Prefill Filters

Stmar

Active member

Equipment
B2650HSDC
May 23, 2017
906
42
28
Buffalo, Wyoming
When you service your machine do you fill your filters before you install them? I saw a video and a guy was doing that and I had never heard of that procedure. Just wondering if I was missing something.
 

85Hokie

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Staff member
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,423
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113
Bedford - VA
When you service your machine do you fill your filters before you install them? I saw a video and a guy was doing that and I had never heard of that procedure. Just wondering if I was missing something.
I can understand the logic behind it, but I never do - and on most cars/trucks/tractors they are mounted horz - thus you will waste some oil when getting it started. On subaru's they filter is mount vertical, that will make a hellva mess! Those that hang vertical and opening up - I can see filling it.

The check oil light will come on for about 3 seconds, until full. The engine will not have any ill effects - there is still oil between the parts, a thin film still.
 

Stmar

Active member

Equipment
B2650HSDC
May 23, 2017
906
42
28
Buffalo, Wyoming
I was thinking same thing, mess, and I tend to make enough of a mess without compounding the issue. Thanks.
 

windzer

New member

Equipment
Bx2370-1
Dec 8, 2015
82
0
0
Illinois usa
Yes u can if the oil filter is vertical but nowadays for fuel filters you shouldn't because the hole you pour fuel In on the filter is actually the clean side most fuel filters any more say do not fill on The side at least for bigger equipment
 

Daren Todd

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Lifetime Member

Equipment
Massey Ferguson 1825E, Kubota Z121S, Box blade, Rotary Cutter
May 18, 2014
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Vilonia, Arkansas
Depends on the equipment and how fuel system is set up. Most of the time it's not necessary. Especially on modern equipment.

New equipment usually has an electric fuel pump. So the process for priming the system is extremely simple.

Also as brought up by another member that you can be adding contaminants straight to your injection pump.

On modern common rail systems, quite a few have a pressure relief valve (prv) that can be quite expensive to replace. On green engines, the prv can cost around $900 :eek:

My advise is to NOT prefill your fuel filters. Just follow the instructions in the manual if your system has a manual fuel pump. If it has an electric fuel pump, priming the system is a matter of turning on the key and count to 20 ;)

Sent from my SM-G920V using Tapatalk
 

Stmar

Active member

Equipment
B2650HSDC
May 23, 2017
906
42
28
Buffalo, Wyoming
In my manual when it talks about the hydrostatic filters it says to tighten one a half turn only and the other one a full turn only. How critical is that? Seems subjective as to when it makes contact. My HST was tight at 1/2 turn and the tranny filter may have had a bit more after a full turn. No leaks, just wonder why they put "only" in the manual instructions.
 

redfernclan

Member
Jul 18, 2014
155
4
18
Sweet home, Oregon
Worked as a diesel mechanic for ten years at a saw mill. The only time we pre filled them was on systems that had an issue priming. In other words, not lube oil or hyd. systems. If it's not an issue, don't risk problems by making it an issue. With that being said, we had some older riggs that had trouble priming so we would pre fill the filters. Most of them had priming pumps that were worn out. I remember one model Hyster had the priming pump on one side of the engine and the bleed screw on the other. Got to love them Engineers. On that one we just added an electric fuel pump. Turn the key on, bleed the fuel and start. No issue. I believe that is the way most of the newer tractors are set up. Electric fuel pumps. Bonus is that when the priming or "pick up" pump is worn out, you replace it. On the old one it was a gear pump on the front of the injector pump and you had to have the whole thing rebuilt.
I'm a big fan of not trying to fix a problem that is not there.
 

Stmar

Active member

Equipment
B2650HSDC
May 23, 2017
906
42
28
Buffalo, Wyoming
It would have been hard to pre fill the oil filter, it was a hassle to get lose and to put the new one in. Even if they had rerouted some of that cabling/tubing whatever, instead of stacking it on the filter. A real pain to say the least. I realize there are only so many places to mount things but an oil filter has to be serviced so why not make it convenient. The service guys must be complaining too.
 

whitetiger

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Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
2,614
1,133
113
Kansas City, KS
It is recommended by Kubota to NOT prefill your filters as it can introduce contaminants into the system your trying to keep clean. Its really a foolish practice and most filters do not mount straight down so your dumping the fluid back out while installing it.
Wastes fluids, makes a mess, can contaminate system, pretty much a no brainer.