Suzuki DF140 - stuttering - black foam in fuel tank

[ryanbsc]

Hey Guys

I am new to the forum - I wish I knew this forum existed a long time ago.

I have two suzuki DF140 bought them 9 months ago new.
When the engines were installed I had the fuel tank flushed ( Aluminum fuel tank) and all fuel lines/hoses replaced.

As of 3 weeks ago the port engine would shudder above 3,500 RPM and then anything above the RPM would flucuate , ie it would go to 5,000 RPM then after 20 seconds it would drop to 4,500 rpm for 10 secs then jump back to 5,000 rpm and so on.

I had to sent to the dealer - who is rubbish, and not properly qualified.

They stated that there are black particles found in the fuel tank, and the fuel lines need replaced, + tank flushed. This has damaged the fuel regulator valves.

However I do not understand how there seems to be what looks like " black foam / sponge" all of a sudden in the fuel tank and how the fuel filters didnt stop this.


Can you guys tell me if this seems right, or could the black foam come from i.e a blank stopper cap somewhere in the engine , and is coming in to the tank from the return fuel line?.

Kind Regards

Ryan

[Solarman]

df140's, fuel line issues

What your pics look like, is a fuel line that breaks down from ethanol gas use. It could be the fill hose to the tank, the vent/ overfill hose, or any fuel line that is old and hasn't been replaced. Ethanol tends to break-down the rubber on the inside of the hose, it becomes a black sooty substance. If you squeeze the fuel lines you can feel soft spots throughout its length, And, it will block filters, and screw up running motors.
It doesn't sound like all the old fuel lines were replaced in the first place.
Only solution, replace all old lines from tank to motor, clean or replace all fuel filters. Stop using ethanol fuel. Find a station that sells marine fuel (no ethanol).
Good luck.

[Harper]

Solarman's right. It definitely looks like deteriorated fuel or vent line. You can buy some fuel lines that are supposedly ethanol-resistant, but if you can find it over there, non-ethanol gas is the best way to go.

[Solarman]

Thnx Harper, never thought of his area... But, UAE, would not have thought they would use ethanol fuel over there. Don't they have ample fuel supplies?
Also, if non-ethanol (marine fuel) isn't available, I believe they have some additives that might help some with ethanol based fuels, but not sure in Dubai?

[ryanbsc]

Thanks

Hey guys

Sorry I didn't reply, for some reason I never got the notification emails to say that I had a reply, really sorry.

Hmm that's good to know, I believe that the vent hoses were not replaced, I will have them replaced.

Once all this is done

And I replace water separators - should I have the fuel filters on the engine replaced?

If so what fuel filters should I have replaced?

regards

Ryan

[ryanbsc]

ethanol fuel

Hi Guys

Forgot to mention that UAE does not use ethanol fuel here

Just standard 95 Oct rating fuel, however will have the lines replaced

The dealer in UAE is absolutely rubbish, so if someone could suggest all the exact filters to change, then I will request them to do so.


Can you advise if once filters changed, the engine should be protected from the filters? ie no damage to the actual engine?

Regards

Ryan

[Harper]

If you have a large spin-on canister type filter(s) in the fuel line prior to the engines, then definitely change that, and also your low pressure filters, 15410-87J30. Hopefully, you won't have to go as far as the high pressure filter and cleaning of the VST. But we'll cover that if you problem is not solved. Also, I think there's an anti siphon valve on the tank outlet that has give some a problem, and they've replaced that with a regular barbed hose fitting.

Concerning email notifications of thread postings, I don't think it works. All I ever get is a notification of PMs.

[Solarman]

new df140's, fuel line problems

Ryan, your motors are less than a year old. Do you have multiple (2 or more) tanks on the boat? How olds is the boat? Where did they get the black particles from, fuel/water separator, if so, the regulator (and fuel system on the port motor) may be fine? The deterioration of fuel lines is more common with ethanol fuel usage. If the black particles came from the vst (vapor separator tank), then it could be in the high pressure filter. Also, you haven't mentioned the starboard motor for problems. This makes me think you have multiple tanks, and that maybe those port fuel lines were missed during replacement? Maybe a poor grade of fuel lines were installed? Something doesn't add up?
Good luck. Keep us posted.

[ryanbsc]

single tank

This is a good point and thank u for replying .
I have 1 fuel tank and two fuel lines going to two water seperators which goes too two engines . the port engine shows no issues while starbord does, and during sea trial by suzuki duae we change all watar seperators plus fuel filter and done anotjer sea trial to be met with same results , if not worse.

So now having tank cleaned and remaining fuel lines replaced


Any feedback immensley appreciated.

[ryanbsc]

boat

Sorry the boat is 2006

[Solarman]

new df140's, fuel problems

If the particles didn't make it past the small low pressure filter on the side of the motor you should be ok. Can tell with another test run.
If still running poorly, then the particles made it past the separator and the low pressure filter. This means probably the rest of the fuel system, including the low pressure pump(s), the vst, the high pressure filter, regulator, vapor ventilation lines, and maybe, fuel rail, and injectors will need to be cleaned too.
Can't imagine how they missed the starboard fuel line in the beginning? Hopefully, they have replaced all the remaining old lines now.
Good luck, keep us posted.

[ryanbsc]

Clean Tank

Thanks so much everyone so far for all your contributions , it has been so reassuring to talk to people who actually know what they are talking about.

The fuel tank has now been cleaned, and all fuel lines inspected, and they confirmed that all fuel lines including vent lines were all replaced last year.


There was like a foam gasket that is for the top hatch of the aluminium fuel tank that was crumbling so they think that the debris was from that, or dirt from a fuel pump as apparently it happens here at marine fuel pumps.

I spoke with Suzuki

They said before filling the fuel system with fuel again I will change

- Water seperator
- Low pressure fuel filter
- High Pressure fuel filter

They have already cleaned out the VSP apparently .

I have questioned several times why is the starboard engine running perfectly when all this debris was found.

They also said particles was found in the VSP.

The arguement next if the engine still doesnt run right on who pays for any damage. As in theory Suzki should spec the engines with a fuel filter good enough to catch this sort of thing.

I get the boat on Saturday and will do another sea trial, then will update you.
*fingers crossed its all ok* these engines are feb 2014 with 50 hours, not wanting to spend a fortune on a new engine repair.
Kind Regards

Ryan

[Solarman]

df140, fuel issues.

Thnx Ryan for the update, good luck.

[ryanbsc]

Fixed

Hey Guys,


Sorry it took a while to update you all,

We went for the sea trial and then the other engine was behaving the same as the previous engine, therefore same repair, cleaned entire fuel system , replaced fuel regulator + valve and now runs sweet.

Also upgraded water seperators to the drainable Suzuki type.

Bit disappointing that the fuel filters don't pick up the crud before affecting the fuel regulators, luckily everything was fixed under warrenty.


Thank you again everyone for all your help and suggestions .

Kind Regards,
Ryan

[Solarman]

fuel problems

Thnx Ryan. Posting your update to the problem helps us all, thnx again. Happy boating.