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Could it be the sand???

J

JJDebeers

Regular Contributor
A few weeks ago my stbd engine died when I tried running it over 2500 rpm after a few minutes. A few pumps of the throttle revealed a dry fuel bowl (no squirts from accelerator pump).

I'd remove the water separator, pour some gas down the carb throat, and she would start right back up. I limped back to the slip at lower engine speeds.

I thought maybe a fluke air bubble in the fuel line from sitting all winter? So on my second trip out the same exact thing happened, and I got it started again the same exact way.

My first thought was something wrong with the carb. Junk, gunk, a stuck float, etc. was not allowing the bowl to replenish at higher engine speeds, but low engine speeds were ok. The Carter carb on that engine was not in great shape, so I installed a newer, freshly rebuild Carter AFB.

When I did the carb, I also replaced the inline fuel filters and water separators as a precaution. I poured the contents of the old water separator into a bucket and to my suprise a small handful of sand, or some type of gritty particulate, came out.

Could this sand in the water separator have been the culprit all along? Blocking fuel flow at high engine speeds, but passed enough fuel at low speed?

Anyone else experience problems from a dirty or blocked separator?

Thanks,
JJ
 
If the sand is/was the culprit, it's more likely that it was clogging up your fuel filter than the water separator. The separator is a relatively free-flowing device and, while it will filter our some sediment (as you've seen), it's mainly capturing the water via gravity. If some sand was making it through the separator, it would/could, however be enough to block the small screens of the fuel filter.

A water separator is more likely to give you problems when it's become completely filled with water.........because that water will eventually "overflow" back into the lines.
 
Hate to say it, but your problems aren't over. Be sure to have several filters aboard, and dump the water separator regularly.

Jeff
 
I bought the boat last September and it sat in dry storage for a year before that. After buying, I launched it and ran it about 70nm to where it is today.

No issues what so ever. Why the sand now?

-JJ
 
Are you familiar with the marina you're fueling at? Any idea where their tanks are located?

As Jeff suggested, it either snuck in there via some outside source or it came in with a fuel-up. Either way, you should really draw some samples out of your tank to get a feel for how much you have in there. There's only so much you can rely on the separator and fuel filter to catch that stuff. If it starts to sneak by the goalie, it's bad news.
 
The boat was laid up for about a year before I purchased. It had under 1/4 tank of about 2 year old gas. I purchased last September and launched it at a nearby public landing. Ran it over to DeMillo's Marina in Portland ME and topped off the tank. Very high end marina, with high end yacht clientel. Could have sand in their gas but I doubt it.

After the $800 fill up, the tears eventually stopped and I was underway. About 4 hours at 15 knots from Portland ME to Hampton NH. Not a hiccup along the way. I hauled the boat in October and laid it up for the winter. It was shrink wrapped and there was no sand-blasting near the boat.

It started and launched fine this spring. I've run into the above issues on my only 2 trips out.

Yesterday, I installed the second newly rebuilt Carter AFB on my port engine. I also replaced all of the copper fuel line with USCG hose from the water separators to the motors. From the water separators back to the fuel tank is still the original copper.


I also replaced the water separators and inline filters on both engines. I dumped the old port side separator to see if there was any sand. No sand, but a few "floaties" and other small particles. Like I said before, the stbd side separator actually had dense sand in it.

Since the port side separator was relatively clear, and that engine has been fine, I'm chalking up my fuel starvation to the sediment in the stbd side.


I should be taking it for a shake down run this weekend. I'll keep an eye on the water separators and post the results.


Thanks,

JJ
 
It doesn't sound like a carb issue, if you are getting debri from the water seperators it's most likely crap being sucked up from the bottom of your fuel tank. Ethanol fuel is a bitch on our old fuel tanks and are being eaten away from it. Do you know if they are original fuel tanks?
 
JJDebeers said:
It's definitely a fuel issue, so how can you NOT consider the carb?
Click to expand...

The sand problem is originating on the other end of the fuel system.....specifically, the tank (unless the fuel is flowing backwards). It's possible that a carb issue could also exist.....but I think you have to get the sand out of the system and go from there.
 
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bogdenz said:
The sand problem is originating on the other end of the fuel system.....specifically, the tank (unless the fuel is flowing backwards). It's possible that a carb issue could also exist.....but I think you have to get the sand out of the system and go from there.
Click to expand...

The port side engine is drawing fuel from the same tank with no issues. Could be the sand, or the sand could be a coincidence.

-JJ
 
kimcrwbr1 said:
You need to clean both sides if it needs it, it ia amazing how well the heat transfers between a liquid to liquid heat exchanger unlike air to liquid. heat allways transfers from hot to cold no exceptions even a thin film of corrosion will insulate the transfer that is why the tubes are thin wall less insulation between the two liquids. The inlet and outlet tubes are by design the hot side flows slower though the heat exchanger than the cold (raw water) to pull as much heat out of the coolant or oil as possible.
Click to expand...

Huh? Did i miss something?
 
kimcrwbr1 said:
You need to clean both sides if it needs it, it ia amazing how well the heat transfers between a liquid to liquid heat exchanger unlike air to liquid. heat allways transfers from hot to cold no exceptions even a thin film of corrosion will insulate the transfer that is why the tubes are thin wall less insulation between the two liquids. The inlet and outlet tubes are by design the hot side flows slower though the heat exchanger than the cold (raw water) to pull as much heat out of the coolant or oil as possible.
Click to expand...

I think you posted in the wrong thread.
 
If both motors are drawing from the same tank, thats another conundrum !? I think we need Ricardo with the great pictures and graphs and flow charts !!!!!! Ricardo, you out there?? :cool:
 
Trojanman said:
If both motors are drawing from the same tank, thats another conundrum !? I think we need Ricardo with the great pictures and graphs and flow charts !!!!!! Ricardo, you out there?? :cool:
Click to expand...

Conundrum? Do I have a 2nd gas tank that I didn't know about? It looked like 1 big 220 gallon tank to me. Where's the conundrum?

-JJ
 
JJDebeers said:
Conundrum? Do I have a 2nd gas tank that I didn't know about? It looked like 1 big 220 gallon tank to me. Where's the conundrum?

-JJ
Click to expand...

The conundrum being that if you have one tank then both water serperators and carbs should have sand. Having twin engines, I thought you had two fuel tanks (smart a$$). If you had sand in just the starboard side seperator, does fuel enter there first from the tank ? If it's crap in tank , it would get trapped in the first seperator it enters.
 
Do you have two fuel tanks? I'm new at this so I'm really just trying to learn as much as possible. Not trying to be a wise guy.

I have one fuel tank. Two lines coming off of the tank. Each line has it's own separator and in-line filter before the carb.

Why the sand went to the stbd side, I don't know. The port side had some floaties and light particles in it, but no dense sand.

Maybe during layup, the bow was slightly angled up and to the stdb side. This would allow any sediment in the tank to settle near the aft stbd corner. Upon startup, the stbd dip tube sucked some of it up.

-JJ
 
kimcrwbr1 said:
How would sand in any amount get into any fuel tank unless put there intentionally.
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Is this a serious question? The boat and fuel tank are 35 years old. The sediment that is in the tank, maybe not "sand" like on the beach, but some type of gritty sediment, can get in there a number of ways:

1. Through the tank vent
2. Through the fill tube
3. With the gas itself (it isn't perfectly filtered at the pump)


Over the course of 35 years, the stuff builds up in there. That's why we have fuel filters.


-JJ
 
Ethanol is famous for loosening up 'stuff' that was happy lying there for decades.

If you boat runs with a slight list (like mine) one engine will pull more crud out of the tank than the other.

Jeff
 
It sounds like you have replaced everything in the fuel system except the anti-syphon valve thats located on top of your fuel tank. If you take her out and she's still starvin' for fuel,you might want to take that off and clean or replace it.
 
fastjeff said:
Ethanol is famous for loosening up 'stuff' that was happy lying there for decades.

If you boat runs with a slight list (like mine) one engine will pull more crud out of the tank than the other.

Jeff
Click to expand...

My boat actually does have a slight list to stbd. My list angle gauge always shows a slight stbd list even at the slip.

-JJ
 
Trojanman said:
It sounds like you have replaced everything in the fuel system except the anti-syphon valve thats located on top of your fuel tank. If you take her out and she's still starvin' for fuel,you might want to take that off and clean or replace it.
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No anti-siphon valves. I checked to see if I had them.

Since the dip tubes enter directly above the tank, they're always higher then the fuel level. Therefore, even if the fuel line is ruptured, the fuel won't flow uncontrolled.

-JJ
 
.........and there's always the Gerry can test. If it's still not getting fuel, fill a 6 gal. Gerry can and place the fuel line from the carb directly into it and take her out. Just make sure you secure it well or have someone hold on to it so it does'nt spill. But I agree with Jeff, Ethanol does loosen crap up and the sand looking stuff could have been a result of years of sucking stuff up from the tank, you should be ok, just keep an eye on the seperators and change them often.
 
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So I ran her today for the first time with the new Carters, water separators, and inline filters. No stalling issues. I ran it up to 3000 rpm and she felt good. Before the fix, I wasn't able to maintain 2500 rpm for more than a few minutes without the starboard stalling out.

It was either the carb or the sand.

-JJ
 
JJDebeers said:
So I ran her today for the first time with the new Carters, water separators, and inline filters. No stalling issues. I ran it up to 3000 rpm and she felt good. Before the fix, I wasn't able to maintain 2500 rpm for more than a few minutes without the starboard stalling out.
Click to expand...
JJDebeers said:
It was either the carb or the sand.

-JJ
Click to expand...



Glad to hear it. Now go and have a great summer. It's all about maintenance so keep checking the fuel seperators you could be still sucking some bad stuff up from the tank.
 
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