Clogged Fuel Filter and no replacement - any tricks for the case of cases?

DangerousPirate

DangerousPirate

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Just asking this regarding a beery conversation yesterday. If you have an issue with your fuel filter (it's clogging up, dirty fuel/diesel bug) and you change your spare at sea you usually should be fine until you're back in port, where you can get a new one. But what if the second filter clogs up, too? Maybe because it's a rather long trip or seas get a little rough. Or maybe you didn't even have a spare. Doesn't matter why, it's just hypothetical.

Can you actually rip the old paper from the filter casing and replace it with a cut up tshirt or some socks just to make it back to the port? Is that a valid trick? How many microns is that roughly? :D
What else could you do hypothetically?
 
I can talk from own experience ... yacht and truck.

Both did the same.

We ended up with engine only running for very short stints based on the slow fill up of fuel via the clogged filter. Basically engine would stop ... fuel would slowly pass through enough to start and run till filters flow was too little to sustain engine. Wait and start again.

The run time got shorter each time ...

Eventually the Perkins boat engine Injector pump clogged ... inside the fuel IN connection is a small thimble filter that is extremely difficult to get at. As I was told by diesel mechanic - its not designed to be got at !! Its basically the pumps protection ! Anyway - it clogged and then we were only sail. After getting 'home' - pump was removed and given to local Volvo Truck service who recon'd the pump etc.

The Mercedes Truck did keep restarting and we got home ... next day complete clean up and new filters.

The above is to illustrate my personal opinion - if all filters are clogged ... then do not try anything else .... it could lead to similar as I had ... a complete de-clogging of the injection pump ...
It was that bad - I actually purchased another second hand pump as stdby just in case.
 
I have three diesel filters, a primary, a secondary and one on the return to the tank.

I keep eight of the Racor 500 type in stock on the boat and two of the Yanmar secondary.

Not cheap but I am always prepared.

I also keep a pump that will enter my 900 litre tank through the fuel gauge hole and empty it - provided I can find something to pump it into! Had do use it too!

Like the Scouts moto, Be Prepared.
 
My current boat came with a lot of gunge and rust from steel jerry cans in the bottom of the built in fuel tank. We carried a box of spare filters and got a lot of practice berthing under sail after getting mildly shaken up offshore.

Eventually, resolved the problem by replacing the original CAV filters with spin on ones for easy changes and then plucking up courage to clean out the bottom of the fuel tank as no matter how many filters I changed there was still more muck to block the new ones.

So to answer the OP, the trick is to have sails and practice boat handling in confined spaces without the engine.
 
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Racor - brilliant! Just use the crew's toothbrush to clear the gunge!! In (about)1999 we had an issue with a new-to-us boat. The engine stopped and we were being sucked backwards by the tide into the Corryvreckan. The filter element was pulled and cleaned, I noticed it had a 1970's date and had imploded with the pump suction. It took us 40 mins to get back to where we were originally. You can't do that with spin-ons, so more than one spare is good sense, and wiping with grease then wrapping in clingfilm before storing aboard helps too. Attempting a "fix" with spin-ons to get you home may cost you an injector or pump - and you can't fiddle them to continue the journey hypothetically of course!
 
Billjratt said:
Racor - brilliant! Just use the crew's toothbrush to clear the gunge!! In (about)1999 we had an issue with a new-to-us boat. The engine stopped and we were being sucked backwards by the tide into the Corryvreckan. The filter element was pulled and cleaned, I noticed it had a 1970's date and had imploded with the pump suction. It took us 40 mins to get back to where we were originally. You can't do that with spin-ons, so more than one spare is good sense, and wiping with grease then wrapping in clingfilm before storing aboard helps too. Attempting a "fix" with spin-ons to get you home may cost you an injector or pump - and you can't fiddle them to continue the journey hypothetically of course!
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My Perkins fuel system has two high performance filters in series. The pre-filter is the one that would block with debris. The filters are interchangeable in an emergency.
The pre-filter has a water sensor and alarm on the engine control panel.
On a previous less sophisticated set up we had blocked fuel lines due to diesel bug. I used a 20 litre fuel can of fresh fuel as a tank and just ran on the primary filter to get us home. You could filter fuel out of the main tank if you only had an empty fuel can by filtering it through a coffee filter, assuming you had a pump to suck it from the main tank.
It's amazing what you can bodge together when you need to. I wouldn't bother cleaning a blocked filter.
 
I’ve seen a system where there is the main tank, then fuel is filtered up to a smallish day holding tank.

From there the cleaned fuel then has another filter inline before going to injectors.

Felt like quite a sensible idea to me, especially if the day tank could feed the engine by gravity to make bleeding the lines easier.
 
Best setup I,ve seen is two primary Racors - in parallel - with a change over valve, , so that you can change over at the first sign of a problem and stay under way while you clean or fit a new filter on the problem side, or even leave it until circumstances permit
 
lusitano said:
Best setup I,ve seen is two primary Racors - in parallel - with a change over valve, , so that you can change over at the first sign of a problem and stay under way while you clean or fit a new filter on the problem side, or even leave it until circumstances permit
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At a cost. Its a very expensive system where half your installation is redundant 99.9% of the time.
Our Perkins system uses Donaldson 1/4 turn collar locks on the fuel filters. It's a commercial system but makes for super fast filter changes. The engine has an electric fuel pump so bleeding is something we don't need to do. It's automatic
 
lusitano said:
Best setup I,ve seen is two primary Racors - in parallel - with a change over valve, , so that you can change over at the first sign of a problem and stay under way while you clean or fit a new filter on the problem side, or even leave it until circumstances permit
Click to expand...
I did this on Jissel after a rather traumatic F6-7 entry into Portsmouth Harbour under sail, but got a pair of filter holders from a car breaker - a LOT cheaper than Racor, but possible not much cheaper than Chinese knockoffs.

It more than paid for itself because the ability to switch filters in seconds meant I didn't feel the need to do an annual filter change, so a pair of filters lasted 10 years or so until they got rusty enough to be a concern.
 
if you look at the top of some racor elements they have a deliberately moulded weak spot in the plastic that you can knock out to by pass the pleats.
 
De.windhoos said:
From experience; you can wash a filter in clean diesel if it’s not too badly clogged up. Talking about a regular CAV filter.
Click to expand...

Not something I would do without serious thought first.

I did this once ... and regretted it. The Filter failed to unclog enough ... what did come free now infected the 'exit' side of the filter and passed into the upstream fuel lines.
 
Stemar said:
I did this on Jissel after a rather traumatic F6-7 entry into Portsmouth Harbour under sail, but got a pair of filter holders from a car breaker - a LOT cheaper than Racor, but possible not much cheaper than Chinese knockoffs.

It more than paid for itself because the ability to switch filters in seconds meant I didn't feel the need to do an annual filter change, so a pair of filters lasted 10 years or so until they got rusty enough to be a concern.
Click to expand...

I have considered fitting a dual system ... but actually one that places a filter nearer tank ... to do primary filtering - then passes on to the usual engine fuel filter. That way - I can have a 'quick-release' filter doing most of the work and original engine side filter having a 'holiday' .....

If I did it - I was also going to add a pump to do the priming.
 
DangerousPirate said:
I have 3 spares on my boat, but the discussion was about engineering a temporary solution to replace a fuel filter.
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There is not a good way to do this.

My injector pump and injectors are away at the diesel specialists now.

When I bought the current boat it has badly bugged and water contaminated fuel. No spare filters on board and a piece of pipe with jubilee clips and a spigot that was just long enough to bypass the two filters, the Racor primary and the Yanmar secondary by connecting directly to the tank feed and the injector pump.

I strongly suspect that the first owner had blocked filters in the Bristol Channel, had used all his spares and bypassed the filters with the pipe.

For the last five years I have been struggling with a hot starting problem. The diesel specialist has found wear in the pressure and distribution end of the injector pump and one bad injector nozzle. They believe dirty unfiltered fuel was the culprit. The pump is struggling to provide enough pressure to pop the injectors while cranking with warm fuel.

Cost estimated at £1300-£1700.

So, IMHO, not a good idea except in a dire emergency.
 
geem said:
I used a 20 litre fuel can of fresh fuel as a tank and just ran on the primary filter to get us home.
It's amazing what you can bodge together when you need to. I wouldn't bother cleaning a blocked filter.
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I've done exactly that.
Clogged fuel line sailing down from Wick to Inverness. Very little wind and wanted to get into Inverness Marina, which means navigating under the Kessock Bridge, and into the River Ness.
I managed to sail in past Chanory Point, and anchor, then rummaged in the spares box, and found enough fuel line to connect a 20L can of diesel direct to the primary on the Yanmar.
The only problem with that is that the return line was still connected to the main tank, so not all the 20L is available for propulsion.
But it got me home, after waiting for slack water under the bridge.
 
DangerousPirate said:
Just asking this regarding a beery conversation yesterday. If you have an issue with your fuel filter (it's clogging up, dirty fuel/diesel bug) and you change your spare at sea you usually should be fine until you're back in port, where you can get a new one. But what if the second filter clogs up, too? Maybe because it's a rather long trip or seas get a little rough. Or maybe you didn't even have a spare. Doesn't matter why, it's just hypothetical.

Can you actually rip the old paper from the filter casing and replace it with a cut up tshirt or some socks just to make it back to the port? Is that a valid trick? How many microns is that roughly? :D
What else could you do hypothetically?
Click to expand...
you can clean a clogged up filter by rinsing it in PETROL (2 stroke mixed petrol will work just as well as clean petrol). This will clean the filter and you can reuse. eventually the petrol will degrade the rubber seal on the filter but it should do a week or so of cleaning like this to get you somewhere you can get new filter.
 
So, regarding the entire discussion about dual filter systems etc, I found this thing via google: Decontaminator / Water Separator Model FGD100 suitable for engines up to 150 bhp
There is a really nice video on the frontpage explaining it, and I read some threads here in the forum about it. The only thing is, they don't seem to be selling it any more. Not sure what happened. But this sounds like a really nice system.
 
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