BR 400 blower leaking gas like a sieve

slomo

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Carb issue flooding the engine.

How did you "check" the fuel hoses? A visual or under pressure?

slomo
 

slomo

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Was this out on the -29F weather a few weeks ago?

slomo
 

wolfey01

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The carb on a 2 stroke engine has two "flapper " valves that serve as fuel pump and feed for the engine. After a few years these valves can get brittle to a point that they don't seal the gas anymore. You have two options. (1) rebuild the carburetor. or (2) Replace the carb. The fact that the engine got "hydro locked" is a fairly good indication that the flapper valves ( my term) are bad and no longer sealing. Alcohol based fuel is very hard on fuel lines and carburetors.
 

trooper1954

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Slomo....just a visual check, and no, unit stored inside an insulated shop.
wolfey...would it be a major job to rebuild the carb? I'm game, but have never done that before....some say cheaper and quicker to just put on a new carb but interested in what you think? Downside of a new carb is it will be from China most likely, and I'm with the rest on their quality control! :)
Is the "flapper valve" what I call the diapghram....the rubber seal that pushes up and down in the centre of the carb when you take the cover plate off?
 

wolfey01

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The diaphragm is what I was talking about. There are two flapper valves that seal on one side when the other is open and vice versa. They aren't difficult to rebuild as long as you watch the order of disassembly closely. ( take pictures) The rebuild kit will probably fix the problem, and you are correct in assuming that a new carb will be made in China unless you pick one up from the dealer. I would be very tempted to buy the rebuild kit from a dealer also so you are guaranteed the correct one.
 

trooper1954

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wolfey01....is this what I need?Screenshot_2021-03-11 Carburetor Repair Kits for 4203 SR360 BR320 BR400 BR420 Blower Amazon ca...png
 

Fish

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So guys.....here's the update.
Took the thing apart today and checked the fuel hose....nothing found.
tried to start it afterwards and gas spewing everywhere again.
Took the plug out and pulled the starter.....gas spewing out of the cylinder head plug hole!
Cylinder head and crank full of gas....hydrolocked.
Took the carb apart, cleaned it a little and re assembled....nothing found.
Tried to start again.....spark evident.....will not start but fuel spewing has stopped....no leaks.
Put small amount of gas in cylinder through plug hole...still won't start.
After attempting to start for 1/2 hour have given up.

Surely, with a spark and a small amount of fuel in the cylinder the thing should at least fire briefly??
Looking for what to do next....is it time for a new carb or is that even the issue?
Any suggestions appreciated.
Thanks
Your engine is badly flooded, and will take some doing to get it aired out enough to start.

Dump out all of the fuel, and remove the plug, and pull the rope for several dozen times. Then put the plug back on. and hook it all up and try to get it to start, still not putting any fuel in, with the throttle control squeezed/open. Once it gets dried out enough, it will start and run until the excess fuel is burned off.
Then put some fresh fuel in, and try to start as normal.
 

trooper1954

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Thx fish...this actually what I did at the same time as I took the carb off....tried for several minutes to start it but no go. I think my next step has to be to take the carb off, give it a thoro cleaning and install a carb kit and go from there?
I guess I should check the vent on the fuel cap also? Just thinking here......
 

Fish

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A flooded engine takes a lot more drying than one would think.
 

trooper1954

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Thx Fish....I'll take the plug out and pull a few dozen times.....then leave it overnight in the heated shop upside down.
Then another try tomorrow I guess.
 
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