This picture shows the fuel canister opened up. The yellow 3/8 ID hose is the new larger fuel pickup, the gray unit at the bottom is the replacement spacer, it has an ID of 1/2 inch, the gray section is a 3 inch section (I think, may have been 4 inch?) of threaded PVC 3/8 water pipe (from the lawn sprinkler section of the home improvment store), the white sections on both it's ends are lath-turned units made by gluing up verious PVC fitting parts and then turning them to shape and length once they were tightly screwed onto the gray PVC pipe nipple.
2_-_replacement_center_pickup_removed_from_pickup_unit.JPG (34 Kb, 88 downloads)
The bottom portion of this picture shows the stock spacer with the stock tiny plastic fuel hose attached. They used the upper section of the white spacer as the hose barb, the fuel opening I.D. where the hose attaches to this spacer is only a few thousants larger than 1/8 inch.
The upper part of the picture shows my replacement parts. The new PVC spacer has an I.D. of 1/2 inch up to the nylon hose barb, the hose barb has an I.D. of 3/8 inch, as does the yellow hose. I used a heat gun to soften the hose a bit so it would fit over the hose barb.
The smallest I.D. in the entire new fuel line setup is in the made-up hose barb seen on the output of the 90 degree pipe fitting, this is made from steel 3/8 brake tubing and has an I.D. of just a few thousanths larger than 5/16 inch. I used this type of hose connection here because it is a bugger to get to when dropping or installing the fuel tank, this type connection does not hold on to the modern rubber 2-layer fuel hose like a barbed fitting does so it is much easier to remove or install the hose.
3_-_stock_and_new_fuel_pickup_units.JPG (34 Kb, 68 downloads)
This is a closer look at the stock and replacement spacers. I glued up verious fittings to get the length and diameter needed for both the top and bottom end of the spacer then turned them to the same dimensions and length as the stock spacer, this allowed the slip-on stock plastic spacer thingies to end up in the correct place inside the fuel pickup canister.
4_-_closer_view_of_stock_and_new_pickups.JPG (26 Kb, 57 downloads)
This shows the canister spacers in place on the stock spacer.
5_-_stock_pickup_with_return_screen_and_spacer.JPG (41 Kb, 48 downloads)
This shows the same canister spacers in place on the new spacer.
6_-_new_pickup_with_return_screen_and_spacer.JPG (30 Kb, 43 downloads)
This is an end-view comparison of the openings up through the stock and new fuel pickup spacer.
9_-_bottom_view_of_stock_and_new_pickups.JPG (45 Kb, 40 downloads)
This shows the 3/8 I.D. nylon hose barb. The bottom of the barb is threaded and I threaded the white PVC fitting to match.
10_-_3-8_nylon_hose_barb_in_new_pickup.JPG (18 Kb, 38 downloads)
this closeup shows the shape of the fitting on the bottom of the new spacer. Just for extra safty I uses poleyester epoxy as a thread sealent, it does not bond to PVC but makes a good sealent.
12_-_lower_end_of_new_pickup.JPG (13 Kb, 28 downloads)
This shows the upper end of the yellow hose. The larger diameter plastic fitting with the exposed barbs is the stock filler plug that was in the top of the pickup canister. It originally was a solid filler plug but I drilled it to use as the new larger fuel outlet. I used a hole saw and made an extra 1/8 inch thick ABS plastic washer to fit up inside this filler plug, it added stiffness to the top surface of the plug and also added thickness. There is another 3/8 I.D. nylon hose barb screwed up through a hole in the center of this stiffener/spacer washer and the filler plug, the hose barb screws up tightly into the bottom of the 90 degree pipe fitting to hold everything together.
13_-_new_3-8_outlet_-_hose_and_fitting.JPG (41 Kb, 31 downloads)
Side view of the same fitting.
14_-_new_3-8_hose_and_fitting-side_view.JPG (31 Kb, 29 downloads)
This is a top view of the fuel canister showing the new larger fuel outlet, I blocked off the original small fuel outlet fitting with a bit of fuel hose and a bolt for a plug. I use the stock fuel return as it has a duckbill check valve just under the top of the canister upper surface, the factory did it that way for some unknown reason so I decided to use the same return connection.
15_-_top_view_of_modified_fuel_pickup_unit.JPG (37 Kb, 37 downloads)
This is an end view of the 2-layer 3/8 I.D. plastic yellow air hose. It is rated for petro-products, 160 deg f temps, and 300 pounds pressure (from memory), I have had sections of this immersed in all sorts of fuels and blends for a couple years and none of the samples show any degridation.
17_-_air_hose_for_fuel_line.JPG (8 Kb, 42 downloads)
This shows the inside of the red strainer basket that fits on the very bottom of the fuel pickup canister. I cut away the very tiny plastic screen that was originally between the outer segments of the small red dividers on the very bottom of this unit, I then added a round section of window screen inside it. The extremely fine mesh of the original screeing material was just too fine to allow thick cold oil to flow through it fast enough. Once this unit is snapped back on to he canister the window screen is trapped in place.
18_-_screen_-_top_view.JPG (42 Kb, 34 downloads)
This shows the bottom of the spacer unit that fits on the bottom of the fuel pickup spacer, this red spacer actually contains a check valve for the fuel inside the fuel canister. If you look close you can see a small round disk (red on red), this is the bottom part of the flexible plastic check valve. The engine return fuel runs into the inside of the fuel pickup canister and fills the canister with fuel, if the fuel tank is nearly empty and you are making a turn, or climbing a hill, and there is not enough fuel in the tank to cover the bottom of the fuel pickup, the float that is below this check valve unit drops down and allows the plastic valve to open due to the weight of the fuel above it, the fuel drains out of the canister through this check valve and into the bottom of the fuel pickup spacer.
20_-_return_screen_-_bottom_view.JPG (34 Kb, 38 downloads)
This shows the other side (upper side) of the same spacer, the dark area is the same very fine screen material found on the bottom screen unit, I couldn't figure a way to replace this with courser screen and since the fuel returning into the canister from the engine is now a bit warmer it seems to work OK as-is.
23_-_return_screen_-_45_top_view.JPG (33 Kb, 31 downloads)
Edge view of same spacer.
22_-_return_screen_-_45_bottom_view.JPG (28 Kb, 26 downloads)
This shows the hockey-puck sized float unit that sits inside the red filter screen basket on the bottom of the fuel canister. You can see another plastic check valve in the center of this unit, it is part of the "almost empty tank" device to feed fuel from inside the fuel canister. It the fuel in the tank moves away from the fuel canister this check valve drops down and closes to keep the fuel from the canister from draining out into the tank, the float drops down and allows th red check valve to open and drain fuel from the inside of the canister onto the top of the float and into the bottom end of the fuel pickup spacer.
25_-_float_-_45_top_view.JPG (20 Kb, 33 downloads)
This shows the bottom of the float, you can see the three oblong openings that allow fuel from the tank to flow up through the check valve and into the bottom of the fuel pickup when the tank has fuel in it. It was the gray area in the center, plus the openings, that was packed with the thick gray putty stuff that caused me to not be able to draw fuel from the tank once the weather turned cold last fall. Don't know just where it came from ,and there was only maybe a half-teaspoon of it but once it got cold it sure clogged up the fuel flow. I suspect the gunk was created from some sort of reaction between something in my blend and the galvinize inside the 90 deg pipe fitting I used as the outlet from the tank, don't know, just hope it doesn't happen again?
26_-_float_-_bottom_view-_3_openings_shown.JPG (26 Kb, 27 downloads)
OK - now about the fuel sender unit. There are different types of these apparently? The one on this canister can be completely disassembled with out the need of tools.
This picture shows the entire sender removed from the fuel pickup unit.
complete_sender.JPG (27 Kb, 46 downloads)
You remove the wire float arm from the plastic post of the sender by firmly lifting it up and back over the center post that the loop on the end of the wire arm is attached to. The wire loop is not welded closed so it will give a bit and pop over the protrusion on the end of plastic center post.
Once the wire arm is removed it releases the pressure on the plastic float mounting arm and this plastic arm can be slid up and off the center pivot point. Then you use a small punch and push the metal center post that everything pivots on out the back of the unit. Now you can rotate the sliding contacts farther than normal, this allows a tab on the plastic center unit to move out from under a grove in the main sender housing, the plastic center section and the sliding contacts can then be totaly removed from the sender.
The center electrical contact of the sender is the contact for the sliding contacts, this SS tab can be removed from the sender body once the sliding contacts are removed. Mine had what lookes like a gouge where the sliding contacts mate to it, This gouge is not caused by ware of the moving contacts, it is apparently needed to make good contact, be sure to put this SS contact tab back together with the gouge on the same side that it was on when you removed it.
The ceramic board that makes contact with the sliding contacts can now be removed by gently prying back the two plastic tabs located against the inside edge of the ceramic board and at the same time pushing up a bit on the back of the board. Once the tabs allow the board to raise up a bit you slide the board sideways just a bit and it will come out of the sender.
This ceramic board looks fragile but is surprisingly tough, I pried pretty hard on things and it survived just fine.
I used laquor thinner to clean up the ceramic board and the sliding contacts, then I used a pencil eraser to clean the heavy crud off both the sliding contacts and the printed contacts on the ceramic board.
This sender has always been erratic with veg, I think the thick oil gets between the contacts and acts as an insulator. I bent the arms of the sliding contacts down at almost a 90 deg angle to increase the contact pressure. The arm material of these contacts look like brass but is something much tougher, it took a lot of bashing and bending and finally formed up just fine.
Put it all back together and adjust the position of the small plastic float arm before installing the wire loop of the float arm back over the post, the wire loop squeezes down on everything and keeps the plastic arm from coming out of adjustment
This picture is of the plastic float arm
float_mountig_arm_-_removed_from_sensor.JPG (6 Kb, 41 downloads)
|Powered by Social Strata||Page 1 2 3 4 5 6 7|