We were overdue to change our skoolie fuel filter.
And, a couple of weeks ago I ran out of diesel fuel.
I know…I know”¦
Bad skoolie owner! Very bad. Tsk tsk and all that stuff.
I managed to get everything going again, but it still didn’t sound quite right.
I worried that I had damaged the injectors.
Then yesterday it wouldn’t start.
Yikes.
Fuel Line Leak
So I took a look under the hood and found a fuel leak in the line coming out of the fuel filter housing. I had loosened this line to bleed air out of the system in the great Run-Out-of-Fuel-Escapade. I tried tightening the nut to no avail.
So I took off the fuel line. At each end…well, check that, at one end, I found a small rubber grommet that looked like a wide o-ring. At the other end was a black goo formerly known as a grommet.
Aha! I wagered that was the problem. The fuel line was allowing fuel out and air in and the ol’ DT466 didn’t like that.
So I grabbed the fuel line and grommet and scooted on down to the auto parts store. Then another one. Then a truck repair shop. Nobody had it.
Once again I found myself in a project that I hoped would take an hour or so that was turning into much more.
Finally, at an International dealership I found a pair of fuel line grommets for $3.72 apiece. That’s some pricey rubber.
Anyhoo…I scooted on back home, pushed on the grommets, applied some thread sealant and bolted the fuel line back on.
Replacing the Skoolie Fuel Filter
Removing the Fuel Filter
Since I was monkeying around with the fuel system anyway, I decided to replace the old…nay, ancient, skoolie fuel filter. (I had been nervous to attempt this project this summer since I resided a good hour away from civilization.)
Using a filter wrench, I loosened the filter. I probably should have released the pressure through the bleeder valve because I had to crank the filter pretty hard to get it to move.
I triumphed, however, and, trying not to dump diesel fuel all over the ground I lowered it below the frame and off to the safety of the shop.
Installing the New Fuel Filter
I compared the old and new filters. The new one measured an inch or so longer than the old one but matched in circumference…so I thought that looked good. (overly optimistic of me”¦.)
To Pre-fill or Not to Pre-Fill…That is the Question!
Now comes the “Great-Prefill-the-Fuel-Filter-Debate.”
I had read posts and seen youtube videos where many people advocated for filling the filter with fuel before screwing it on. In theory, this strategy reduces the amount of bleeding that you have to do to get air out of the fuel system.
Other posters, however, strongly discouraged this practice. One such discourager stated that he had been trained and worked as an International diesel mechanic. He said that pouring unfiltered fuel into the filter increases the risk of dirt particles making it to the fuel injectors. Since these injectors have such tight tolerances, small dirt particles risk damaging the injectors. At $250 apiece, this makes me nervous.
My friend, Bruce, came to the rescue! He recommended pouring fuel through some paper towels as a filter. So I rigged up my paint sprayer stand with a paint filter lined with paper towels. And I built a little rack to keep the fuel filter from escaping.
The pour went well. Fuel filtered slowly through the paper towels, but I waited patiently. (Yes…I did…I know that’s rare…but I did!)
The !@#$!@#$ Filter Wrench!
I grabbed the filter in both hands, walked it back to the bus, and carefully lifted it up under the frame and into the housing. Threading it on hand-tight, I reached for my filter wrench only to find that, since this filter was a bit longer, the wrench wouldn’t fit on past the power steering hose.
I believe my exact words were “AYFKM?!” These kinds of snafus happen to me all the time. Clearly I need to sacrifice more goats.
Anyway, I muckled ahold of it with a Vulcan death grip and cranked it as tight as possible. If it leaked I would have resorted to a cam strap or an old fan belt that I could have wrapped around it and cranked.
Bleeding the Fuel System on the DT466E
With the filer on I set about to bleed air out of the system. I cranked up and down on the Bosch primer pump then used a screwdriver point to push in the end of the bleeder valve. Some air fizzled out and a bit of fuel, so I kept pumping.
And pumping.
And more pumping.
Fuel shot out of the bleeder valve when I first opened it, then more air. So I kept repeating: close the valve, pump, open the valve, watch fuel spurt out, then air. Repeat.
Pump fatigue set in. (I hate it when that happens) So I decided to crank the motor over a bit to see if I could move fuel through the system.
I cranked for about 30 seconds, (The bus didn’t start or even sputter.) So I went back to the pump / bleeder valve technique for another couple of minutes, got tired, and repeated the engine crank.
By this time I could hear the battery start to drain.
I only have one.
466 diesels should really have 2 batteries in order to generate the compression needed for ignition. However, the bus has started so reliably that I hadn’t made this second battery a priority. (I have two, now!)
So I pulled the “house” battery that we use to run lights and the water pump from inside the bus. It’s a deep cycle marine battery, so I hooked it up with the other battery.
I sat in the driver’s seat.
I turned the key one click and waited for the cycling clicky things that happen.
That’s a sophisticated mechanical term…cycling clicky things…look it up.
I turned the key another click.
The bus cranked over and started up without even a hiccup!
Great happiness! (That’s a quote from Macbeth…look it up!)
Closing Thoughts on Replacing a Fuel Filter on a Skoolie DT466
Pre Filling the skoolie fuel filter HAD to have helped. But I highly recommend filtering the fuel first! If dirt particles damage injectors, that’s an expensive mistake. They run over $200 each!
I was able to bleed air out of that valve. I’m not sure if my primer pump works particularly well, however. It seemed I pumped forever and a day and never really built pressure. In some videos, people said that pressure would build to the point where you could barely pump. I didn’t get a lot of pressure..just tired.
A combination of pumping, bleeding, and cranking the engine, (with two batteries), however, did the trick.
I also wrote the mileage and date on the new filter so I’ll know when to change it again. I can’t even remember what I had for breakfast much less when I wrestled with fuel filter wrenches!
So replace that filter…if it needs it!
And good luck!