Hey Guys,
We wanted to offer some tech advice for our DW301 fuel pump based a few customers we have assisted and recent testing we've done.
Installation:
When installing the DW301 we recommend using the OE spacer and grommet/seal from the OE pump. We have tested this in an EVO 8/9 fuel pump assembly and it holds pressure to over 100psi w/o bleeding off. See picture below:
If you are removing a Walbro pump to install your DW301 and you used the o-ring provide with the Walbro kit, we DO NOT recommend re-using this on your DW pump. Replace with the OE spacer and grommet/seal. We have tested the Walbro seal on the DW pump installed in a EVO 8/9 assembly, there is some pressure loss at 50psi and massive pressure loss above 70 psi. If you don't have your OE grommet/seal, contact us and we will send you a better o-ring solution. See picture below of an alternative to the Walbro seal or OE grommet/seal:
Lastly, if upon installation you are not getting fuel pressure and the car will not start you may need to prime the system. There could be air in the system causing the pump to vapor lock. This will not always be necessary, but this is the first thing we recommend trying if you are not getting pressure. Please follow the process below:
- Have the pump fully installed in the assembly.
- Disconnect the fuel feed line. There are three lines on the top of the assembly; the feed line is the one furthest from the electrical connector.
- Attach a 4 foot, or appropriate length, fuel hose to the feed line and run it to a container next to the car.
- Turn the car over for several seconds until the trapped air is evacuated and fuel comes out of the hose.
Note: turning the key to the “on” position WILL NOT prime the pump. You must turn the car over until the air is pushed out and the is flowing. Then, re-attach the feed line and start the car.
See video below for process of priming the pump if needed. (sorry for the poor quality, we will soon have high quality install video’s on our website)
http://www.youtube.com/watch?v=TblYEKWGruU&hd=1