B&S Intek V-twin Valve questions

[Arkie]

AND keep a heads up and do not forget to re-install the breather tube into the rear of the air box.
If you forget this the carb WILL suck unfiltered dust dirt straight into the carb throat on that model engine and the rings will go fast. I've seen quite a few of them that Bubba overlooked such.

Also as Ke4 mentioned set the valves are a snug .004 and it's quite common for the .004 to become loose after few hours of operation and require a re-adjustment. Usually the second time adjust will hold.

Also just adjusting the valve lash normally will not stop oil smoking.
Take a look/smell at the oil level and also make sure it's not gas contaminated.
Might even think about changing the oil to straight 30w and do not overfill.

I've seen some of them type engines that a head gasket would start seeping/leaking and at first would produce intermittent smoke and then progressively get worse.

Also hang onto your OEM Nikki carb. The clone carb replacements are iffy.
There is some good on-line info about how to re-build those Nikki dual throat carbs and as Ke4 mentioned/hinted the o rings on everything inside the bowl needs replaced usually.

[rootuser]

It seemed to be the valves on the smoke issue because I think the valve seals are iffy and with the valves with no gap it would be sucking oil passed those seals even faster. Now that they are adjusted no more smoke under any speed or load. I am sure they will go completely and then will be making a total mess all the time. I've seen this before in motorcycles as the first sign the seals are going. I'll drive it until it drops. The mower has seen better days overall being 26 years old so it might be time for a new one so I am hoping I can get this season out of it.

The oil is fine, checked for contamination and it was dead at the full level. I'm pretty careful. Hasn't been burning any oil until recently and now that seems better. Can't tell until whatever cause it (Rings, valve stem seals, whatever) goes out completely and doesn't seem to be intermittent.

I have a rebuild kit for the carb and I have a ton of super tiny o-rings from building micro electronic components for years so hopefully I have all the right stuff, although the jets just falling out worries the crap out of me lol. I've never had a carb like this before so it will be a new experience.

[Arkie]

Jets just falling out are no real concern unless they fall out un noticed onto the floor. They just seem to be gone and evaporate. Same with the new itty bitty o rings if in the kit. they go somewhere and hide.
The little o rings around the press in jets has to be a snug proper size for a good seal around the jets. Some kits have the jet Orings and some kits do not.
I buy the itty bitty O rings in bulk. They can get pricy if purchased each.
Pay attention to the instructions for installing the itty bitty o rings onto the jets and then pressing the jets back into the plastic emulsion tube.


Here is a link to some info on repairing your carb.
When searching for Nikki parts #'s use Briggs instead of Nikki before the parts number.

here is some info I had gathered and saved on file for reference that helps before going into the dual throat Nikki's.


Pg 1 of 2
5 2017
Small engines repairs links
Carbs, etc
https://outdoorpowerinfo.com/repairs/

12/2022
Nikki dual throat carb repair/rebuilding links
Nikki dual throat carb tips and re-building LINK.
Guy asks about jets sizing and re-building a dual throat Nikki carb
https://www.lawnmowerforum.com/threads/ ... ets.29187/

You tube video part 1: (newer style aluminum float bowl Nikki) USE KIT 54832 @ $7
https://www.youtube.com/watch?v=uPWul3T0fRE&t=429s

part 2 (older model with steel float bowl) USE KIT 54833 or 54834 @ $9 each depending on the style of Nikki. See part 2 of the video to determine which kit needed.
https://www.youtube.com/watch?v=Jvnu_eEGXRM


A kit that has the o rings/gaskets
Amazon.com: 797890 Carburetor Overhaul Kit for Brigg 791230 799230 699709 499804 MIA10632 Carb V-Twin 4 Cycle 20HP 21HP 23HP 24HP 25HP Engine John JD MIA10632 LA135 LA120 LA130 LA140 LA145 : Patio, Lawn & Garden

Use these numbers when browsing for a kit.
APHP 797890 796997 791230 Carburetor Overhaul Rebuild Kit for J&D LA120 LA130 LA135 LA140 LA145 LA150 LA165 LA155 Z425 Z245 L111 L118 L120 X140 D150 D160 D170 Lawn Tractor Husqvarna YTH22V46 YTH2348