B&S 11.5HP Riding Mower sitting for 2 years+ where to start...?

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HusqyStihl

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Took this on as a charity project in an attempt to fire-up a MTD Tard Machine with a B&S 11.5HP motor. Low income family but very very nice people and have been pricing parts (thanks to Jacks Small Engine exapanded IPL's (click and add to cart).

History behind the mower: The neighbor purchased it 3rd hand and run it either one or two summers and then the third summer is under a no-start situation. I love to do people favors or charity work because the word spreads and brings in other customers. Things been under a lean-to for the past two years and covered with a tarp. Thats all the info i could get from the lady. EDIT: besides "the alternator doesnt charge the battery"~neighbor (they don't have a clue how to work on these things but said they'de love to learn how). I myself is not what you'd call a ride-on mechanic but ive fixed everything from chainsaws to Heavy Equipment and Tri-Axle Rigs.

First thing was to check the battery, which was damn near empty so i filled with distilled and set it on my smart charger/jumper over night and 3 times it read bad battery, i usually give it 4 or 5 chances while unhooking it and re-applying the cables and starting over. 3rd time failure and i'm losing hope. The neighbors dont have alot of money so i'm doing it on the cheap as i can before digging deeper. If its a no go what-so-ever, the machine is mine anyway but i dont plan on dropping a couple hundred bucks so they can go from 3/4's of an acre with a push job to full ride-on.

Checked gas tank, bone dry. Added some fuel and discovered crazked open (dry-rot) fuel line between the fuel filter and carb. cut as much line off as i could and threw in an upgraded see thru larger fuel filter in replacement of the old "flying saucer" or "disk filter" which in my opinion such. Also allowed me to extend the fuel line because it was longer than the stock filter so good for no more leaks.

Air filter looks in great shape. Starter top gear that engages is mangled but entire top kit comes from Jacks at $21 and change, not too bad.

If the battery won't hold or is declared dead completely, is there another way to try to crank it over? My "smart charger" has the option to jump also but seems to do nothing when applied. Its the kind that has to sense it's hooked up prior to doing anything on its own. Will a 12v jump aid in trying to get it to at least turn over? as i do not wish to spend on another new battery just to find out that the internals are fried on a charity case and end up with a scrapper and nothing else to do with thenew 6v.

Can't check for spark until i get it turning (unfortunately its an electric start only) until i get crankin. I've got an assortment of plugs if needed so i'm not worried about that. Also have a chainsaw comp tester and an Automotive comp tester. Which to use? It's a 4-stroke. but again, i gotta get it to crank to proceed.

Carburator cleaner used the best i could throughout the carb and down the throat, i'm hoping its an "ethanol over the winter thing"..

Throwing parts at it is not the way i wanna go, and if it was, i'm keeping it. Also needs tires, at least on the front and prob the back from dryrot and sitting in the same place for years. And will need a good pressure washing.

I feel bad with them struggling (usually the wife cause the husdband works) but it would be much easier for him to push mow once a week instead of once a month.

I guess the question is, how far would you get into a project like this (as a charity job for a neighbor) before calling it quits.

Any other cheapo stuff i can attempt or check over to rule out any internal damage without full disassembly? Next couple steps from here?

Or pull it and hold it for a decent splitter motor? My fathers got a splitter with 12hp motor, could work on a 27 ton no?
 
Try jumping it with your car. An automobile battery should work just fine to turn it over. Don't bother with compression test they have compression releases so you will get a low/false reading. Check fuses and connections for charging problem.
 
Danger, if this has the electric fuel valve on the bottom of the carb, they will not seal well after setting and the cylinder will hydrolock. You can break a piston under this condition, pull the plug and wrap tape around the plug wire keeping it where it can't cause a spark and then turn the motor over. It may not be the battery, it might be that the motor can't turn.
 
Danger, if this has the electric fuel valve on the bottom of the carb, they will not seal well after setting and the cylinder will hydrolock. You can break a piston under this condition, pull the plug and wrap tape around the plug wire keeping it where it can't cause a spark and then turn the motor over. It may not be the battery, it might be that the motor can't turn.


The battery had little but very very low water in it to begin with, so i filled with distilled and started charging from there to see if it could be brought back to life. It seems to be holding at around 80% last time i check this afternoon in the shop.
 
Quick question, Jacks Small Eng show their "Briggs" part number for the engine but no cross reference. Any way to find out exactly what cross-refernce plug i could find for it? ive been all over the net trying to find a suitable replacement or 2 just to rule out any spark issues and also i'd plan to use the in-line spark tester..
 
IMG_0429.jpg

still trying to cross reference...

Another thing, wouldn't jumping it with 12volts from a car battery put a really hard strain on the "god knows hold old" starter and assembly? i'd hate to blow something that just adds to the list of whats already shot...
 
Danger, if this has the electric fuel valve on the bottom of the carb, they will not seal well after setting and the cylinder will hydrolock. You can break a piston under this condition, pull the plug and wrap tape around the plug wire keeping it where it can't cause a spark and then turn the motor over. It may not be the battery, it might be that the motor can't turn.

if i get that far, i do plan on turning it over after pulling the plg completely and airblasting the inside of the cylinder a couple of times to get anything i can out including old fuel. then i plan on spraying 2-stroke oil in there with the help of compressed air just to minimize the chance of a dry start-up and the negative affects. better safe than sorry
 
Try jumping it with your car. An automobile battery should work just fine to turn it over. Don't bother with compression test they have compression releases so you will get a low/false reading. Check fuses and connections for charging problem.

Ive already checked all fuses as far as i've found and will continue to check. I have no problem turning it over with 12v and thats exactly what my "smart charger" should do in either 6 or 12v but doesnt wanna do anything until it sees its connected at all. There was the correct ammount of oil in it so i'm thinking dry-sieze from no oil is a rule out. But sitting for so long, ya never know. we shall see. unfortunetly nothing but rain the next couple days and the shop is full of paying customers first
 
Car battery will be fine.

J19LM Champion is the plug you need. Or Auto lite 308 I think? Sorry, not sure on other brands, we mostly use Champion.. the J19 for sure is correct. Ultra common plug used since the 80s on small engines.
 
Car battery will be fine.

J19LM Champion is the plug you need. Or Auto lite 308 I think? Sorry, not sure on other brands, we mostly use Champion.. the J19 for sure is correct. Ultra common plug used since the 80s on small engines.

Nice! i've got plenty new J19LM's in stock. Thanks for that, no need to look around for a new one or order one for 3$ and 10$ shipping. Apreciate the response sir!!

I run mostly Champion anyway and have never had a problem, even eyeing up the gap withuot useing my gapper and always fires dead on and never once had a failure of any kind!

~Moose
 
Not yet mentioned is the key in the flywheel shaft.

You can get spark, fuel, etc. and still wont start is the key is even partially sheared. Also check timing.

I have bought a lot of old engine stuff including mowers at garage sales, surprising how many shaft keys are partially sheared. Less common on belt driven mowers though.
 
PS: you knew this, but the key can be checked by just removing the flywheel nut and looking at the keyway alignment between shaft and flywheel, no need to pull flywheel.
 
WalMart has batteries for 19 bucks now. If it has fuel, spark ( magneto is likely good ) and compression. It will run. Adjust the valves. They have a mechanical compression release that if the valves are tight will not release. I bet that's what is wrong. Common no start condition on them.. My guess is it needs a battery and the Bendix drive for the starter. Napa also has the parts too.
 
You can get spark, fuel, etc. and still wont start is the key is even partially sheared. Also check timing.

Perhaps, but I stand by my advice to check the 3 most basic necessities first.
If timing is all chitted up because of a sheared key, it's obviously going to cause problems. I'm not a small engine guy, but I suppose if a quick visual check can confirm or rule out, by all means check it out.
PS-as long as timing is close, a motor will "pop" (but only if you have the 3 basics listed above :)
Ok-stepping down of my soapbox.
 
WalMart has batteries for 19 bucks now. If it has fuel, spark ( magneto is likely good ) and compression. It will run. Adjust the valves. They have a mechanical compression release that if the valves are tight will not release. I bet that's what is wrong. Common no start condition on them.. My guess is it needs a battery and the Bendix drive for the starter. Napa also has the parts too.

I threw out a rough guestimate on battery replacement, figured around 20$ or so. If this battery fails thats the plan. But gotta get her crankin before i figure out if its seized or not
 
you should be able to turn it over by hand from the flywheel grate
 
WalMart has batteries for 19 bucks now. If it has fuel, spark ( magneto is likely good ) and compression. It will run. Adjust the valves. They have a mechanical compression release that if the valves are tight will not release. I bet that's what is wrong. Common no start condition on them.. My guess is it needs a battery and the Bendix drive for the starter. Napa also has the parts too.

May i ask what a bendix drive is? And how to go about the tightened valves? Looks like ill be tearing it down a little more to check things out. Figured the old "ran fine last summer" makes it a ethanol sabbotaged problem. Carb gunked but after finding the junk fuel hoses, i knew there was alot more to it..
 
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