B&S 190cc Pressure washer motor runs VERY rich


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Old 04-18-21, 08:43 AM
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B&S 190cc Pressure washer motor runs VERY rich

Hi, New to the forum here. I hope I am playing by the rules...
Here goes,
I have a B&S 675 series pressure washer.
Motor details: 7BSXS 1901VH 277307 engine. 126T02-0131 B1 07042756 code.
Issue - motor runs extremely rich.
Back story:
So - I picked up this pressure washer on the side of the road. Got it home and proceeded to get it running. I got the motor running by pulling off the exhaust muffler and the air cleaner housing. I'm running open air to the carb and open exhaust to the air. The motor runs great. Washes stuff, etc...
My issue is there is no carb adjustment needle that I can find. I pulled the carb apart, cleaned and put it back to gather, but no adjustments I can find. I guess my questions are:
1 - could the motor be fitted with a high altitude jet or maybe the existing jet is worn? if so what jet should I be looking for?
2 - Can I backdate the carb to a previous carb with an adjustment needle? What carb would this be or what motor do I have to pull from?
3 - Am I missing something?
Thx.
 
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Old 04-18-21, 04:02 PM
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The first thing I would look at would be the choke - if it's releasing to "off". The second would be the inlet valve to the float bowl - it may not be sealing and the bowl is overfilling.
 
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Old 04-18-21, 07:05 PM
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Thank you!

Thanks for the ideas. I’m positive the choke is working properly. The float bowl is in good repair and the needle seems to be brand new. The carb looks like it was rebuilt by the previous owner and they gave up. I’ll troubleshoot the float valve to assure it seals properly. Any thoughts on what the diameter of the jet should be? Thanks again.
 
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Old 04-18-21, 07:21 PM
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I couldn't say about the jet size but if it's a brass jet the chance of it being worn when just subjected to gas flow, would be practically zero.
 
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Old 04-18-21, 08:03 PM
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Yes I agree about the jet not wearing due to gas

Yeah, the idea that a jet would wear strictly due to gas flow doesn’t make sense to me either. I’ll pull the carb off and check that float needle again. Maybe I missed something. It’s one of those all plastic floats, maybe the plastic warped. I’ll double check that it shuts off properly. Bums me out there isn’t an adjustable needle on the carb but then it probably wouldn’t have been on the side of the road either...
 
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Old 04-19-21, 04:28 AM
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Let's see if Cheese or one of the shop guys weigh in on this. That particular carburetor may be subject to a leak at some other point.
 
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Old 04-19-21, 05:15 AM
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First thing that comes to my mind is, with it running, I would try a couple squirts of carburetor cleaner of WD40 at the base of the carburetor, where it attaches to the engine. If doing this affects the engine in any way it would indicate a bad gasket or other leak. And by the way, you probably don't want to run it for very long without water or you could damage the pump and it would become a moot point.
 
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Old 04-19-21, 06:39 AM
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Thanks for the input and help everyone. If/when I can return the favor I certainly will.
So... Currently I'm running open air to the carb and open air to the exhaust. If either the air filter or muffler is installed the motor chokes out immediately. With open air, the motor runs strong. I washed my car and driveway with no issue. The motor loads well and idles well. The major issue is the gas particulates spitting out of the carb throat into the open air and the loudness due to no muffler. thoughts?
Thx...
 
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Old 04-19-21, 09:02 AM
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You might check the valve clearance on that engine to see if it's adjustable. What you described in the gas spitting out of the carb throat is more intake valve oriented than carburetion.
 
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Old 04-19-21, 10:38 AM
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I'll do a compression check.
When I pulled the head cover off and checked the valves and piston condition things didn't look crooked...but I didn't do an actual compression check. Guess I jumped that step. Thanks.
 
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Old 04-19-21, 10:13 PM
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I agree, it shouldn't be spitting gas out. Is it smoking while running? A rich condition bad enough to choke the engine out should be making black smoke. Putting a muffler on shouldn't be able to stop the engine unless it's clogged.
 
 

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