Topic Filter
In recent years, the subject of filters has become increasingly important and is certainly one of the most important reasons for a functioning system with the HARDI pump. Basically, for us the correct line away from the tank is as follows....
TANK >>>>PREFILTER>>>>>HARDI-PUMP>>>>>CARBURETOR
Thus, our preference is no filter in front of the carburetor. Our HARDI pump works with the back pressure of the carburetor and therefore obstacles (like the filter) are counterproductive regarding the proper function of the HARDI pump. Through many conversations with customers we know that systems can still work (i.e. even with a filter in front of the carburetor). However, we want to talk about the optimal installation here....
We have tested about 15 different small filters in the last 7 years and can only really recommend the following filters with a clear conscience. The experience is basically with all "bad" filters that too much power and thus flow rate is taken from the pump. This in turn can lead to under-delivery of fuel in some cases.
Likewise, we always point out that the HARDI pump should also be protected from dirt. However, this does not mean that a filter is installed before and after the pump. This would also be counterproductive and the system with the HARDI pump would probably not work for long.
Now here are the filters that passed our test as successful. The loss of flow rate was about 5-8L/h
Fuel filter 8mm from Pierburg 4.00030.80.0
Fuel filter 6/8mm from Mahle Knecht KL 63 OF
Fuel filter 8/10mm from SF SK3759
From our point of view, changing these filters once a year/season is enough and everything should be fine...you don't need anything more, not even anything that is more expensive....
