Mapletech
New Member
I have heard that the pre filter height is important, can any body tell me the correct height and why it is important. Thanks D
Diesel Pre Filters
- Thread starter Mapletech
- Start date
Kawasaki
Well-Known Member
If the Pre filter is gravity fed, it needs to be lower than the fuel tank.
Mapletech
New Member
The lift pump on the engine will surely pull the fuel up from the tanks through the filter NO ?
Kawasaki
Well-Known Member
Yes but it's better if it doesn,t have to.
What boat and engine are we talking about?
More info would be better.
Some installations have a pump on the pre filter and the engine.
Came across a boat last week which only had a 'pump'on the filter!
What boat and engine are we talking about?
More info would be better.
Some installations have a pump on the pre filter and the engine.
Came across a boat last week which only had a 'pump'on the filter!
volvopaul
Well-Known Member
Builders stick them anywhere usually where you cant get to them when you need to like in a rough sea when your on one engine rolling around.
It ceases to amaze me when you look in the engine bay and see a suitable spot and its not there.
The engine lift pump will suck the fuel through, I like builders that place them high up so that when you change the filter and the tanks are nearly full, diesel doesnt spill out of the housing.
I must admit and its on the job list my prefilters are set under the floor rear of engine room and leak fuel all over when you screw them off.
It ceases to amaze me when you look in the engine bay and see a suitable spot and its not there.
The engine lift pump will suck the fuel through, I like builders that place them high up so that when you change the filter and the tanks are nearly full, diesel doesnt spill out of the housing.
I must admit and its on the job list my prefilters are set under the floor rear of engine room and leak fuel all over when you screw them off.
DavidJ
Well-Known Member
I suspect on my Sealine S37 (KAD43's) that the pre-filter level is wrong. If I undo the lower nut to drain off any crud and water, I can hear it sucking air in. In consequence I don't bother and just replace every year. Is this a symptom of them being installed too high?
Mapletech
New Member
You need to close the inlet and outlet valves, then loosen the bleed screw on top before opening the drain at the bottom, otherwise yes you will get the fuel flowing back to the tank and sucking air in through the drain.
The filters I am refering to are Separ and fitted to a Rampage 38 sport fisher with C9 Cat engines approx 575 HP
The filters I am refering to are Separ and fitted to a Rampage 38 sport fisher with C9 Cat engines approx 575 HP
DavidJ
Well-Known Member
[ QUOTE ]
You need to close the inlet and outlet valves, then loosen the bleed screw on top before opening the drain at the bottom, otherwise yes you will get the fuel flowing back to the tank and sucking air in through the drain.
The filters I am refering to are Separ and fitted to a Rampage 38 sport fisher with C9 Cat engines approx 575 HP
[/ QUOTE ]
Thanks, although mine are Fleetguard filters the principal that you outline will be the same....I'll try that.
You need to close the inlet and outlet valves, then loosen the bleed screw on top before opening the drain at the bottom, otherwise yes you will get the fuel flowing back to the tank and sucking air in through the drain.
The filters I am refering to are Separ and fitted to a Rampage 38 sport fisher with C9 Cat engines approx 575 HP
[/ QUOTE ]
Thanks, although mine are Fleetguard filters the principal that you outline will be the same....I'll try that.