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Lawnmower Info

W280922B
84698
21302411

Engine
B&S
28b702
1154E1
011009zd

I had it running after I changed the oil and replaced the magneto coil. But now I can pull and pull till my arm is about to fall off. I am about out of ideas. I have looked at the owners manual but it offers very little help aside from telling me to take it to the dealer. I don't think its gas related though because it won't fire even with starting fluid. Gas is new, but could carb be fouled? (it just ran 2 weeks ago). Any ideas?

Thanks for any help.

Brian
 

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First, I would check to see if you have spark first. Take the plug out of the head, set it down on a steel bolt and slowly pull start. If you see a blue spark, then you're gold (and have a different problem). If it intermittently sparks (blue, yellow, white) or none at all, replace the spark plug.

Second, when you replaced the coil, you may have too much gap from the flywheel. That, or the magnet on the flywheel may be rusty. Get your self an index card (3x5 would suffice), place it between the magneto and the flywheel (not against the magnet) and tighten. That should be adequate gapping (this method has never failed me with any briggs).

Finally, if neither of the above work, you may have sheered the flywheel key, thus causing the timing to be off and no spark. Without a puller, this can be a daunting task. My advice, if you get a puller, wrap a chain around the engine block so when it POPS off, it doesn't fly into your face and/or hit you. When you replace the key and put it back together, make sure the flywheel nut/retractable clutch is screwed on and torqued down VERY TIGHT -- otherwise you will have the same problem.

Good luck!
 

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Thanks for the quick reply! I was just working on it. I wasn't getting spark so I was checking wires and it turns out the brake cable had worn the insulation off the wire inside the tubing and was grounding out when brake was set. Wrapped wire with electrical tape and put all back together. Finally getting spark. Now I think its flooded so we'll have to wait a while to try again.

As for the timing/coil situation I gapped the magneto with an index card as you suggested when I installed it, looks like I am on the right track.

I can't believe that the wire and brake cable run in the same location with nothing to prevent this from happening again.
 

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Possibly poor design that was resolved in a newer model. I'd suggest wrapping the wire where it was worn down with extra electrical tape.

You could also go out and purchase small vacuum hose (rubber hose) from any automotive shop, cut a piece 2" or so, cut a sliver long-ways so the wire can be placed inside of it, and electrical tape it in place so it won't slide around. That would provide you with extra protection. I used a similar method to provide extra protection around my front license plate holder on my car from marking up the front plastic bumper. Works like a charm and has lasted for at least 4 years now!

I know it is jerry-rigging, but hey, it works!
 

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This engine is equipped with solid state ignition, CDI.

CDI equipped engine need to turn about 800 rpm to get an acceptable spark.

The proper air gap is .010".

A sheared flywheel key will have absolutely no affect on the quality of spark produced by CDI equipped engine, it will only affect the TIME the spark is produced.

Walt Conner
 

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Thanks guys. Night is falling and my elbow hurts from all the pulling earlier. I am going to have to wait for another day to determine if everything is working.
 

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Found a deal on a Cub Cadet 2130 AGS with bagger and 40" snow blower that I couldn't turn down. Guess you'll find me posting on the CC forum from now on. Thanks for the help. The Snapper was running like a top when the guy came to pick it up. Even if it was tough going for a little while, the next guy will appreciate that it runs!
 

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Others reading these posts guide their decisions partly by what others say here. We all know how discouraging the tiresome act of pulling a pull starter rope can be when it never generates a pop. Obviously, that engine was not fitted with an electric starter. So a fair question is, can a temporary power-starter be reasonably-easily fitted to fire a reluctant-starting vertical crankshaft engine sized like those commonly fitted to Snapper rear engine rider mowers?

Their flywheel's tapered center bore hole is pressed down onto their crankshaft's top tapered diameter by clamping force. That clamping force is generated by a standard "right hand thread" nut. If anti-sieze compound is applied between these two tapered surfaces, they should not lock together so tightly that they cannot later be separated by normal efforts. Yet torque required to spin the engine's crankshaft for starting is MUCH LESS than can safely be applied to that flywheel retaining nut.

I expect you see where I'm going with this. But you say, my trash-deflector screen is installed onto my flywheel. It is appropriate to prevent having air-born grass clipping from being blown by the flywheel fan fins into the engine's cooling system where some of then would eventually clog air flow, causing overheating. Correct. But how about cutting out a small center circle in that screen that's just large enough to allow a deep reach socket to fit onto that flywheel nut so you can power drive your sometimes-reluctant-starting engine without exhausting your body? I don't recall what engine it was that had a removable press-fit cap in its filter screen center, but at least one did exist. It would be nice to retain most of your screen's filtering function while providing access to that flywheel-retaining nut. I saw one which had been used intermittently that had been fitted more than a decade earlier. They just used an electrical box "knock-out plug," which is a little press fit cap that has springy-retainer ears that press into the hole, then expand holding it in place until pried out for service work. If you can make that or a similar small modification, you're well on your way toward creating your own service-mode power starter.

If you elect to do this, it is up to you to work out safety details. It the manual transmission out of gear? Are your feet clear of the prop - or is that blade? Will you spin it with a 1200 rpm electric drill or an air tool?. Do you want a one-way sprague clutch between your starter driving motor and the engine's flywheel nut? Some people are concerned that when their engine fires it can't drive power backwards up the shaft. If you feel that should be a concern, which most people report that is not required, you alone make those final choices.

This is an alternate strategy those with reluctance starting engines can consider. Cost/benefit ratio could be VERY high.
John
 

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B&S recommends installing the flywheel on the crankshaft dry and clean. The use of anti-seize compound is not recommended.

Walt Conner
 

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Walt correctly observed, "B&S recommends installing the flywheel on the crankshaft dry and clean. The use of anti-seize compound is not recommended."

B&S also does not recommend applying crank-spinning torque to start their engines through their flywheel-clamping nuts. In standard clean and dry installations, torque resistance between the flywheel and the crank is supplied through two paths.
1) Their Woodruff key
2) Coefficient of friction between their tapered interfacing surfaces.

My concern was that extra clamping force generated by re-torquing the clamping nut over and over might create so much locking coefficient of friction between their tapered interfacing surfaces that many home mechanics might have a really tough time separating them later. So I elected to sacrifice most of the second torque resistance path to enable easier flywheel removal. I think the Woodruff key is strong enough to lock them together. Perhaps I'm wrong and this would cause Woodruff keys to be sheared off while trying to resist torque without much help from the press-fit tapered shaft in the tapered flywheel hole.
John
 

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"I think the Woodruff key is strong enough to lock them together."

Well don't want to step on anyone but B&S does not utilize a Woodruff Key, only a flat SOFT key which is intended ONLY to align the keyways in flywheel and crankshaft UNTIL the flywheel nut/bolt is tightened to proper torque at which time, in theory, the key could be removed.

Walt Conner
 

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If Briggs & Stratton flywheel keys are so soft that their sheer strength is only high enough to act as an indexing key, we should expect that without significant torque resistance from the tapered press fit between flywheel and crank, those keys would sheer off when loaded with starting torque driven into the flywheel.

I haven't personally tried this so I don't know from my personal experience that it works. But I know someone who told me that he was satisfied using this configuration with anti-seize between the tapered press-fit surfaces. So I assume that he wasn't loosing keys as sheer pins.

Let's try it. Any little slop will definitely cause the key to sheer off from impact loads. I have no ego attachment to the idea that lubrication may be appropriate to reduce excessive locking tendency caused by excess nut-clamping force applied to the crank-to-flywheel taper fit joint.

If it doesn't work, that's good information.
If it works, that's good information.
Presumably crank steel is much harder than key metal, so trial cost should be low. I'm sure Walt has disassembled and repaired many more small engines than I have. I've participated in design and prototyping numerous systems and devices. Let our diversity give us strength. If experience teaches that one of my ideas doesn't work, I abandon it instantly.
John
 

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Tapper fits have amazing holding power when properly installed and torqued. I would point out that the quill to chuck fit of all drill presses of any size are tapper fit.

Also, the intention of the soft key in B&S engines used for push mowers in particular is so it will shear and, hopefully, not further damage the engine if something like a tree root or other obstruction is hit. The engine in question would normally be belt driving something so that is not a factor but here once again, when tightened to the specified torque, the holding power is quit sufficient for the purpose and soft key protection is still present.

Walt Conner
 
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