Gasoline in the Diesel Tank?

[Alan Wheeler]

The engine doesn't run erratic. It sounds like 100 angry guys trying to smash the engine with sledge hammers :-0

[svHyLyte]

Well--40+ gallons (US) of diesel fuel are now sitting in 5-Gal buckets at the fuel dock waiting for the recycler. No gasoline smell, no "stratification" with the sample taken thus far; and, the only thing that would have ignited the fuel sample we put in a #10 pickle-jar lid would have been a blow-torch (as far as we can tell)!

Stephan hand-pumped 35+ gallons back out of the fuel filler valve and the remaining 5 or so from the feed line between his Racor and the secondary fuel filter on his Perkins 4-108. Both filters were subsequently changed, 10 gallons of fresh (RED!) diesel pumped into the tank, the fuel lines purged and bled; and he's back in business. Frankly, I'd have been PO'd but his viewpoint is that his tank has been cleaned out and the fuel dock paid for all of the fuel so, other than having to do the job in 103 deg (F) weather (Florida in the summer), he's ahead. (Of course, someone else may be on the hook but the fuel dock is doing everything possible to contact other owners that fuel-up last weekend.)

The lesson for me from this--even after 40+ years of sailing--is the reminder that there are no routine tasks aboard a yacht. EVERYTHING requires vigilence.

Regards,

s/v HyLyte

[svHyLyte]

A short follow up--

In the last two weeks our Pal has suffered the loss of both his lift pump and injection pump--failed seals-on a Perkins 4-108 with less than 2,500 hours. Another acquaintence who happen's to be an expert mechanic commented that had gasoline gotten to the seals of either units, they would fail in short order, and so they have.

As it seems no one in the Tampa Bay area (west Florida, USA) had even the least interest in extracting the injection Pump, Steven was left to do it himself, which took upwards of 8 hours. A rebuild will be in the range of $500.00, followed by may hours to reinstall the unit. The lift pump is relatively "cheap" at $49.00 (US).

There but for the grace...

Strict attention to fueling is an absolute necessity!

Regards,

s/v HyLyte

[hellosailor]

Curious that "enough" gasoline would have gotten into the injection pump to ruin its seals--but NOT gone the foot past that into the engine?? And you weren't able to confirm gasoline contaimination in the tank at all?

Or is this another boat we're talking about?

[Alan Wheeler]

Hmmm, it's not low sulfer Diesel is it?? This can cause the seals to leak. It may not have been gasoline that was the culprit. The difference is, Gasoline would probably swell up seals and gaskets etc, low sulfer fuel dries them out and the shrink and become brittle and crack. It is the process of removing the sulfer that alos removes some of the Aromatics that help seals stay healthy.

[svHyLyte]

We still do not know whether gasoline was pumped into Steve's tank or not. All of the indications after draining and flushing his system are that it was not, but... The failure of his lift pump and injection pump seals so soon after the fact does seem odd, particularly as others more knowledgable than I warned of these type failures if gasoline got to them. Yet, to do so, the engine would have had to have run without diffficulty with gasiline in the fuel which seems very unlikely, so...

Steve's boat and ours are nearly identical. In fact they are only 15 hull numbers apart--his was coming off the line when ours was starting. We have the same engines, exactly, but ours has over 3300 hours while his, because the previous owner always laid the boat up during winters, has only 2500. And, for the last 5 years we have used fuel from the same source. Yet he's experienced this failure while we've not had any problems (thus far).

The only thing out of the ordinary after draining the suspect fuel load from his boat was his addition of a product known as "StarTron" to the replacement fuel. Whether that might have contributed to the situation, who knows?

Curious, no?

s/v HyLyte

[jscott]

The loud knocking noise is indicative of a low Cetane value of the fuel, diesel has a high cetnae value gasoline a low cetane value. This would be a direct indication of fuel contaminated with gasoline.

The Startron (don't know what it is) may have been a Cetane improver.

Gasoline has a high aromatic content (good octane value), diesel a low aromatic content (low cetane value).

Aromatics are very good solvents and can permeate into elastomers, cause swelling and eventual failure.

Dumb question when the fuel supplier called him why didn't he just go back and get them to change out the fuel? Wasn't it their fault?

The specific gravity of diesel is quite close to gasoline so density would not be a good way to tell the contamination.

Diesel and gasoline are complety misicible, any amount.

It would seem that odor can be misleading as well.

The flash point of diesel should be greater than 150 F, that means that if you hold a small flame over a 5 cc sample of the diesel has it is heated will not ignite until the sample reaches 150 F. Easy test in a lab but pretty hard to measure acurrately, in a kitchen.

Best I can think of is an aromatic test strip, like PH paper but in a tube (GasTech).

Test a known good sample and compare to unknown sample.

I would suggest no more than 5% gasoline in diesel.

[encore]

An interesting thread. I had a diesel Rabbit VW that got a little less than 8 gallons of gas loaded into the tank by a station attendant. I drove it for about 45 minutes to a dealership and they drained the system completely. (I didn't know they had put in the gas). It did definitely smell like gas and it was running more and more erratically as I progressed. Didn't seem to hurt the engine any as I drove it for an additional 290,000 miles after the incident.
Ellis

[SkiprJohn]

Had the same thing happen to me with a service station attendant. I only got half a load of gas and then after I caught the error had him put in the other half with diesel. The Nissan pickup ran fine for another 50,000 miles until the body rusted away and I sold it. I still see it on the road after 3 years. I don't know how he keeps it patched up enough for it to stay running. So I don't think I would worry about a 50/50 mix but I would with a higher percentage of gasoline.
JohnL

[jscott]

Originally Posted by SkiprJohn

Had the same thing happen to me with a service station attendant. I only got half a load of gas and then after I caught the error had him put in the other half with diesel. The Nissan pickup ran fine for another 50,000 miles until the body rusted away and I sold it. I still see it on the road after 3 years. I don't know how he keeps it patched up enough for it to stay running. So I don't think I would worry about a 50/50 mix but I would with a higher percentage of gasoline.
JohnL

As we have seen the damage was cause by elastomer failure. In your case, that did not happen, this is likely due to different type of elastomer in your seals. Good on Nissan.

While the cost of elastomers that will endure gasoline, diesel, and for that matter, methanol, and ethanol is quite a bit higher the actual cost of the seals, is quite small in the overall picture.

I for one would like the major manufactures to put in the better seals, that would prevent the failure above, and also allow most cars with electornic fuel injection, to run gasoline, methanol, ethanol, in any mixture.

The knocking caused by the gasoline detonating in the cylinder, may cause some damage, overheating to the piston, or con rods, this should normally be controlled by ensuring a light load on the engine, I would guess that if the engine continued to run, on whatever mixture of diesel and gasoline was present in the engine, if the seals hold, then the damage would be minimal, at light loads.

Of course if your just going to idle the engine, to get rid of the mess then you might as well pump it out and slowly mix it back in with good stuff.

I would not exceed 5% bad stuff to good stuff, for trouble free motoring.

[svHyLyte]

As I started this thread some while ago I thought a follow up would be in order.

Our pal Steve's engine is now running quite well after further repairs, seal replacements and the replacement of his lift pump. But--his luck does not seem to be holding.

This past week during a terrible storm, his mast-head was hit by lightening! The strike apparently vaporized his radio antenna; all of the glass on his mast-head lights melted and fused together; and, of course, all of his newly installed Ray Marine Instruments, Radio, Radar, et al were toasted! Even his compasses were goofed up by the EMP!

But--His engine works!

s/v HyLyte

[Strygaldwir]

I always pump fuel into my tanks via a West Marine "Baja" type filter. It lets me see if there is any issue with the fuel while I am pumping it. Even when I fill from my jugs, I alway use the filter. I guess peace of mind is one of the additional benefits of this regime.

[Celestialsailor]

I'm surprised no one had mentioned to take a small sample of the suspected fouled up fuel to a safe place and see if a match will ignite it. Remember...I said a safe place.

[dacust]

Originally Posted by Celestialsailor

I'm surprised no one had mentioned to take a small sample of the suspected fouled up fuel to a safe place and see if a match will ignite it. Remember...I said a safe place.

See posts #4,8,11. You must have just scanned this page. All mention was on the first page of posts.