Fuel Pick up tube problem

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kjoverbeck
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Re: Fuel Pick up tube problem

Post by kjoverbeck »

That all makes sense except that when I topped off both tanks at Green Turtle it only took 72 gallons.
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Re: Fuel Pick up tube problem

Post by kjoverbeck »

Thanks for all the replies. This issue got me promoted to 1st Mate!!
lgeller
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Re: Fuel Pick up tube problem

Post by lgeller »

Problems with the pick up tubes were the first indication of the trouble that we had on PLUSH TOY. It was after seeing the tubes that we tested the fuel and determined that we had received some diesel mixed with gasoline.

With regard to cleaning the tanks, I used LUK FUEL here in Florida. They did a very thorough job emptying and scrubbing the tanks.
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Re: Fuel Pick up tube problem

Post by Nick »

Well, well, this thread was an interesting find! We bought Rising Tide (now Catsaway) from Kent earlier this year. She’s been running great until a particularly rough passage across St Andrews sound two days ago. Soon thereafter the starboard motor struggled to get above 3,000rpms. I changed both the primary and secondary filters (the Racor filter element looked like a slightly twisted can), but had no improvement. I then swam under the boat hoping to see something wrapped around the prop, but nothing. After talking to a mechanic (and reading this thread!), I now believe the issue is probably something between the fuel tank and the Racor since the port side motor continues to operate happily.

Again, thank you to all those that came before and continue to post on this invaluable forum. More to come!
Nick & Barb
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Re: Fuel Pick up tube problem

Post by duetto »

hi,

could the deformed racor be from too much vacuum. in an earlier post mentioned vacuum gauges. do they read normal?
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Re: Fuel Pick up tube problem

Post by Nick »

Yes, good point, vacuum reads high. I think it’s all driven by restricted fuel flow. I suspect the issue may be as easy to resolve as disconnecting the fuel line at the fuel tank, hooking up my dinghy pump to the fuel tank pick up and pumping some air down the tube and into the tank to clear the pick up. That’s my next step anyway! Cross fingers it’ll be THAT easy!
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Re: Fuel Pick up tube problem

Post by duetto »

i would also check the inlet to the racor. i read about a clog at the inlet. i think there is a ball shutoff of some sort. good luck and report back.
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Re: Fuel Pick up tube problem

Post by Nick »

After checking the fuel system from tank pick up through filters to motor, cleaning the turbo compressor and cleaning and testing all the injectors (they were dirty), the problem is not resolved. Next step is to rebuild the fuel injection pump. As an aside, I called a Yanmar dealer and was told there are NO new injection pumps in the US and only seven on the shelf in Japan for my motor. Fortunately, the boat still runs so we’re heading further south to leave her with a known mechanic and free dockage while we fly home for the holidays. At least we’re still boatin’.....and I’ll have a great Xmas present for Barb..... a shiny new rebuilt fuel injection pump haha! Will update results when complete.
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Re: Fuel Pick up tube problem

Post by Cat Daddy »

Nick,
Mine had a restriction in the elbow that screws into the tank, the screen that has been mentioned earlier is in the elbow on my boat. I don't know if it was always inside the elbow or migrated up the tube over the years, but that is where it is. During a long crossing from Clearwater to Destin the vacuum built to a unbelievable level and the engine kept running. After daybreak I changed filters but the high vacuum returned quickly. Having vacuum gauges at the lower helm greatly helped troubleshooting the problem. With a light shining up the pick up tube I could see the gunk lodged in the elbow. Back flush with brake parts cleaner and problem solved.

Your problem sure sounds similar and because it was after a crossing I think you have a restriction ahead of the Racor. The deformed filter is another indicator.

If you are going to be at the rendezvous I would like to meet and discuss.

Good Luck,
Rafe
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Re: Fuel Pick up tube problem

Post by thinwater »

Was it a genuine Parker/Raycor element? They should NEVER distort under vacuum, and I have changed many hundreds in industry, many of which were tragically dirty and high vacuum.

If it deformed, dirt got past it. If the injector pump is bad, that may be the reason. There should be a filter on the engine, but bugs can get through any filter, even 2 microns, and running running starved is not good for pumps either. Sounds like it would have been smart to shut the misbehaving engine down before more damamge could occur. Never run equipment that is operating incorrectly when you don't know why.

There may also be restriction up stream that caused the vacuum, such as a dirty tank and multiple clogs in the line. It can always be more than one.

Sounds like a dirty tank. First the line clogged, then the knock-off filter collapsed, then the injector pump was damaged by running starved. A cascade of problems. The only cure for a dirty tank is cleaning with elbow grease. Forget fuel polishing, it's just a band-aide.
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Re: Fuel Pick up tube problem

Post by Nick »

I have looked at every piece of the fuel flow from tank to engine and return including pulling the pick up blowing air through lines and watching flow. There just don’t seem to be restrictions. The filters used were genuine Racor and I agree should never deform, but it did. Have had a Yanmar specialist go through troubleshooting (even commented the fuel flow seemed great) and we are down to the fuel injection pump. WIth respect to operating the motor when you haven’t diagnosed the issue, Yanmar specialist said, with respect to this issue, it was ok provided I didn’t run rpms up to where motor struggled. We are keeping rpms low and motor running like a sewing machine (especially with cleaned injectors!).

I will be getting the problem resolved in the coming month and will report back.

Unfortunately, we are not going to be able to attend the rendezvous as we plan to return to the PNW for a couple of weeks. We plan to attend in future. Rafe, we met 3 years ago at the Gulfport Municipal Marina and, if you’re still there, we’ll be there tonight and tomorrow night before leaving Sunday for Cortez.
Nick & Barb
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Re: Fuel Pick up tube problem

Post by kjoverbeck »

I would like to add that these are Racor 500s not the spin on filters. I don't quite understand just what is collapsing. The cartridge inside or the filter body itself. Definitely an interesting mystery.
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Re: Fuel Pick up tube problem

Post by Cat Daddy »

Nick,
Sorry for not checking back sooner. I think I remember you on a Bayliner, congrats on a great choice on Kent's pride and joy. I am at home and my boat is in Ft. Myers, maybe we will see you along the way or the '21 rendezvous.

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Re: Fuel Pick up tube problem

Post by Nick »

Well, the verdict is in and solution was unbelievable! Different mechanic pulled the Racor off mount, flipped it upside down then right side up and problem solved. There is a check valve in the Racor. The rough passage may have stirred up a little grit and stopped the free movement of the valve....or at least stopped it from allowing higher fuel flow volume associated with more throttle.

The filter distortion was caused by the fuel pump trying to draw fuel through Racor against the partially stuck check valve. Bottom line, fuel pump is totally fine and even I could have solved this issue in minutes! Now I know. For the record, I think John on Duetto diagnosed the issue earlier on this thread!
Nick & Barb
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Re: Fuel Pick up tube problem

Post by Lyons Pride »

a simple way to isolate a possible fuel restriction would be to bypass the filter with some diesel gas from a portable tank. If bypassing the filter system which would also include the tank being bypassed as well you can check if the engine runs strong and at high rpm......if the engine runs fine from the portable gas tank then the problem is from the filter back to the tank. If it doesn't run well after you bypass then the problem is in the motor parts. I hope this helps.

Kip
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