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General Category => Tech Corner => Topic started by: Spurlock on July 26, 2020, 12:14:30 PM



Title: Installing a Facet solid state electronic fuel pump
Post by: Spurlock on July 26, 2020, 12:14:30 PM
After reading stories about fuel pump fires likely caused by arcing of the pump's mechanical contact points, and knowing my pump was 31 years old and no longer available I decided to upgrade to something that is easily available and reliable. I had previously replaced the contact points in my OEM pump as a precaution, but I thought it better to replace the old pump which was likely to fail someday from old age. So after a bit of internet reading I discovered that a popular upgrade for the old mechanical contact diaphragm pumps is the Facet 40171 electronic fuel pump. These use solid state switching instead of mechanical points and are a popular retrofit on many bikes, especially the KTM 950. They are also popular with small kit aircraft builders so I figured that speaks to their reliability. I bought mine from Aircraft Spruce & Specialty Co. in S. California. https://www.aircraftspruce.com/catalog/eppages/facetpumps.php?clickkey=50245 (https://www.aircraftspruce.com/catalog/eppages/facetpumps.php?clickkey=50245)

The Facet installed fairly easily and works very well. For comparison here is the original pump and filter arrangement:

(https://photos.smugmug.com/Motorcycles/CB-1-Fuel-pump/i-k47sp9f/0/2b9671a5/O/DSC02403.jpg)

This is the Facet 40171. It has female 1/8 pipe threads for the inlet and outlet, so I added a 3/8" barbed fitting to the inlet to match the 10 mm fuel filter nipple and a 5/16" barb to the outlet to match the 8 mm fuel line to the carbs.

(https://photos.smugmug.com/Motorcycles/CB-1-Fuel-pump/i-WHMVw4J/0/081ab42f/O/DSC02405.jpg)

I then sawed off part of each mounting bracket and drilled a hole on the remaining tab for zip ties.

(https://photos.smugmug.com/Motorcycles/CB-1-Fuel-pump/i-ZSTG4vN/0/9ecd95a4/O/DSC02407.jpg)

I added 5 mm thick self adhesive foam to the inside of the original pump frame bracket. The Facet was then a snug fit in the U of the bracket. I bent the mounting tabs downward and used zip ties down to the original bracket. Here is a top view -

(https://photos.smugmug.com/Motorcycles/CB-1-Fuel-pump/i-bqDbvQP/0/626e9159/O/DSC02411.jpg)

and the side view-

(https://photos.smugmug.com/Motorcycles/CB-1-Fuel-pump/i-BbqhpDx/0/64622524/O/DSC02415.jpg)

I needed a single U-bend 10 mm hose to go between the filter and the pump. This universal molded fuel line had the section I needed:  https://www.ebay.com/itm/Universal-3-8-Molded-Fuel-Line-Cut-Your-Own-Rubber-Hose-Elbow-45-90-180-10mm/152827803323?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 (https://www.ebay.com/itm/Universal-3-8-Molded-Fuel-Line-Cut-Your-Own-Rubber-Hose-Elbow-45-90-180-10mm/152827803323?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649)

(https://photos.smugmug.com/Motorcycles/CB-1-Fuel-pump/i-3t78KQ7/0/e0679fd7/O/DSC02417.jpg)

Finding room for the filter was tricky. I trimmed the lower left corner of the battery box to better clear the hose but that is not strictly necessary.

(https://photos.smugmug.com/Motorcycles/CB-1-Fuel-pump/i-JHSCGn8/0/74eb6467/O/DSC02419.jpg)

Here is the completed installation. I had to reverse the fuel filter and put the larger end w/metal ring as the inlet in order to fit. A smaller filter would make things easier but this works fine. The filter is zip tied to the frame and rests on rubber foam on top of the pump. From the petcock the fuel line makes a short straight run to the filter, then a U bend connects to the pump. The pump outlet aligns perfectly with the original carb supply line. The pump has built in shutoff and anti-siphon valves to prevent fuel flow when turned off. Flow is way more than adequate and pressure is 2-3.5 psi so there is no problem overpowering the float valves. After all, this pump is specifically designed for carbureted engines.

(https://photos.smugmug.com/Motorcycles/CB-1-Fuel-pump/i-jNCvKWx/0/db3ba53a/O/DSC02423.jpg)

-Bill


Title: Re: Installing a Facet solid state electronic fuel pump
Post by: stussels on July 29, 2020, 10:09:31 PM
nice to see this documented.  makes me wish i wouldve waited but i bought a nos pump from a seller in isreal a while back. 


Title: Re: Installing a Facet solid state electronic fuel pump
Post by: Spurlock on July 29, 2020, 10:23:37 PM
nice to see this documented.  makes me wish i wouldve waited but i bought a nos pump from a seller in isreal a while back. 

Lucky find, that NOS pump should be all you ever need.

-Bill


Title: Re: Installing a Facet solid state electronic fuel pump
Post by: stussels on August 09, 2020, 10:21:16 PM
it is replacing the original hehe