EFI Fuel Pump Failure Risk

[dmattmul]

Since we are talking about Walbro pumps, Walbro includes a thick rubber outer casing that comes with their in-line pumps we use. I guess that is for sound proofing. Both EFII and SDS ship their rack without this casing. Anyone try this? I don't want to create unintended consequences.

 

[FinnFlyer]

Be aware that stat-o-seals come in a variety of different metal rings and a variety of different elastomers. Some elastomers are completely incompatible with ethanol fuels and some even incompatible with 100ll. I found Viton the best elastomer to use for our fuel systems. The problem is some suppliers state Viton and it's not true Viton but something that looks and feels like Viton. If you purchase these, make sure you test in your fuel type being used. Warming the fuel to 120 F and let sitting overnight and watch for swelling seems to work.

This brand I found works and tested well. (SS ring and Viton elastomer)

Thanks. I bought ten for $10 and used four. I could dig up the unused and test one. However haven't seen any leaks there for 100+ hours.

BTW, another name is Banjo Bolt Sealing Washers (name on eBay when I bought them).

 

[dmattmul]

Thanks. I bought ten for $10 and used four. I could dig up the unused and test one. However haven't seen any leaks there for 100+ hours.

BTW, another name is Banjo Bolt Sealing Washers (name on eBay when I bought them).

Just be careful if one starts to "leak" it will not leak fuel but pull air into the pump if the "leak" occurs on the suction side of the pump. Pretty hard to see as their will be no blue staining or smell. This will throw off your AFR but the worst part will damage the seat on the FPR over time.

 

[bakercdb]

Since we are talking about Walbro pumps, Walbro includes a thick rubber outer casing that comes with their in-line pumps we use.

The Pierburg pump that Hirth uses has that thick rubber housing. It worked well for my application and I don’t see any negative consequences. Obviously provides some great vibration isolation and there are no heat issues with fuel flowing through..

200hrs so far. Someone like Ross probably has many more data points than my one., but fwiw.. (I do run the pump at 10.0 V as the 100 lph liter is 3 to 4X my needs and I couldn’t find a quality smaller pump to replace the factory issued one. I did testing at lower volts to see an acceptable range as that type of pump doesn’t like too low voltage. IIRC, just under 9.0 V which where the pump started not running smoothly. (I do have a double throw switch to run it system volts in case of the voltage regulator failure).