I have a B & S 10A902-2072 lawn mower, that's had a hard life in outback Australia. It's still running (just) but I've just had it apart to clean out the carb, and I'm having trouble sorting out the linkages - yes I know, digital cameras are for when you pull things apart, but ...

There's the governor blade that catches air from the flywheel, and there's also the throttle on the carb itself that needs controlling.

Does anyone have a diagram or photo of the carb and linkages?

I've checked out the parts list and owners manual from briggsandstratton.com, but not enough info.

TIA, Peter

4.5 hp? the windvane governor, theres one linkage from that,( looks like a " V " on the carb, thats what it connects to to open the butterfly in the carb, newer ones take two springs instead of one, both to the loop in the one link, then the hole on the speed control lever on front. going on this from memory, but that loop i beleive should be closest to the throttle control. this engine is a windvane (the plastic blade there) governed engine, rather simple, has no internal governor, but the windvane can get some rust on that long screw (holds the coil on as well) stick it, or dirt can. good to make sure its cleaned......


have you just cleaned the carb? or went ahead and got a new diapragm? i'd go ahead and get a new diapragm, they are pretty cheap and can get hard and cause em to run bad. also the pickup tubes, make sure the mesh screen is clean and clear.

hi bugman, thanks for such a quick response.

http://www.hobbytalk.com/bbs1/attachment.php?attachmentid=24518&stc=1

See the attached image (hopefully it's come up). The main throttle cable comes in from the top right, the governor windvane on the top left. The butterfly control lever you can see in between those two. As you can see, I've only got one spring, from the throttle pivot to the governor - the butterfly valve misses out :cry:

the governor blade moves freely, that doesn't seem to be a problem. I soaked the whole carb in petrol (gas in US of A language) and got to the mesh screens with a toothbrush so they should be ok. I haven't got a replacement diaphragm, just thought I'd try it first to see how it goes, maybe go that step if necessary.

thanks again, Peter

looks to me like its missing the linkage from the governor to the throttle shaft it hooks in @ the governor arm closest to the flywheel then in the butterfly throttle shaft then from there to the big control with the spring

same here, your missing the linkage to the carb, from the windvane. as for the carb, carb cleaners better, but gas should do somewhat of a help. you have the main spring from the throttle control to the windvane, the spring should be from the link to the throttle control, link from windvane to the throttle shaft (its the " V " shaped part on the carb) carb does still look a little dirty in there though..... if you can find a can of carb cleaner, use the straw that comes with it and go over it some more, it'll eat the stuff right off. wear automotive gloves, carb cleaner will dry your hands out bad. any parts for this carb can be gotten at a small engine shop around you, they may even have a couple used ones for parts....

thanks guys. I think I've got it sorted. I'd like to be able to freshen the carb up a bit, but where I live in outback Australia is over 400 miles to the nearest small engine shop - no kidding.

I got a good picture of b&s linkages, if anyone wants it for future reference. See:

http://www.lawnserviceforum.com/showthread.php?p=118377#post118377

or:

http://home.gate.net/~kd/briggslink.jpg

thanks again, Peter

ah yes, also went to check one to be sure on the linkage, the loop in the link is away from the throttle control.

I know this is a very old post But does anyone have a picture of this carb with all the springs attached? Also I do not have throttle cable on my mower(just picked this up for a project) Don't even see where one was ever attached to the handle. Call me stupid or what. Does this engine use a throttle or is it automatic???

Some engines have the throttle set to operate at a specific speed, and are not adjustable. I don't have any pictures of this set up, but if I find some, I will post them.