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7/9/2025
Roberto N. Underwood
2020/10/09 14:30:55
JacksonRobertson

Picked up an old bug infested mower from a local hoarder - think we can get it running?

By we I mean the collective might of this forum.  I could dump it but I figured why not have a new project to start to see if we can get it all going again for the fun of it.
 
Here's the video tour (just pretend your name is Cody):
 
https://drive.google.com/file/d/1VOHbWoPnpFnA74MS94vAR_hSamjdf0EX/view?usp=sharing
 
Also it's upside down for some reason, so thats cool. 
 
I took a closer look at the pull start, the thing really does not want to move much:
 
https://imgur.com/u8CzbMQ  (it has audio)
 
I took off the air filter cover, there was no air filter, so I am going to need a new one of those. Also, I think it has an ant infestation, so I am going to need to hit it with a flamethrower to get rid of those.
 
So, besides putting it out on the curb for someone else to take this trash off my hands, where should we start to see if we can bring it back to life?  Right now I see the pull cord and the tension wire for the engine cut off being some major issues.  The pull cord can hardly move right now as you can see on the second video.  
 
Time to learn!  If we can get it fixed and I can sell it for more than I spent in parts I'll buy everyone a diet beverage (no ice) next time you are in town.
15 comments Leave a comment
Roy
Can you give us the make and model of the engine? That would really help with diagnosis of the problems. How much oil? Is it thick and black? Tip the machine on its side and have a look at the blade and shaft. If the shaft is bent put it back on the scrap and walk away.
2020/10/09 15:57:11
JacksonRobertson
Oil: Not sludge yet, its black but it still has some viscosity left in it.  Obviously needs to be changed.  
 
Fuel tank is bone dry.
 
Engine, took some pcitures if these help. having a rough time reading the numbers but the first set looks like "160602"?
 

 

 

 
Went under and took off the blade:
 

 

 

 
Its straight and it spins, not easily, but spins, and the engine bits up above (I should learn the terms) also spin so the connection is secure from the engine down to the shaft.
2020/10/09 17:02:19
JacksonRobertson
tl;dr: the fuel tank leaks
 
Okay, update:
 
I have since taken out the spark plug and shot everything with carb cleaner and wd-40.  Once the spark plug was out the cord pulled smoothly.  Oil also was dumped out, about a shot glass' worth came out.  Filled it all back up with full synthetic. 
 
Check this out!  https://imgur.com/a/bWEPc5n
 
Compared to what we were working with before, this is a totally different world.
 
I also went ahead and swapped out the fuel line, it was grungy and rotting.  No air filter yet.  Also took a look at the spark plug, not the prettiest thing in the world:
 

 
I put everything back together, added some SeaFoam, put in some gas, gave it a tug.  Nothing started but I got a puff of black smoke out of this thing:
 

 
At least something was happening.  Walked back around to look at the fuel line.
 
Oh no.
 
The fuel tank is leaking like a sieve.  I opened it up and added some more in.  It came right out the bottom.  
 
I think I see a replacement online, its 35 bucks though.  This was an unexpected and sad development. 
2020/10/09 19:02:30
Roy
That machine has been sadly neglected. For one thing the motor will not turn over easily because the blade is missing, it is part of the flywheel system. Remove the cylinder head and check the walls for scoring or galling, if that is present the engine is junk. The first characters are 12 which indicate the engine displacement. The next one is a letter or number.
2020/10/09 19:07:22
JacksonRobertson
Oh, the blade, I took that off to check the shaft, I have it sitting in the corner of the garage, I can put it back on tomorrow.
 
How do I remove a cylinder head?
2020/10/09 19:40:55
kshansen
I personally would take some fine sandpaper to those numbers to make reading them easier. 
Then maybe head over to:
https://www.briggsandstratton.com/na/en_us/support/manuals.html?icid=homepageredesign_manuals_icon#
 
And see if you can find manuals for the engine.
 
But yes on a rotary push mower the blade is important for the flywheel effect it gives. 
 
Maybe the next thing I would be checking is does it have good spark, if you mentioned this I missed it.
 
Then I would want to know if it has compression. A leak down test would be great but just a good feel while spinning over with starter cable should tell you that much.
 
If all that checks out I would be considering cleaning the carb. But that takes a bit of careful work and a good place to work especially if it's your first time doing it! 
 
As a side note to this I could never understand how someone could let a mower get so bad from neglect. But then I could say I'm glad there are people like that, see I have only bought one in the last 50+ years. That one was abused mowing what was a cornfield to be our lawn. Bent the crank but did still run when I gave it away. Since then I have given a few away and even sold one and right now I have two that are good to go with one or two tuggs on the rope! 
2020/10/12 08:12:15
JacksonRobertson
kshansen
Maybe the next thing I would be checking is does it have good spark, if you mentioned this I missed it.
 
Then I would want to know if it has compression. A leak down test would be great but just a good feel while spinning over with starter cable should tell you that much.
 
If all that checks out I would be considering cleaning the carb. But that takes a bit of careful work and a good place to work especially if it's your first time doing it! 



Hi!
For the spark, I picked up a spark plug detector/tester yesterday from Harbor Freight so I will be able to use that to test.  Also when wandering around the automotive section of WalMart I found a replacement spark plug for $2, so I should be able to use that one once everything is put back together.
 
What's a leak down test?  I have never heard of that.
 
For the carb, I think I am just going to take it all apart because I never have before and as this thing is from basically the scrap pile anyway I am not worried about screwing anything up as I got it to learn on.  I know it's a bowl type carb and have seen a few cleaning videos online, might as well figure it out on this hunk of junk so if I ever need to do it on something that actually has some value at least I will have experience!
 
For other updates:
 
I have put the blade back on the mower, its as rusty as everything else in the pictures but its back on there now.
 
I put JB Weld on the gas tank after taking it off and scrubbing the cracks clean.  It's been curing for 18 hours and when I tested it today it holds water, should be good to go for gas once I get it hooked back up.
2020/10/12 09:20:48
Roy
Run a quick compression test by tying the bail down then with the spark plug disconnected flip the blade backwards. If the compression is good the blade should bounce back.
2020/10/12 13:01:26
JacksonRobertson
I took the suggestion to sand down the number on the engine and I think we have a victory:
 

 
Engine # 12J802-2915-B2
 
I went ahead and removed the carb so I could futz around with it.  The bottom bolt is sealed on there.
 

 
It's a 1/2 nut but was so tight the socket wrench stripped it just enough that now it spins around.  I tried using a regular wrench but that's not having it move either.  It's currently out there soaking in liquid wrench in hopes something will work.
 
I found two numbers stamped on the carb: 
 

 

 
8823
 
224806
 
If I cant get the bolt off will any of these numbers help everyone source a replacement?  
 
I have not yet done the blade compression test, got too annoyed at that bolt to keep going.  Also the tension cord that holds the bail to the engine is also busted.  So thats a step as well.
2020/10/12 15:58:51
JacksonRobertson
New video!
 
I got the bolt off the carb after a two hour liquid wrench bath.  Sprayed about a can of carb cleaner on and in and through everything, put it all back on.  I did something wrong with the choke lever as its not working and I cannot at all right now figure out how I attached it wrong.  I put it back on how I thought it looked in the picture when I took it all off.
 
Here's the dirty before picture showing how its hooked in on the right most hole on the carb:
 

 
And here is the video of it cleaned up and reattached.  The lever isn't moving the value, its only staying open.
 
  https://www.youtube.com/watch?v=8MZB9pdYMtA

 
Thoughts?
2020/10/12 20:03:18
kshansen
Can't help with the link for the carb but this might be of some help, a link to where you can download a parts book on this motor:
 
https://www.briggsandstratton.com/na/en_us/support/results.multiStepManualSearch.html?searchrequested=12J802-2915-B2
 
Just click on the read box to the right side of the line where it says "Illustrated Parts List"
2020/10/13 09:25:32
AVB
That is not the choke but is the throttle vane.The governor spring should be pulling it to wide open when the engine not running.
 
You got a primer setup. Note that the air cleaner base do tend to warp requiring a modified gasket setup to get the primer to work.
 
EDITed for missing wording.
2020/10/13 10:43:30
JacksonRobertson
Okay for a few new updates..
 
Did the compression test thing, held the bail down and pulled the cord, the blade moved as I did that.
 
New spark plug also added in and I used the spark plug detector and it glowed orange, so we are good there too.
 
Since the carb appears to be working then as expected, I left that alone too.  It's indeed wide open with the engine not running so that is also okay now.
 
Gas tank has been hooked up, new fuel line connected, and using screw down clamps now instead of the clip on kind.
 
So really, at this point its time to put gas back in again and see what happens?
2020/10/13 14:24:52
JacksonRobertson
IT RUNS!  I GOT IT TO START!!!
 
I have the carb cleaned, the gas tank patched, and more. It now starts after a few pulls and the blade spins and everything works as it should for cutting grass. All except the muffler which blows non stop white smoke out and gasses out the entire street.
 
Photo: https://imgur.com/a/Mr3nybc
Video: https://www.youtube.com/watch?v=6mvGke8UgR4
 
When I first was dumping the oil I didn't realize there was an oil plug on the bottom so I tilted it on it's left side, almost upside down, to get everything out from what was sitting in there for its years of no use.
 
I have let it run for a while and nothing is changing. The oil in the reservoir isn't going down so it doesn't seem to be burning up what's still in there. I cleaned up the mess you see in the video after my first run, I think that was all the carb cleaner shooting out, since then only gas is coming out, no liquid.
 
I could cut my lawn using a gas mask, but I would prefer to try to just stop the smoke instead.
2020/10/16 09:49:30
kshansen
A couple thoughts.
First and worse for the engine, maybe the rings, piston and or cylinder are in bad shape and it may never run right.
 
Next as you admit you did not know how to drain the oil do you know how much is the correct amount of oil to put in the engine? If over full it will tend to burn oil.
 
As you had the engine flipped over to drain oil you may have got oil to places it should not be and now it just needs to clean itself out.
 
You may have just found out why this engine was tossed in the pile of junk you found it in. Also the lack of oil in it when you drained it is another sign it is not in good condition.
 
My only suggestion would be if you are sure the oil level is correct wait for a windy day and put it to work mowing the lawn and see if it des clear up after it works a bit. At least you should not have to worry about mosquitoes for a few days!
 
 
2020/10/22 06:45:56

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