[Z06] Walbro 450 install w/hydramat
08-29-2016, 11:45 AM
#1
Safety Car
Thread Starter
Walbro 450 install w/hydramat
There are some other posts on this, here is yet another take.
I am using a separate fuel filter and fuel pressure regulator, so this is obviously a bit different.
The Hydramat you want to use is Part # 16-111.
Here is a general overview (the order of operations is important) and the pics are below
1 - first step is to disassemble the lower bucket (3 tabs, easy) and then remove the pump (there is a raised lip on the inside of the bucket, firmly wiggle the pump upwards, it will eventually come up)
2 - remove the OEM fuel filter and the fuel pressure regulator. The OEM fuel filter is in the cylinder near the top, there are tabs that very firmly hold the upper and lower pieces in place. You can either pry the tabs or just cut the tabs. FPR retainer is held in by 4 tabs, relatively easy to undo those
3 - cut the OEM fuel hose and fuel pump wiring (leave at least 4" on there)
4 - Remove the old pump from the OEM plastic sleeve, swap in the new pump.
4.5 - cut slots in the plastic piece (in which the pump sits) to allow the plastic piece to slide all the way to the bottom of the bucket
5 - Test fit new pump, approximate where the pump inlet sits at the bottom of the bucket (it is directly opposite the outlet). Drill a 1.25" or so hole (with a unibit). Test fit the Hydramat, in the intended orientation, to confirm that the hole is big enough to accommodate the plastic retaining tab. Note that I trimmed all but two of the retaining tabs off the hydramat piece as they are not needed.
6 - drill holes in the pump mount piece (the piece that the rubber piece with 3 mounting tabs sits in) to hold the mount in place. The pump inlet should be sticking through the ~1.25" hole you just drilled. You will need to use either flush or shallow head screws. You will need to drill these holes in the 2 indentations on the lower bucket or else the screw heads will stick out and not allow the bucket to fit back into the tank.
6.5 If you are using the OEM fuel pressure regulator, drill holes in the side of the bucket, above the plastic piece that you secured in place. This will allow the fuel to spill out of the bucket sooner, down to the pickup. If you are not using the OEM fuel pressure sensor, you will need to add a return fitting to the top of the tank. Pick a flat area (flat on the inside of the tank and the outside - the tank is very thick and thus curves begin sooner on the inside than on the outside), then drill a 3/4" hole and use Parker stat-o-seals and threadseals to seal the bulkhead fitting.
7. Put the pump (w/plastic sleeve w/the rubber mounting piece) into the plastic mount that you just secured to the bucket. Snap the lower bucket back together. Note that at this point there is nothing securing the pump, other than gravity. Test fit the bucket/Hydramat combo to determine which mounting tab you want to use and mark the tab.
7.5 - install new corrugated in-tank fuel hose on the pump outlet. I used Flex-10-240 (240mm long, 10mm diameter) from APEUSA.com. $5. Slide on without much fuss and I secured it using an Oetiker clamp.
8. I clipped off the remaining tabs - be careful as the pieces fly and you don't want to clip off the the tab you are going to use. You can also cut off the other pieces with a dremel (though be sure the Hydramat remains in plastic and you keep the dust away from it).
9. Press the hydramat onto the pump - you will need to firmly press and wiggle on the plastic retainer and the fitting that goes over the inlet.
10. I am using 8AN fittings - so I drilled out the OEM outlet with a 3/4" unibit and cut the remaining raised portion with a razor (you want the smoothest surface possible, for sealing purposes). I then installed a 90 degree 8AN fitting using a Parker stat-o-seal on top and a Parker threadseal washer on the bottom (i.e., in the top of the old filter bucket - obviously you will need to dremel out the strengthening ribs) for the threadseal washer to fit). I then put a 3/8" nipple to 8AN adapter on the end of that fitting
11. I crimped together the wire from the pump and the OEM in-tank harness and covered the connection with viton heat shrink. You need something that can live in gas/ethanol - viton or kynar will work. If you are adding any wiring, ensure that it has teflon insulation. Ensure that you include some extra length of wire and sure that the wire is secured and won't get caught in the fuel level sensor.
12. Press on the other end of the fuel hose to the 3/8" adapter on the top of the assembly and add an Oetiker clamp.
13. Re-install the fuel level sensor assemble
14. Snap together the upper and lower bucket and install into the tank. You will need to fold the hydramat downwards (under the bucket).
I am using a separate fuel filter and fuel pressure regulator, so this is obviously a bit different.
The Hydramat you want to use is Part # 16-111.
Here is a general overview (the order of operations is important) and the pics are below
1 - first step is to disassemble the lower bucket (3 tabs, easy) and then remove the pump (there is a raised lip on the inside of the bucket, firmly wiggle the pump upwards, it will eventually come up)
2 - remove the OEM fuel filter and the fuel pressure regulator. The OEM fuel filter is in the cylinder near the top, there are tabs that very firmly hold the upper and lower pieces in place. You can either pry the tabs or just cut the tabs. FPR retainer is held in by 4 tabs, relatively easy to undo those
3 - cut the OEM fuel hose and fuel pump wiring (leave at least 4" on there)
4 - Remove the old pump from the OEM plastic sleeve, swap in the new pump.
4.5 - cut slots in the plastic piece (in which the pump sits) to allow the plastic piece to slide all the way to the bottom of the bucket
5 - Test fit new pump, approximate where the pump inlet sits at the bottom of the bucket (it is directly opposite the outlet). Drill a 1.25" or so hole (with a unibit). Test fit the Hydramat, in the intended orientation, to confirm that the hole is big enough to accommodate the plastic retaining tab. Note that I trimmed all but two of the retaining tabs off the hydramat piece as they are not needed.
6 - drill holes in the pump mount piece (the piece that the rubber piece with 3 mounting tabs sits in) to hold the mount in place. The pump inlet should be sticking through the ~1.25" hole you just drilled. You will need to use either flush or shallow head screws. You will need to drill these holes in the 2 indentations on the lower bucket or else the screw heads will stick out and not allow the bucket to fit back into the tank.
6.5 If you are using the OEM fuel pressure regulator, drill holes in the side of the bucket, above the plastic piece that you secured in place. This will allow the fuel to spill out of the bucket sooner, down to the pickup. If you are not using the OEM fuel pressure sensor, you will need to add a return fitting to the top of the tank. Pick a flat area (flat on the inside of the tank and the outside - the tank is very thick and thus curves begin sooner on the inside than on the outside), then drill a 3/4" hole and use Parker stat-o-seals and threadseals to seal the bulkhead fitting.
7. Put the pump (w/plastic sleeve w/the rubber mounting piece) into the plastic mount that you just secured to the bucket. Snap the lower bucket back together. Note that at this point there is nothing securing the pump, other than gravity. Test fit the bucket/Hydramat combo to determine which mounting tab you want to use and mark the tab.
7.5 - install new corrugated in-tank fuel hose on the pump outlet. I used Flex-10-240 (240mm long, 10mm diameter) from APEUSA.com. $5. Slide on without much fuss and I secured it using an Oetiker clamp.
8. I clipped off the remaining tabs - be careful as the pieces fly and you don't want to clip off the the tab you are going to use. You can also cut off the other pieces with a dremel (though be sure the Hydramat remains in plastic and you keep the dust away from it).
9. Press the hydramat onto the pump - you will need to firmly press and wiggle on the plastic retainer and the fitting that goes over the inlet.
10. I am using 8AN fittings - so I drilled out the OEM outlet with a 3/4" unibit and cut the remaining raised portion with a razor (you want the smoothest surface possible, for sealing purposes). I then installed a 90 degree 8AN fitting using a Parker stat-o-seal on top and a Parker threadseal washer on the bottom (i.e., in the top of the old filter bucket - obviously you will need to dremel out the strengthening ribs) for the threadseal washer to fit). I then put a 3/8" nipple to 8AN adapter on the end of that fitting
11. I crimped together the wire from the pump and the OEM in-tank harness and covered the connection with viton heat shrink. You need something that can live in gas/ethanol - viton or kynar will work. If you are adding any wiring, ensure that it has teflon insulation. Ensure that you include some extra length of wire and sure that the wire is secured and won't get caught in the fuel level sensor.
12. Press on the other end of the fuel hose to the 3/8" adapter on the top of the assembly and add an Oetiker clamp.
13. Re-install the fuel level sensor assemble
14. Snap together the upper and lower bucket and install into the tank. You will need to fold the hydramat downwards (under the bucket).
Last edited by RX-Ben; 08-29-2016 at 11:47 AM.
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