andrewslarge
Well-Known Member
Definitely can be leaking by the cover. I think you’re getting closer to the issue.
Could of tested the pulse hose for free. How is that? Plug one end and blow in the other.Local shop had an impulse line in stock and went and got one. Installed it and is snug now. Pushed the pump on and no difference. I'll post what happens with the new pump when it arrives.
I did test the hose using that method only with vacuum if you read above. These seal with an internal groove into the rocker cover and it spun easy so I thought maybe it was drawing air in there. You have tested one like that? Maybe you are assuming it was just a hose with push on fittings.Could of tested the pulse hose for free. How is that? Plug one end and blow in the other.
Stop buying untested new parts and test what you have. New doesn't mean new anymore.
Yes, Mikuni fuel pumps are frequently counterfeited, along with other Mikuni components like carburetors. These imitation pumps, often originating from China or sold as generic alternatives, are prevalent on marketplaces like eBay and Amazon. [1, 2, 3, 4]
Key Information on Counterfeit Mikuni Pumps
- Quality Issues: Imitation pumps are described as "junk" by some users, with poor-quality diaphragm materials that may not last as long as genuine Mikuni Japan components.
- Identifying Fakes: While genuine Mikuni pumps are made in Japan and often carry the "MIC" or "Mikuni" mark, counterfeiters are becoming better at reproducing packaging and branding.
- Aftermarket Brands: Some, like Sports Parts Inc. (SPI) or others mentioned as "Winderosa" or "Nachman," are sold as aftermarket alternatives, but some sellers may falsely list them alongside genuine photos.
- Performance: Counterfeit pumps may cause fuel delivery issues, similar to how counterfeit carburetors cause, leading to engine issues. [1, 2, 3, 4, 5]
I did all could on the last one that failed. Went to a dealer and bought one that came in a Briggs box. Like I said, I paid more than what they were online. Maybe they are selling knockoffs too but easy for manufactureres to fall back on that when they themselves have issues. I bought an obvious knock off this time so we'll see if it is any better. If it fails, I'm going with an electric.According to Google AI
Missed the part where you tested it.I did test the hose using that method only with vacuum if you read above. These seal with an internal groove into the rocker cover and it spun easy so I thought maybe it was drawing air in there. You have tested one like that? Maybe you are assuming it was just a hose with push on fittings.
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