B&S 11hp engine question

[handirifle]

OK I checked and the wire that goes from the coil to the ign switch DOES connect at the "M" terminal. It does not show continuity to ground though when the switch is turned off, but as long as it shuts the engine down and does not give 12v I assume it's good?

Thanks all for the education. Now to figure out the erratic running issue(s).

 

[Buckshot 1]

:smile: Even changing the MN: to 252417, did not show up on my list. Trying setting the air gap on the magtron to .012.

 

[Rivets]

Setting the armature air gap to .012 will retard the spark which will delay the spark. I will set the air gap at .009-.010. I'm having trouble with the model numbers you posted. The closest model I can come up with is, 252417-0215-99. Below is a manual for that engine.

http://dl.dropbox.com/u/12502267/B&S Service Manuals/01_270962SingleCylinderLHead.pdf

 

[handirifle]

Well, I already set it at .010" and this thing is set up so that it's kinda a PITA to get to the armature. The battery sits right next to the engine and the battery box is welded in place. I had to cut the welds to remove, and re-welded it :ashamed: so if it has to be adjusted,,, well you get that picture.:laughing:

The good news is, it fired right up! I had gone through the jets and cleared them, and set according to starting specs. Once running I tuned them up to best running, and it runs like a charm.

I did re-do the wiring to the armature though, made it look a little better. There really isn't a great place to run the wire without the possibility of getting it into the rotor, so it goes in the top.

Now to get to those horribly rusted brake lines! Those suckers are REALLY rusted. Most likely they will all have to be replaced.

 

[Buckshot 1]

:smile: handirife, glad to hear you solved the problem. Rivets, I set all of mine to .012 and never had a problem. They all start easy.

 

[reynoldston]

I never knew with the coil air gap a few .001 difference would effect the way a engine would run? I just use a business card and would bet
that no two cards are that close in thickness when it comes to measuring in .001. I am going to make a guess that any where from .006 to .020
isn't going to make much difference on how the engine runs. The only thing it does is change the timing and I don't think by much. I have
never did this, but maybe some day I will take a timing light and play with this and see for myself or has someone did this on this forum done this or knows
for sure??

 

[ILENGINE]

I never knew with the coil air gap a few .001 difference would effect the way a engine would run? I just use a business card and would bet
that no two cards are that close in thickness when it comes to measuring in .001. I am going to make a guess that any where from .006 to .020
isn't going to make much difference on how the engine runs. The only thing it does is change the timing and I don't think by much. I have
never did this, but maybe some day I will take a timing light and play with this and see for myself or has someone did this on this forum done this or knows
for sure??

Had a MTD pusher with the MTD china engine in a couple of years ago that was rope and electric start. It mower would rope start on the first pull, but no matter how much you cranked the engine with the electric it wouldn't start. Didn't matter if the engine was warm or not. The gap is .008-.016. Had to change the gap a thousandth at a time to finally get it to start with the electric. If would start at .012, but not .011 or .013.

Tried changing carbs, ignition modules, making sure the battery was fully charged, but nothing would fix it other than playing with the armature gap.

 

[handirifle]

Had a MTD pusher with the MTD china engine in a couple of years ago that was rope and electric start. It mower would rope start on the first pull, but no matter how much you cranked the engine with the electric it wouldn't start. Didn't matter if the engine was warm or not. The gap is .008-.016. Had to change the gap a thousandth at a time to finally get it to start with the electric. If would start at .012, but not .011 or .013.

Tried changing carbs, ignition modules, making sure the battery was fully charged, but nothing would fix it other than playing with the armature gap.

The manual says the engine must reach a certain RPM (150 if I remember correctly) to start, I assume it's because the coil of the magnatron won't work properly at slower RPM's? Maybe your ecec starter wasn't cranking it fast enough and the rope start was. just a thought.

 

[ILENGINE]

I considered that too, about the starter not turning fast enough. After getting the air gap set at .012, it would start cold, even after setting over night. But wouldn't even restart warm after running before. The mower hasn't been back to the shop since.

 

[reynoldston]

I have never ran across a air gap problim where a few .001s made a difference. Like I said I just use a business card and
I would say no two cards are the same. I can see me now spending spending hours looking for a problim and its just the air gap?
What are you changing when you go from .013 to .011, timing. Then I haven't come across that many Chinese engines.