Botched a Simple Fuel Filter Change

[George DuBose]

While we are on the subject of bleeding, I became so frustrated trying to use the lever on the engine fuel pump that I installed a squeeze bulb in the fuel line between the primary filter and the fuel tank.

While this makes it very simple to pump the fuel up to the last bleed screw, I am wondering if the squeeze bulb is going to get along with diesel fuel.

Any thoughts?

George

[waterman46]

Originally Posted by OloteleMtn

Hire a mechanic to show you how to do it properly....best thing i can say.....good luck.

It’s not that complicated. You need to learn this.

First close the thruhull to the water pump">raw water pump.

Clean the Racor again if needed, Get gallon or so of clean diesel in a little tank from the gas station, fill the Racor and close it tight (what you should have done in the first place).
If you cranked the engine while Racor was empty, you will probably need to bleed the line and the primary filter. Loosen the top bleed screw on the primary filter housing. Put rag around that ares. Have someone push the starter button or keyswitch to crank the engine. It will not spray diesel as pressure in filter is low, but you need to observe the output of fuel at the bleed screw.
You may get bubbles but when you get only liquid fuel, tighten screw and engine will start. When engine starts, immediately open the thru hull to raw water.

[Boatyarddog]

Originally Posted by Chotu

Standard Racor fuel/water separator with 30 micron filter. It’s the primary filter. Like on all marine diesels.

Pic attached. There are 3 of these. One for the generator, two for the main engine and a whole lot of plumbing and valves that are actually very hard to see.

I guess the questions are:
1) can you leave air at the top of the Racor?

2) How can I bleed this system without getting diesel all over the place? It’s got to be several cups/pints/a liter of fuel in the lines and secondary filters to pump through before I get fuel with no air.

Two thoughts come to mind.
1 A small container, to temporarily place under the Racor and a bilge pad.
2 I have this model, I suck out the old diesel with a vacuum fluid extractor, place the spent filter in a container to dispose of, replace the filter cartridge, o-ring on the lid, and o-ring on the handle.
Then use a small plastic bottle filled with diesel to fill the Filter housing to the top.
Place the lid on and t handle, never any issues with air, clean up.
SV Cloud Duster

[Cadence]

Sounds like an air lock. Crack a fitting on the output side.

[OloteleMtn]

As can be seen from the numerous responses, there are some steps to follow....it seemed to me that the OP (no offense intended) was going to have some trouble following steps to resolve the issue...therefore my first response was to advise hiring a mechanic to correct the problems and show the OP how to do it correctly. Not understanding that OP was underway, or at least not on the dock, that my initial advice was not helpful; it was not meant to be that way......glad that after some guidance and food, things made more sense, but putting junk back into fuel system after removing it didn't seem like Chotu was tracking well.... I had a thought at first that maybe he was trolling us a bit. Troubleshooting takes a methodical mindset.

[Chotu]

Originally Posted by OloteleMtn

As can be seen from the numerous responses, there are some steps to follow....it seemed to me that the OP (no offense intended) was going to have some trouble following steps to resolve the issue...therefore my first response was to advise hiring a mechanic to correct the problems and show the OP how to do it correctly. Not understanding that OP was underway, or at least not on the dock, that my initial advice was not helpful; it was not meant to be that way......glad that after some guidance and food, things made more sense, but putting junk back into fuel system after removing it didn't seem like Chotu was tracking well.... I had a thought at first that maybe he was trolling us a bit. Troubleshooting takes a methodical mindset.

Don’t worry about it at all. No offense taken. You didn’t know I’m away cruising, had already done this a million times but more than a decade ago, or that I wasn’t a complete idiot. Ha ha ha.

I sure sounded like an idiot. The biggest problem was not eating. My brain shut down. I got foggy. Unable to think or remember what used to do.

Went provisioning and to puck up an outboard thermostat today so I’ll be getting to this tomorrow.

Really has shown me that sometimes the human factor can be the biggest failure mode. Probably goes for running the boat as well.

[GeneM]

When I change RACORs, I clean out the gunk and remove the filter. I replace with a new filter (use 10 micron these days). This leaves air in the top, so I add new fuel from a gallon jug I keep full. I suppose there is a little air in the top, but I assume it stays on top.

[kryg]

I have the same filter housing, to overcome this problem (I DON'T HAVE AN Electric Pump). I fitted a gas squeeze bulb like one has on your outboard motor fuel hose, mine is installed after all the off and on fuel valves, it as part of the fuel hose installed, just before the fuel feeds into filter housing. I found it is a fail proof solution, especially if your electric fuel pump fails which mine did years ago I never replaced it. Also if there is air in the system, by squeezing the bulb I bleed the air out of the system. it is simple inexpensive and it has never failed me in 7 years. Hope this helps.

Originally Posted by Chotu

Ok, there is nothing simple about the fuel system but I was trying to do a simple Racor prefilter change.

I haven’t done this in at least 10 years. I have Outboard’s on my catamaran.

Here’s what I did.


1) Figure out which of 3 Racor units goes to the engine and is currently in use filtering. Surprise surprise it was the very dirty one.

2) Drain scum out of bowl and filter housing. I drained to completely empty because there is an electric fuel pump. Figured I’d refill with that.

3) change filter and close up Racor with new seals,etc. left it dry

4) figured I’d bleed Racor air from the secondary filters on the engine using the manual bleed pump. . Nope. They spurt out tons of diesel instead of filling Racor.

5) used the electric pump to try to fill the Racor. Literally nothing. Just makes noise and does not fill Racor.

6) dumped the scum back into the Racor I drained out to at least get things working. Nope. Not enough to fill the Racor to the top. About 1/2” or 1cm of airspace at the top of the Racor.

My concern at this point is I’ve screwed up bad

How do I get the air out? I don’t want to just run the engine and bleed. It’ll spray diesel everywhere. We have to live in here and my lungs can’t handle that level of irritant.

I don’t remember having all this trouble on my old yanmars. But they didn’t have a fuel polishing system and I didn’t drain out the Racor completely I don’t think.


I’m VERY rusty. What do I do next?

[Jim Cate]

Originally Posted by George DuBose

While we are on the subject of bleeding, I became so frustrated trying to use the lever on the engine fuel pump that I installed a squeeze bulb in the fuel line between the primary filter and the fuel tank.

While this makes it very simple to pump the fuel up to the last bleed screw, I am wondering if the squeeze bulb is going to get along with diesel fuel.

Any thoughts?

George

There was recently a thread on this very subject. The responses, as usual, ranged from OMG, ya gonna die to reasoned stories from folks who had been using such a bulb for years without issues (I'm one of those).

If you are a glutton for punishment, a quick search will reveal the thread in all its gory glory, and you can make your own interpretation of the evidence.

Jim

[Wotname]

Originally Posted by George DuBose

While we are on the subject of bleeding, I became so frustrated trying to use the lever on the engine fuel pump that I installed a squeeze bulb in the fuel line between the primary filter and the fuel tank.

While this makes it very simple to pump the fuel up to the last bleed screw, I am wondering if the squeeze bulb is going to get along with diesel fuel.

Any thoughts?

George

Originally Posted by Jim Cate

There was recently a thread on this very subject. The responses, as usual, ranged from OMG, ya gonna die to reasoned stories from folks who had been using such a bulb for years without issues (I'm one of those).

If you are a glutton for punishment, a quick search will reveal the thread in all its gory glory, and you can make your own interpretation of the evidence.

Jim

Here you go George. Read and weep

https://www.cruisersforum.com/forums...it-233630.html

[Chotu]

Originally Posted by Wotname

Here you go George. Read and weep

https://www.cruisersforum.com/forums...it-233630.html

Since getting my ability to think back, my plan today is to just stick a fuel pump bulb into the line TEMPORARILY before the Racor. Between the Racor and fuel tank.

Then, I can squeeze the air up and out.

Once the Racor fills all the way with the cap off, I’ll cap it and work any air I may have introduced out through the bleed on the secondary filters.

[NYSail]

First thing I always do is shut the fuel supply so hose stays primed. Then I open bottom of filter and drain out any sediment. If the bowl is bitty I will clean it out..... then I Change all gaskets and put new filter in then fill with fuel right to the top.... screw lid on, open fuel supply then start engine.

Good luck
Greg

[Chotu]

All done! Still not 100% sure about the aftermarket and unlabeled plumbing in the pre-engine fuel lines. 3 Racors and 3(qty) three way valves.

Hoping to find some notes in the ship’s papers.

[kryg]

Simplest is best, that is what I did, 7 years ago to replace the electric pump and bleed the system. Still works.

Originally Posted by George DuBose

While we are on the subject of bleeding, I became so frustrated trying to use the lever on the engine fuel pump that I installed a squeeze bulb in the fuel line between the primary filter and the fuel tank.

While this makes it very simple to pump the fuel up to the last bleed screw, I am wondering if the squeeze bulb is going to get along with diesel fuel.

Any thoughts?

George

[waterman46]

Originally Posted by Chotu

All done! Still not 100% sure about the aftermarket and unlabeled plumbing in the pre-engine fuel lines. 3 Racors and 3(qty) three way valves.

Hoping to find some notes in the ship’s papers.

Those 3 way valves are probably to let the fuel flow be selected to your genset and/or main engine, and maybe to pull from one or two fuel tanks. Of course I don't know the configuration of those in your case.
On my boat we now have two fuel tanks and one of them has two pickup tubes, and we have engine and generator. And an electric fuel pump near the main tank next to the valve farm. The electric pump can be switched into the flow or isolated from it, and is sometimes required to start the flow when switching to the second tank, as it is a wing tank a long way from the valves. Total now about 5 3-way valves and maybe another 5 shutoff valves. You can bet I made my own diagram, because within a couple months after figuring it all out, I forgot it all.