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Mobel 12h802 type 1922-B1 code 00031756

Have rebuilt carb by diassembling, soaking and installing new rebuild kit. Mower continues to only run a few seconds and dies. It is a primer type carb, while running, I can get to stay rough running while continue to pump primer. New gas, new plug, new fuel line and new air filter. Have tried running with and without air filter, no change. Any hints or suggestions????

Hi Princeal

Welcome aboard to LMF hope you enjoy this place,what part of Iowa are you from i'm in the southwestern mn? I'm not sure what happen to your carb i was think maybe if you could take off the bowl and see if the needle and seat look ok and have you tried different setting to see if that helps? And see if your float bowl is on the right side being the low side for the float to fall into? Only thinks to look at good luck:tongue:

Noma thanks for tips I will try them. I am in the far southeast part of the corn state living on the mighty mississippi with Ill. and Mo. on the boarders. Thanks again

update tried readjusting float made sure it set level. blew into fuel inlet when turned upside down had air turn right side up no air which I believe to be correct rechecked plug gap as well. and coil gap. No change I can keep it running if I play with linkage as soon as stop mower will die. Any help is greatly appreciated

If you can keep it running by "playing with the linkage" then you likely need to turn the idle speed screw in a little.

Jeff
No adjustments I take it is controled all by the govenor . I am againist buying a new carb more for the reason I know I can figure it out and I just hate the whole idea of replacing parts not repairing. But it just might come to that. Thanks for the suggestion though.

Make sure the jet in the bowl nut is clean.

ILENGINE
Thanks for the tip. Rechecked jet all clear. I decided to adjust govenor and did so mower started and ran but idled too high at lowest speed setting so I shut it off adjusted back to original setting and now back to original problem run a few seconds and die.

The guvnor during might need to be replaced

When the governor starts going back and forth , engine idle goes up and down as the engine fights to get air - check your carb to block gasket . Another old issue with over working governor is valves out off adjustment .
Take valve cover gasket off and rotate the engine by hand until the piston(s) are at top dead center . Get your feeler gauge out and see how much gap is between the valve & lobe - if needed tighten the assembly back down .
Rotate by hand again until the piston is at bottom dead center. Check the exhaust valve clearance .
The carb settings should be at stock setting - 2or3 turns out after seating them gently .
You can't tune the slow idle fast idle air fuel mix until you get rid of the carb fighting to get air .

Have tried everything I can think of to get it up and running NO LUCK.cheked carb to engine gasket brand new have recleaned and reassembled numerous times still nothing. there are no adjustments to be made (idle screw etc.) unfamiliar with valve settings I guess I did not know they were adjustable . Anyone have any more suggestions I hate to give up but getting close.
Thanks
KJR

I have a simplicity and Jacobsen that work 10 hours a week cutting 23+ acre - at a time. There is a tightening bolt on the small valve assembly can back off a feeler gauge in size . It is under the square valve cover .
My machines are all 1982-1986 simplicities and one Jacobsen . When the Jacobsen starts lopping when running it is tune up time - every three weeks or so due to it's age and hard work.

you have a fuel starvation problem.....you missed something in the rebuild.....is your idle screw turned out far enough?....are you sure theyre arnt any adjustments?......you have a primer bulb...is that correct?.......i guess you checked the float needle.....you may not have cleaned it all the way....retrace your steps......pictures or video help :smile:.............. http://www.partstree.com/parts/?lc=briggs_and_stratton&mn=12H802-1922-B1&dn=09900003 .....dont mess with the governor linkage........how did the engine run prior to rebuild?

Reddragon
Thanks for the reply and I have to agree. I have now disassembled one more time and it is currently in a soak. It has no adjustment screws and I have replaced the needle and seat and checked float adjustment . I am hoping that a longer soak will dislodge whatever it is that is causing the problem and I will be done. Again thanks for the advice

compressed air will help a great deal too :smile:

So far this has been a great learning experince,but I am a little leary to tackle the carb problem on my other project mower that has a tecumseh. I rebuilt that carb and all was all right until the kd that it belonged to ran it out of gas and now all it does is leak gas out the screw on the side. But that another problem for another day after this Briggs as been tackled:confused2:

well.....whatever your problem.....were here to help :smile:

Ok I am crying uncle. After a nice long soak and volumes of compressed air same problem exist. Runs for a few seconds dies,keep priming will run. I have checked with and without fuel cap,have unrestricted gas flow from tank to carb. etc.etc.etc. still no run Any suggestions?

ok..theres an internal blockage in the carb....the emulsion tube may be adjustable and isnt in the right position....also..the needle may be the wrong size...give us any info cast into the carb..like numbers and name [ like nikki or walbro] i have carb rebuild manuals...can you take pictures of the carb?

princeal said:

update tried readjusting float made sure it set level. blew into fuel inlet when turned upside down had air turn right side up no air which I believe to be correct rechecked plug gap as well. and coil gap. No change I can keep it running if I play with linkage as soon as stop mower will die. Any help is greatly appreciated

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what you said here worries me...it sounds backwards.....when you say right side up....do you mean the way the carb sits on the engine?......almost sounds like your float is upside down

Have you checked the condition of the air cleaner gasket? If the gasket doesn't seal properly you won't get any fuel draw at all. I've fixed too many mowers to count just by replacing this simple gasket. It's part # 163 on the parts list for your engine. Good luck

Does your needle have a metal tip or a rubber tip?


Rob

IFIXDIT
Thanks for reply gasket is brand new thought
Taxidemist thanks to you to- needle has metal tip it and the seat are also brand new new.
Reddraggon- I will taking pictures of carb shortly and posting with carb numbers. as far as the confusion if i hold the carb bowl up and blow through inlet I have air if I turn right side up(As would be om mower and blow no air is this right?:confused2:

princeal said:

...if i hold the carb bowl up and blow through inlet I have air if I turn right side up(As would be om mower and blow no air is this right?:confused2:

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That sounds backwards...with the bowl empty and held right side up, (as it is when mounted), the float is down and air should flow through the needle & seat... :smile:KennyV

no...thats backwards...if the carb is upside down...the needle should seat itself ...................and if right side up..[like on the engine].the float should drop and let fuel [air]in....[ if the bowl is off]

Kenny and i saying the same thing! :biggrin:..........the only way it could be opposite is if the needle was on the other side of the fulcrum

You are both right I have had the thing off an on and right side up right side down so many times I have forgot which is which. The numbers on the carb are B126 with the b possibly an 8 and the 6 possibly being a G on the other side of the mounting flange is 0700 with the last 0 possibly being a D they are all ran together so made I cant tell. Hopefuuly the picture will load and be of use.P.S. The carb rebuild kit I was sold is Briggs #498260

if you have a old guitar string handy, use a short piece th probe all the holes in the carb, guitar string is soft and wont hurt the carb, and sometimes you can take a plastic or wooden handled screw driver and rap or hit the carb on the outside of the body, lots of small blows can dislodge stubborn blockages, hold it over a white paper towel and see what if any thing comes out, be careful not to hit ant moving parts or gasket mating surfaces, good luck

ok...ill look some stuff up...but just from the pictures...that carb has alot of corrosive damage..doesnt mean it wont work... but doesnt mean it will either [depending how much damage on the inside passages]

well...it looks like you have an old style version of the carb [without idle screw]...make sure that needle seat you put in was the right way.....it worries me that the governor linkage was messed with....do you think you can get it back to factory shape?....and all the linkages hooked to the carb properly?....its easy to get them wrong and will cause alot trouble....could you take some pictures of the engine where the carb goes on and the linkages?.....is the gas new?

i see the earlier thread of new gas.....how bout that primer bulb....is it new?...and is it seated all the way down tight?

I reset govenor to where it was.There is only one linkage to hook up. The primer bulb is not new and have debated replacement. Have gotten kind of side tracked with a broken toilet and smoked ceiling fan all in 2 days. I may purchase a new bulb tomorrow. Carb is corroded but when i pulled the welch plug that passage did not look bad. Carb also took on a dark color once it was soaked for a couple days. Needle seat was seated with ridges down. Thanks again for the help

ok.....i think your damn close to figuring it out.....be sure to plug the welch hole back up [thats where an idle screw would have gone].....and make sure the gaskets on both sides of the carb are good......oh one other thing...when you were blowing the seat area out....make sure it didnt come out of its position :thumbsup:...i would use some starting fluid on your next try.,.......keep us updated:smile:.........that primer bulb /air cleaner base may be whats hanging you up......http://www.partstree.com/parts/?lc=briggs_and_stratton&mn=12H802-1922-B1&dn=09900004

princeal said:

I reset govenor to where it was.There is only one linkage to hook up. The primer bulb is not new and have debated replacement. Have gotten kind of side tracked with a broken toilet and smoked ceiling fan all in 2 days. I may purchase a new bulb tomorrow. Carb is corroded but when i pulled the welch plug that passage did not look bad. Carb also took on a dark color once it was soaked for a couple days. Needle seat was seated with ridges down. Thanks again for the help

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when you say ridges down.....they need to be toward the carb and away from needle..is that what you meant?

Yes ridges down away from needle I have purchased a new primer bulb yet to install.hopefully this will be the key. Thanks again

thers alot of problems in the primer bulb area...sometimes those little foam filters behind them disintegrate and plug up stuff

princeal, I have the same exact issue on my mower, looks to be the same identical carb, just not quite as much corrosion.

B&S 123K02-0336-E1

Illustrated Parts Lists | Repair Parts & Maintenance Products | Shop | Briggs & Stratton

Have taken the carb apart and cleaned it about 4 times, haven't soaked it though. The needle/seat are new, carb/air filter gasket are new. Have checked the bowl nut and main jet both visually and with small wire, no blockage. I can also blow air from the fuel inlet and it moves thru normally in the upright position, and no air if upside down (so the float is working)

I can keep the mower running indefinately while pumping the primer bulb.

With the air filter off and mower running and pumping the primer bulb I can see fuel shooting up the main jet into the carb. Once I stop pumping the bulb the fuel stops shooting in and mower stalls.

What is the theory behind the gravity feed? I have fuel in the bowl, where does the suction/vacuum come from to pull the fuel up the main jet to mix with the air? Is it just suction from the air moving past the main jet? Or is it pushed out by pressure in the bowl?

I don't mean to hijack this thread, but will be watching closely for the resolution.

Thanks!

fuel is drawn in from the suction of the piston going down....the gravity just fills the bowl

Most recent update NO CHANGE. Replaced primer bulb used starting fulid same result 4-5 sec run time and dies I refuse to give up but I can not figure out what my next step should be. As before I checked govenor etc. everything seems fine. Should I try to readjust the govenor ?

Ok, now I'm really scratching my head, but it is running.

I've been suffering trying to get this running for nearly a month and no clue what the cause was. I had it apart for the 5th time today hoping something would jump out at me as the cause, but after walking away from it for a few hours and coming back to put it together, clean up and call it a day I gave it one last shot.

Fired right up and kept running. The only thing I can think is perhaps there was a seal that wasn't completely tight. But I changed nothing from all the other times it was taken apart and inspected/cleaned.

Maybe it was just the luck of posting on this forum that did it...

I wish I had more to help you with, princeal. Sorry and Good luck!

no...dont play with the governor....i think you should get a good used carb....theres alot of corrosion on that...and its something deep inside....you gave it good go:frown:

ok here is a new twist to things. I had a another carb setting around that was basically the same( no adjustments,idle screws etc.) I put it on and have the same outcome 4-5 sec run time and then dies.If a play with the govenor linkage I can keep it running so I now am stronly leaning towards govenor adjustments. What do you guys think?

you can disconnect the governor linkage from the carb and hand control it...tell us if you can keep it running

hand control carb or hand control governer?

the carb....dont mess with the governor...in fact... disconnect the linkage...if you put resistance on it..you can break it

I had some luck playing with the choke on the carb, I could keep it running a few seconds longer than doing nothing. But I has the most success pumping the primer like it was starving for gas. The only thing I kept thinking its it was plugged...

Reddragon
I can keep the mower running by playing with the carb. I had the govenor linkage disconnected. I reconnected the linkage and tried and came back to the same problem 4-5 sec run time.

something is cutting out your fuel....either clean more completely or get another carb core:frown:

Hi
Still sounds like a dirty carb to me take it back off and take it to your local dealer and ask them to put it in their sonic cleaner, this will shift any dirt that has built up inside the drillings and bits of the carb that you cannot clean with an air line.

Is the governor trying to open the throttle? OR is it trying to Close it?... It is possible to hook it up back wards... :smile:KennyV

To all the followers of this post I am calling it closed on my end. Have been trying many things none have worked. Kenny V.'s suggestion was my last hope but no go. Mower continues to run for only 4-5 seconds then quits.The owner who I was trying to do a favor for does not want to spring for a new carb (38.00) or an ultrasonic clean at the local mower shop (20.00) so I am washing my hands of it and giving it back.Thanks again for all your help.
KJR:thumbsup::thumbsup:

Hey piecemeal Are you ready for the cure? It happened to me! you know that nut/plug that holds the bowl on to the carburetor. Look at it close, it has holes in it and they are plugged! It drove me up the wall. I must have had that D@#$# carb off 7 or 8 times before I finally figured it out. so don't feel bad at all.

Princeal: Sorry I misprinted your name. and that I was so late in replying. I am a new member just 2 days, so I only saw the thread today. It's just the irony of the problem. that part is one of the first to come off, and since it is obviously just a fastener it is set to the side, because plugs don't need cleaning, I still feel stupid over it, But it is easier to laugh when you know you are not alone.http://www.lawnmowerforum.com/images/smilies/laughing.gif

Thanks for the reply but I have already tried that and the holes are clean,don't worry about the name mistake. I hope you enjoy this forum as much I have .:smile:

i understand how you feel ....ive had 3 carbs recently put a hell of a fight...one had a muddawber nest in it [ in case you dont know..they're wasps that make better homes than the Anasazi indians]....the only way to clean it out was to remove the plugs and drill the passages back out [fun!]....another was a spider had died in a bleed hole [the same cure]....the other was hopeless....[corrosion]...sometimes its just time to get another carb

princeal,

Please go to the following web site, find your carb and follow their instructions. I had the same problem last week and it was the small hole above the threads ( in the nut and jet that holds the reservoir cover in place). The hole is so small you won't know it's there unless you follow their instructions and pictures. It is an idle port and if the hole is plugged the motor will not start. There are two larger holes that are very easy to see.

Small Engine Equipment Troubleshooting, Repairs and Safety

I discovered the web site in the FAQ program and it solved my problem in just minutes.

Tricky

Trickidicki is right sorry I was not more detailed. the large holes in the base of the plug let the gas get to the itty bitty hole in the top of the plug so the gas can get to the metering port at the top end of the tube in the center of the carb. the small hole offset from the center of the metering port is the inlet from the Prime bulb, which is why it will run as long as you keep pressing prime bulb. so even though you have plenty of gas in the bowl it can't get to the metering port, but the prime bulb takes slightly different route. but still ties into the metering port, or whatever they call it now that the took away the mixture needle. you can see both ports in the pictures that princeal attached, and judging from the corrosion I am fairly sure that we are right about why it only runs when you prime it.. I would advise you not to enlarge either hole too much. Because it may make the engine run too rich, or too fast. good luck

Did you take walsh plug out on idle port side of carb. There are small holes in they for idle and throttle up . Check the emulson tube in carb. When running hold throttle at idle if it dies it is in the idle side of carb

seems to be a blocked passage, get a brand name carb/throttle intake automotive spray type cleaner / remove any idle - etc adjing jets & spray into each along with into fuel tank / i have had some issues also - may take many sprays - you got the reg specs set - don't use cheap stuff - amsoil power foam injector - I don't sell it but a friend supplies & has worked for me- use it or a good brand name - like jd at lowes is not a jd!!!!!!!!
steve

STEVES said:

use it or a good brand name - like jd at lowes is not a jd!!!!!!!!
steve

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I agree it likely needs cleaning...

BUT a name brand IS a name brand.... I have a scratch pad that says JD on it... I know JD didn't make it and I can not hitch a 40 foot disk to the note pad... BUT it is JD ...
Lowes didn't put the JD name & logo on the lawn mowers... JD did,... so it IS a JD, and it is JD that May suffer a black eye over quality not Lowes... :smile:KennyV