Monday, March 10, 2014

Briggs And Stratton 8hp Snowblower



Hi all, serial number is 190412 0921-01 77092110. This is and old machine and it was running(i just bought it used) but it never started without me pouring a bit of gas in the sparkplug hole. Now when i put gas in the hole it will burn that gas but die right after.Ive checked the fuel lines and filter and pulled the carb off but i know very little about carbs.The bowl where the float sits in had rust and was bone dry.Is this normal? Im getting spark so does this seem like a carb problem and if so how hard is it to put a kit in?Thanks for any help.

Hello long been a long while;
how you doin'?
First make sure that the fuel on/off valve under the fuel tank is on (if yours has one).Then take fuel line off at carb.to check fuel flow. check fuel filter too.
If it's flowing good,then yeah,it's a clogged carb.And no a kit isn't hard to put in.Less you bugger the brass main needle under the high speed jet.A kit has 3 differant bowl gaskets so make sure you get the right one put on.
That's it adjust each screw to 1-1/2 out from just barely snug,fine tune adjustment from there.

Thanks for reply,ill try and locate a carb kit and see how it goes.

and before you go to get a kit, make sure to get some carb cleaner, and soak it good for a couple hours maybe, then make sure to blow it all out with cleaner and compressed air if you have it, i'd also get a needle and seat kit as well. be sure to soak all the carb parts with the carb, the carb has to come totally apart to make sure it all gets cleaner on it. they are pretty simple to put together.

Hi, thanks for the reply. I took the tank off and there was a blockage so i cleaned it all up.I took off the carb and pulled it apart and the inlet needle popped off. Does that needle just hang from the piece of metal under the float? im going to get a kit and see how that goes.ill keep ya posted.Thanks again!

Yep, the needle has a clip that lets it hold loosely to the float tab (if you have the older carb with a metal float). If it's a plastic float, the needle just slips in a notch on the float.

Ok great, im picking up a carb kit and will be putting it in this weekend.It is the older type metal float and i see now how it fits.Thanks for reply and ill post how the kit goes.

Well now ive went and done it. I was all set with the carb kit and i went to unscrew the brass tube and snapped it and messed up the threads on the bowl to the extent that i need a new one....ive been searching with no luck for the bottom half of the carb at small engine shops. I live in Sudbury Ontario Canada and im wondering if anyone knows where i can get a used or new bottom half of the carb. I will pay for shipping etc if i need to just not sure where to locate one.the serial nummber is 190412 0921-01 77092110. Its an older model so thats maybe why im having diffuculty finding one.Any help would be much appreciated.

Briggs does have a special tap set that will clean up the threads, it is part number 19245. Otherwise, the carburetor lower body is part number 391909.

ive located the part i need from a small engine shop.Thanks for reply, ill attempt the kit this weekend and post how it goes.

I got the carb part and put the kit in and i cant get it to start. When i first got this machine i had to pour gas into the sparkplug hole to get it going then it ran ok. I decided the carb needed a kit and put that in but now i cant get it to start at all even by pouring a bit of gas in sparkplug hole. This is what i did, replaced set screws and slacked them off 1 1/2 turns each to start, replaced brass feeder tube in bowl( i tightened this brass feeder very snug, is that the right way and there is no gasket for that tube right?) i replaced the inlet needle and wire that it hangs from and the small washer/gasket that the needle seats on, i put it in groove down and adjusted the float so that its parallel when upside down to bowl. i pulled plug and checked for spark which i have...if i pour fuel in the sparkplug hole and there is spark then it should run even for a few secs right?im baffled and frustrated but wont give up, anyone have any ideas id be glad to try...i also pulled off the gas tank and cleaned all parts and replaced the gas line so the fuel is running great when i take fuel line off the carb it pours through no problem...thanks for any replies!! here are pics of my carb http://roblirette.piczo.com

one thing that can happen, is that the plug is getting gas fouled, and won't start there after unless its dried. you can try gas down the carb instead of the spark plug hole deal. i see in your pictures the brass feeder is hitting? hitting the butterfly?

Thanks for reply. The pic is not of the best quality but the butterfly moves freely without hitting the brass feeder, im just wondering if that is the way its suppose to fit, like screwed in all the way till snug. I bought a new plug today as i figured the same, that the plug may have been damaged or fouled and still nothing but i dont see how i can pour gas down the carb seeing its a closed top unless i pour gas in the carb then bolt the other piece on and then attach it to engine.. are the 2 screws i indicated in pic suppose to be 1 1/2 turns out after snug? http://roblirette.piczo.com

hat carb is termed an 'updraft' which sometimes makes it difficult to pull gas up that high during starting. If it won't fire by putting gas in the cylinder via plug hole, you must have either flooded it or there is another culprit. Make sure you have spark. If the plug is wet you probably won't see a spark.

ill try it tomorrow with the new spark plug and see what happens. thanks for reply.

still trying to get this thing running, way to cold to work on it outside so im going to bring it in the house and keep trying things, still puzzled as to why gas down the sparkplug hole wont work, even with new plug??? ill keep tying but please throw any ideas this way if you have any..

You never did say if you were getting spark after all the things you've gone through. I suspect this is an old machine with points under the flywheel. Even frost can stop the points from working. I would check for spark and if none I would then go to the points. If you're getting spark go to fuel. If it wont fire youre either rich ot too lean. Is the plug wet? Are you using GOOD gas. Old gas sometimes won't fire at all when cold. Squirt som new gas in the carb with a squeeze bottle of some type (nipple on it) Make sure that little quarter inch bolt is in the bottom or the gas will just run on the ground. Then close the choke and pull on the rope a few times -- it should fire. If it does and won't keep running it's not getting gas. If it doesn't start after trying this several times the plug should be wet. If not--gas is not getting to the cylinder. Trouble shooting without any equipment is easy for me because of years of experience but it's sometimes hard to help others without showing.

Don't replace the points--just clean them and gap them at.020 in the open position.

I am working through holidays but will be bringing the machine indoors this week and i will start from scratch and try everything that was recommended and get back to you, thanks for reply.

this maybe a stupid question but when i hold the sparkplug while its attached to the sparkplug wire near a bolt on the engine i see spark but there seems to be no spark between the gap of the plug only from the end of the plug to the bolt on the engine...it must be firing cause it seems to want to run but just wont go..its a hat carb so air forces the fuel up and i cant pour gas in the carb and gas in the sparkplug hole doesnt get it going..i heard a slight backfire a couple times also...

hold the plug to the shroud or head, should give a strong spark, gets a weak one, the spark could be getting blown out.

Did you ever check the points? This is an old macine, manufactured in 1977. Briggs switch to solid state in 1981 (pointless)
I have a 190707-1148 (similar to yours) on a riding tractor and while I was driving it stalled. I regapped the points (somehow they weren't gapped properly) and sanded them and the engine ran like new.
Try that.

Sounds to me like you have a bad plug if it's sparking from the plug to the engine, rather than across the electrode.

The plug is brand new and i dont see points, there is a magneto coil...im inclined to think this is a fuel issue and im wondering if the brass tube that screws in from the bottom of the carb on an angle is suppose to be screwed in tight? i just screwed it right in tight and left it like that but is there a setting for that brass tube? there is an adjustment screw that screws in right behind it on the bottom of carb, i screwed that one in and backed it out 1 1/2 turns and the adjustment screw on the top was set the same..are these the proper settings? When i took the top intake(the carb intake bolts directly to the engine) off the bowl was full of gas and the float seems to be set right as its not flooding but my plug is dry when i pulled it out,also when i crank it over there is a suction from the choke intake so its getting air???

77, should have points, they are under the flywheel, flywheel has to come off, unless a conversion kit was put on it. that brass tube should be in tight, though don't force it hard in, the baseline on the screw settings are 1.5 turns out from all the way in snug. you could try a quarter turn more on em, seeing if it affects anything. are the needles original or new? not damaged?

Yep. a '77 would have originally had points. A bad condenser could cause weak spark. I'd forget about the points, leave them in there, and buy a replacement coil (new coils come with solid state ignition built in) and install it. You won't have to worry with breaker points again.

ok, yes the needle is new, i bought a carb kit and this is where my problems started..how does this type of carb work? like i mentioned its a hat carb so i understand that air is drawn in but is the gas sucked from the bowl into the intake? What purpose does this brass tube serve? Is there air running through this tube or gas? Ill look into a new coil but there is spark when i hold plug near a bolt on top of engine and pull cord. Thats why i say it may be a fuel issue but if i knew exactly how this carb operates i could eliminate certain things and pinpoint the problem. Thanks for the time and effort on helping me with this issue.

sucks gas through the tube, in this case, its hard to do so..... you may seem to be getting good spark though when you check it, even though you aren't and the sparks so weak, its getting blown out.

I pulled the magneto and cleaned everything up. I took the carb apart again and checked everything and put it all back together and it really seems to want to go, its so close to running but just wont go..im going to replace the electric starter so i can adjust while im turning it over.

I've done everything mentioned in these posts and still can't get this machine(8hp briggs w/same carb) all new. I can only get spark when disconnecting the ground wire from the condenser where it attaches below the carb to the linkage bracket. Off key also hooks up there. And seems like it's not getting enuf mix in the cylinder. If I close the choke all the way it will fire but not run. Even sprayed starting fluid on both sides of crank while turning over to check for bad seals w,no effect. All gaps are set to specs.

found that the flywheel pin was sheared again. cheap one that came with the kit. picked up some genuine BS pins and now it will start,but only run on 3/4 to full choke no matter how I adjust the jets. Sucking air? ordered new head gasket,intake gasket and elbow gasket. took gasket out from between upper lower carb then checked with feeler gauge w/o gasket and found one spot by the port that i believe goes to the cylinder I can put a .008 feeler between with a little room. could that be where it's getting air? take all the help I can get. Thanx All.

I doubt it's getting air, but it's possible. You much more likely have a carburetor that needs cleaning.






Tags: briggs, sparkplug hole, brass tube, brass feeder, bolt engine, does this, getting spark, make sure, spark plug, Thanks reply