Fixing Briggs and Stratton 6 HP Quantum lawnmower engine

Joined
Dec 31, 2017
Messages
17,975
Location
SE British Columbia, Canada
I recently solved the no-start issue on a 6 HP B&S mower engine. It’s 20 years old and was the series when they used a red bulb to prime the engine rather than have a real choke assembly. This engine is overly susceptible to a no-start condition due to old gas and the carb can get clogged up easily.

The red bulb actually pumps air to cause a venturi effect to bring gas from the bowl into the carb and uses a large plastic plate assembly to house the bulb and priming circuit.

You tube videos suggest doubling up the gaskets between the carb and plate, and removing the bulb assembly and cleaning it up. Those things did not work here. I also removed the bowl and sprayed the carb with carb cleaner with no improvement.

The easy way out was to order a carb kit made in China that came with a new carb, plate, fuel hose, shut-off valve, gas filter, air filter, governor springs, spark plug, blow by hose, clamps, heavy duty air filter cover all for $30 US. It runs fine now, and has the shut off valve and fly screen filter installed. Incidentally, this is for the widow of the LEO who has a place down the street. Here are a few shots. Enjoy.

C4557774-CCFB-4D11-BF91-6212A951399F.webp


5F476082-7A7A-438A-8390-6D17786B6B25.webp






17BE6688-AA03-44DC-A727-6C5A86A731D8.webp


06704613-9E58-4E54-B497-BC533B679BB7.webp


420AE9F3-1412-4541-AAA2-2E3A88DB3762.webp
 
Last edited:
It is sad that it is just easier to replace than repair.

I had the same answer from local shop on maybe a snow blower or thatcher. I inquired about a rebuild kit and looked on online. Parts kit was like $50 with shipping, Shop said the same plus labor and that they pretty much just get new for less cost. Same deal about $30, came with everything including new lines, a couple bolts and ran great.

Nice job and good karma for you helping out.
 
You're a real gem to put a fuel filter on this. Bugs me these never came with one to begin with. That baffle on the new one really helps to line up the gasket it appears. I honestly didn't know how long these Brute's have been made. I convinced my Dad to buy a self propelled push mower & these were being sold at our local WM that is a 6.25 HP. He put many hours on this & then gave it to my brother which knows how to ruin everything. Not pictured is a 2014 6.75 HP Brute I bought from Menards brand new & gave it to my son for his property a few years back. Plan on restoring this one below the best I can afford to eventually. ha! Again, I didn't know these were made 20 years ago. cool & good job!

IMG_20210714_164537.webp
 
I had the same problem with a barely used 25 year old mower my dad bought. A new carb made it run like a champ but it still required a spritz of ether to get started. I sprung for a complete new primer bulb plate for $20 and that fixed it even though I couldn't see any problem with the old one.
 
Back
Top Bottom