cleaner into it?

    Thanks--
  • Apr 12, 2012, 05:46 PM
    medic-dan
    You can spray cleaner in them or run some gas through them. Whatever is easier.

    What fuel pump? Describe it or if you can, post a picture. Usually they are "gravity" fed from the tank to the float bowl.

    I can't find your generator to look up. Do you have a better model number?
  • Apr 12, 2012, 07:56 PM
    Jennings3
    That's the model number in the link to the parts diagram pdf: 197417-1143-E1. It is beside the carb attached to the engine: http://www.briggsandstratton.com/sup...197417-1143-E1
  • Apr 12, 2012, 08:13 PM
    medic-dan
    Yup, you have a fuel pump. It may have failed.

    Briggs tells you how to "service" it. Here: http://http://www.briggsandstratton....20fuel%20pump/
  • Apr 14, 2012, 12:59 PM
    Jennings3
    That is a really good resource, many thanks. I cleaned the fuel pump as directed, quite gummy.

    Local dealer did not have the carb gasket so I ordered it on line.

    Well, the fuel line that runs close to the exhaust is cracked pretty good. I got some cut to order.

    The inner diameter is the same but new one is not as thick as the old (will get smaller clamps).

    Is it okay to use the fuel line with thinner walls close to the exhaust?
  • Apr 14, 2012, 06:06 PM
    medic-dan
    Glad the link helped you out.

    I'd keep it as far from the exhaust as you can but there isn't much else you can do. Yeah, the clamps they use won't fit "generic" tubing.
  • Apr 24, 2012, 09:32 AM
    Jennings3
    The oil is 4 years old but the engine has never been started. Does it make sense to crank it (if it will start), let it warm, then change the oil or should I change the oil before turning it over?

    What about lubing the cylinder before attempting to crank? Should a little oil be put in there since it was cleaned with carb cleaner and is dry of lubricant?

    Also, does anyone know the torque specs for the carb gasket AND the air cleaner gasket on the Briggs/Stratton Engine 197417-1143-E1 Code: 990506YD (8 HP generator engine)?

    It does not seem to be available on line.

    Much thanks--
  • Apr 24, 2012, 09:41 AM
    medic-dan
    It wouldn't hurt to put say a teaspoon of oil down the spark plug hole then pull the engine through a few times, plug out, to distribute the oil. Then put it back together.

    If the oil is clean, you could fire it up then change it. It will be much easier to change when warm. I don't think a short run with clean, old, oil will hurt it.

    I don't have those specs in my Chiltons book. I'd just tighten them until snug, don't crank on them.
  • Apr 24, 2012, 11:07 AM
    Jennings3
    With that news I'll put her together this afternoon and give the old gal a yank (actually there's an electric starter).
  • Apr 25, 2012, 06:30 PM
    Jennings3
    She ran for about a minute then stopped. Fuel is leaking out of the mouth of the carb. What might be the cause of that?

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