Old Briggs 11hp refresh

I did a little assembly work on the engine today:


First I installed the charging/lighting coil (which I had previously cleaned up)...


...and then the flywheel, grass screen and starter cup. Yes I said starter cup because I bought a pull start assembly off eBay for it instead of using a notched pulley as a backup! I'm not sure if I'll run it out to the side as pictured or install a longer rope and put it through the dashboard but I sure am glad the grass screen clears the hole in the fan shroud, it was a bit of a gamble because no size spec was listed for it.


Once it was installed in the tractor I installed the starter, carburetor, engine tin(s) and snugged the head bolts down so the gasket starts to compress. I'll torque the head down next time I'm working on it.


It feels good to have made another step with it, I'm excited to hear it run for the first time since being torn down!

Today I installed the coil, governor linkage and plate then hooked the throttle up.


I also cleaned up and painted the fan shroud...
 



...and I have new stickers that I'll install once the paint has fully cured, they're not exact replicas but they're close and were cheap! Lol.


I'm not far away from firing it for the first time now, I can't wait!

Amazing work! Looks like new

Well... from afar yes... I didn't take the time to sand out all the imperfections but definitely looks better than a half charred motor (it caught fire before I owned it)! Lol

Remember kids…if at first you don’t succeed… two cans of ether!

Time for an official update in the proper thread! Lol.

So the pullstart, intake and a muffler are installed to give it a first fire up...




...and it does absolutely nothing! It only gave one tiny little cough despite having fuel to the cylinder, spark and air

Good thing it didn't start because while attempting to get it going it kind of locked up and I had to turn it counter clockwise to free it up then while turning it clockwise by hand I can feel that something internal isn't quite right so thats a bit of a bummer!

I'll have to open it back up at some point and find out what's going wrong, I was pretty thorough when assembling it and made sure clearances were all within spec. This isn't the first motor I've torn down and refurbished but it is the first time I've had an issue like this so I'll take a step back for now, put another engine in The Warhorse and tackle this engine when I have time to spare or feel motivated to check it out.

That's all for now, I'll update this when I get around to working on it again.

That always sucks, the moment of truth, and then... nothing! Been through that a few times...

Yup but I'm just taking it in stride!

OK, I've been over this thread like 5 times today. The work you did was immaculate. I'm just going to throw out an oddball thing for you because it happened to me once. Pop your flywheel and make sure a magnet didn't fall off. This happened to me 6 years ago. Similar reaction. Would turn backward and had a grind to it when I did.

I would also check your starter to make sure it isn't stuck or sheared, happened to me on a Tecumseh (of course) a couple days ago.

MightyRaze wrote:

OK, I've been over this thread like 5 times today.  The work you did was immaculate.  I'm just going to throw out an oddball thing for you because it happened to me once.  Pop your flywheel and make sure a magnet didn't fall off.  This happened to me 6 years ago.  Similar reaction.  Would turn backward and had a grind to it when I did.

Oh dear what have I started! Lol. Thanks for the kind words and the advice, definitely something to look into and I'll have to remove the flywheel regardless but it should've at least fired so something else isn't right, remember all the metal filings and that I couldn't find a cause? Maybe the reason for that is going to rear it's ugly face! Lol

TechnoChicken wrote:

I would also check your starter to make sure it isn't stuck or sheared, happened to me on a Tecumseh (of course) a couple days ago.

Definitely not the starter but thank you for coming up with ideas I appreciate that y'all have my back! I had the fan shroud off and was turning the flywheel by hand (with the spark plug boot off) so I could see the starter was fully disengaged.

I doubt I'll work on it any time soon as I have so many other thing to accomplish so this thread will probably lay dormant for a bit but after all the work I've done I definitely want to see what kind of jam she has so I WILL get back into it eventually.

Thanks for all the support guys you're the bestest! Lol

Just some food for thought…

I had a flywheel key slide out once when I mounted the flywheel and I didn’t notice. The ignition timing was way off. Just some food for thought.

It may be cam timing though too because I know the frustrating thing about hese briggs is it isn’t always clear which mark is the timing mark

That is good to chew on, guess I'll find out when I remove the flywheel @Rustbucket Garage!  Lol

As for the cam timing... I'm pretty sure I nailed it, someone please correct me if I'm wrong.
 

Welp, I had to move this around today, while it was in my hands I decided it was a good time to put it back on the bench and giver a go...

First I checked the flywheel key a la @Rustbucket Garage and that was all good. Checked the valve clearances and they're good (0.005 Intake/0.0085 exhaust), maybe they're just a hair on the tight side but I can't see a issue there that would prevent it from starting, it did feel like it had decent compression. The crank - cam timing looked to be good so I put the coil back on and spark was a little weak. I cleaned everything back up, set the coil airgap on the tight side (0.010) and gapped the spark plug tight too (0.027). Now that it had pretty decent spark and feels like it's turning over smooth it was time to try a test fire it aaaaaannnd nothing! Not even a cough like what the heck!?

I tore the head off, had a look down the bore and nearly shat myself!


There's no doubt it was scored before but it wasn't that bad there's no way! To be sure I drew it in with a black Sharpie and within 10 seconds of spinning it with the starter it was gone so I knew I had to dive deeper


You guys heard about that new semi-metallic oil going around? Ya me neither!

As some of you may remember I originally tore this motor down because when I took the head off to see what kind of shape the bore was in I found some scoring and several chunks of magnetic crap and that's when I went in looking for the source... and I found nothing... until now!


I definitely inspected everything including the rings and somehow I missed where the oil ring must have had chips out of it, I guess it was hiding! Lol. I've rebuilt several engines (mostly automotive), have a ring compressor and know how to use it so I'm pretty confident it didn't happen upon reassembly because everything went back together smoothly plus this explains where the chunks came from to begin with. I sure do wish I had saved those original pieces to compare against the ring but I do seem to remember them being a darker color metal and probably just thought it was carbon build up. The metal you see floating in that oil is mostly aluminum (from the bore) with a couple flakes of magnetic material I fished out, nothing close to how much I found last go around!

So I'm hoping a 10 thou overbore will be enough to clean it up (I have my doubts) because so far I can only find a genuine B&S in that size, there's no 20 or 30 thou readily available to me aside from Stens.

Luckily I do have a $10 exact replacement short block with a great looking bore/piston and it feels silky smooth so I can transfer all the good stuff over to it if I wanted but heck I put so much time into this block itself and that's what killing me right now! I'm not one to give up on stuff too easily so I need to get this over to a machine shop and see what they think.

Hopefully they don't laugh at me for wanting to save it?! Lol

Do the swap over if you want a good engine now, put the scored block up on the work table and fix'er up at your own pace.

I have considered that so I can get a 1:1 comparison of a completely stock engine to a mildly modified one. Could even put my modified carb on the stock engine to see if all the time I put into it was worthwhile. Could test fit the cam too and as long as I don't need to adjust the valves see what difference if any, there is. I'm not desperate for a motor and won't actually need one for test driving for awhile, if I do I can pull the 14hp Vanguard from the Noma as I won't be needing that tractor until spring cleanup.

It's probably not a bad idea to get the shortblock built, running and tested so I have a good known backup, soon enough I'll have 2 tractors that may need it one day! Lol