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Old 11-30-2010, 12:08 PM   #21
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RE: Small Surges in RPM Every Few Minutes.

Yep...you don't want to let that one go...it will rear it's ugly head and bite you at the most inopportune time!!!
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Old 12-01-2010, 04:41 AM   #22
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RE: Small Surges in RPM Every Few Minutes.

"Temporarily put a piece of clear tubing in the fuel line just before the lift pump and look for bubbles."


The better way to do this is to go to a refrigeration supply house, and ask for an "Armored Sight Glass".

This will come with a male and female fitting (ask for your size) and you can see bubbles in the fuel as desired.

About $15.00 the last time I got them.
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Old 12-01-2010, 05:15 AM   #23
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RE: Small Surges in RPM Every Few Minutes.

It's actually easier to see small bubbles through a 6 inch or so length of plastic tubing that can be bent to form a high spot to collect them.

And for the OP, you don't have to run the engine. Shut off the fuel valve at the tank disconnect the fuel line where it fits the lift pump, attach a hand operated vacuum pump like you find in the auto parts store and pump.

Just make sure you keep the end of the fuel line above the filters and keep liquid in the tubing so you can see bubbles. It might take a few tries to get this right. If the vacuum stays constant for a few minutes with no bubbles, you have some other problem ... and that will make for a longer thread.
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Old 12-01-2010, 06:43 AM   #24
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Small Surges in RPM Every Few Minutes.

How do you keep from sucking fuel into the vac pump? To keep fuel in the line, wouldn't you want it below the filter level?

I'm having trouble picturing the process you are describing in my mind.

Are you talking about a pump like this:

http://www.autozone.com/autozone/acc...fier=2080_0_0_

Cheaper version:

http://www.autozone.com/autozone/acc...uestid=1076515

-- Edited by GonzoF1 on Wednesday 1st of December 2010 07:45:38 AM

-- Edited by GonzoF1 on Wednesday 1st of December 2010 07:47:16 AM
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Old 12-01-2010, 07:06 AM   #25
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RE: Small Surges in RPM Every Few Minutes.

Gonzo*

What size of fuel filters - Racor 500 or 900?
*
Have you changed your primary*filter from 2 back to 10 micron with new rubber O rings*? Have you recently changed your on engine filter with new O rings too?* Stop trouble shooting until you check off these two steps.

You may want to go to boatdiesel.com for hundreds of similar posts and solutions
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Old 12-01-2010, 07:08 AM   #26
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Small Surges in RPM Every Few Minutes.

Hiya,
** I think I understand what Mr. Rick B is suggesting but rather than putting that 6" of clear hose into the fuel line, shut off tank, disconnect the fuel feed from the tank side of the pump, attach a LONG (3' or so) piece of clear tubing to the open end of the fuel line and connect your vacuum pump (VP) to the open end of the plastic tubing.
** Hold the*VP as high as you can and pump the system down.* That 3' of height SHOULD give you a "buffer" to keep the fuel out of the VP.* Check for constant vacuum.
** To check for bubbles, allow the fuel to rise, say 1' up the clear hose and make a 360 degree loop in that fuel filled line close to where it attaches to the solid line (you may have to tape that loop to maintain it's*"loopy" shape).* Again apply vaccuum with the VP held high.* If any bubbles are generated they SHOULD collect in the top of that fixed loop.
** Clear, or still having trouble?* I wish I knew how to attach a diagram as I think it would be much easier to visualise my explination.

-- Edited by RT Firefly on Thursday 2nd of December 2010 05:51:50 AM
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Old 12-01-2010, 07:13 AM   #27
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RE: Small Surges in RPM Every Few Minutes.

Yeah, that's the pump.

If there is no leak or a very small one (which it sounds like) you won't suck any fuel out of the line as long as the top of the clear plastic tube and the pump are above the filters. Picture sitting with the pump on the edge of the engine hatch with your feet dangling and a clear tube leading down to the fuel line at the lift pump, suck up enough fuel to mostly fill the tubing but leave an air space above the fuel level. When you pump with the tank valve shut it will pull a vacuum on the line from that point without moving any fuel.

Hope that makes it more clear. Make sure the filters are full or you may suck up some fuel as any air in the canister expands. I suspect that just doing that might reseal the filter housing(s) and cure the leak.
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Old 12-01-2010, 08:54 AM   #28
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Small Surges in RPM Every Few Minutes.

Ahhhh hahhhh! NOW it makes sense. Thanks guys (I'm assuming).

Mr.White, It's a Raycor500 and I have not changed out to the 10mic filter yet. I'm a "weekender" and probably won't get around to tackeling this problem for a few weeks. Although, come to think of it, I don't think I changed the o-ring last time.

There was a period of time in the spring where I was having some starting issues and replaced the filter more often than needed, so really, the current 2mic filter only has MAYBE 50-70 hours on it. Still, I'll get on trying to track it down sooner rather than later.

-- Edited by GonzoF1 on Wednesday 1st of December 2010 09:54:29 AM
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Old 12-01-2010, 06:57 PM   #29
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Small Surges in RPM Every Few Minutes.

Quote:
GonzoF1 wrote:

Ahhhh hahhhh! NOW it makes sense. Thanks guys (I'm assuming).

Mr.White, It's a Raycor500 and I have not changed out to the 10mic filter yet. I'm a "weekender" and probably won't get around to tackeling this problem for a few weeks. Although, come to think of it, I don't think I changed the o-ring last time.

There was a period of time in the spring where I was having some starting issues and replaced the filter more often than needed, so really, the current 2mic filter only has MAYBE 50-70 hours on it. Still, I'll get on trying to track it down sooner rather than later.

-- Edited by GonzoF1 on Wednesday 1st of December 2010 09:54:29 AM
"2 mic filter only has MAYBE 50-70 hours on it."
I had a complete engine shut down due to fuel starvation from a clogged 2micron fuel filter at 80 hours of use. And this was only two months after a 500 mile delivery run in which we were burning and buying new fuel frequently, so the fuel wasnt that old.

Do not trust the filter when you are having fuel issues.
R.
*


-- Edited by ralphyost on Wednesday 1st of December 2010 07:58:21 PM
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Old 12-02-2010, 04:37 AM   #30
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RE: Small Surges in RPM Every Few Minutes.

www.mityvac.com/pages/products_hvpo.asp

This is a hand pump that will pull almost 28 inches.

Useful on board for priming a diesel, or every 2 or 3 years to replace the brake fluid in the family car as PM.
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Old 12-02-2010, 04:58 AM   #31
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RE: Small Surges in RPM Every Few Minutes.

Hiya,
** Edited my post (changed VC to VP) so it should make more sense-hopefully.* Mr. ralphost, I fully agree the filter SHOULD be the first suspect when experiencing fuel problems but simply changing from a 10 to a 2 micron filter should NOT cause problems on the OP's motor.* I interpreted his post being that as soon as he changed from a 10 to a 2, he started experiencing problems but after 70 hours it could quite possibly be a clogged 2 micron filter.* That being said, how many hours on the SECONDARY* filters and what size are THEY?
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Old 12-02-2010, 06:26 AM   #32
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Small Surges in RPM Every Few Minutes.

FF, now c'mon - who replaces their brake fluid every 2 or 3 years?

RT, you are assuming Gonzo used theright racor filters. The**500s are not always a good fit for the*someolder racor filters - so says racor. And Gonzo's problem started soon/immediately after his latest primary filter change using 2u primaries*---------- and could he*have*overloaded the on engine filter with crud from the primary during the change ------*he did not have the 10u filters he had used in the past ------------ and he possibly did not changeout the racor*O ring or added a second one -------- and a 2u primary is putting a lot of faith in diesel fuel which most suppliers only filter to 30u, if that.

But, if I were a dirty shirt boat mechanic for hire, I would not suspect the filters since the owner says they are fine. I would instead look over and check the rest of the system first and turn in a big trouble shooting bill.

-- Edited by sunchaser on Thursday 2nd of December 2010 07:46:53 AM
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Old 12-02-2010, 07:08 AM   #33
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RE: Small Surges in RPM Every Few Minutes.

Hiya,
** Mr. sunchaser.* As you noted (and rightly so) there are a LOT of "ifs" and I don't know the circumstances of Mr. Gonzo's situation other than the surging which suggests some sort of fuel system problem.* I stand by my earlier statement that a clean 2 micron primary filter, properly installed, alone, SHOULD not cause Mr. Gonzo's symptoms and that a thorough going over of the COMPLETE fuel system is in order, starting with the simplest things first.
** I don't think this "problem" necessitates the hiring of a mechanic as a fuel system compared to an electrical system is pretty simple and Mr. Gonzo can only benifit by increasing his knowledge of HIS boat by doing it himself.
** There have been a lot of very good suggestions thus far and I anxiosly await to hear what the cure will be.
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Old 12-02-2010, 09:15 AM   #34
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RE: Small Surges in RPM Every Few Minutes.

"And Gonzo's problem started soon/immediately after his latest primary filter change ..."

I think Mr. Gonzo should weigh in on that. I can't find any such statement anywhere under his name.
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Old 12-02-2010, 09:25 AM   #35
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RE: Small Surges in RPM Every Few Minutes.

Gonzo wrote:

"...the current 2mic filter only has MAYBE 50-70 hours on it."
************************************************** *************

My trusty mechanic tells me that I should change my Racors even if they have low hours if they have been in the boat for several months. He says that they can deteriorate over time plus get dirty with use. I once had a Racor 1000 go bad with only 20 hours but it had been in the boat for 6 months.

My 2 cents again.
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Old 12-02-2010, 10:53 AM   #36
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RE: Small Surges in RPM Every Few Minutes.

Quote:
RickB wrote:

"And Gonzo's problem started soon/immediately after his latest primary filter change ..."

I think Mr. Gonzo should weigh in on that. I can't find any such statement anywhere under his name.
Then weigh-in, I shall... Oh, and please y'all... Call me Tom Gonzo is an old nickname from my audio engineering days.

*

Ok... So... Where was I... Oh yea - There are a lot of unknowns on my part. I can't assume, confirm, or verify the specific time these little surges began. TBH, I just didn't make a mental note of it the first time it happened. I have been feeling them for a while, but as I am still sorta new to all of this and am still becoming "in tune" with the zen-like awareness of boating. Especially with diesel technology and what to look for, feel for, and listen for.

I know it's been going on for a while, but whether it has been 6 months, 8 months, or a year... I would be lying to you if I said I knew for sure. That was the purpose of this thread. It was to sniff around your brain stems to learn what I could about a problem that has finally made it to the top of my "ask-the-smart-guys-at-the-trawler-forums-list-about"

I can say that it DOES appear to be increasing in frequency. I think I was timing it last week at about seven minutes between surges. I can say that I use Bio-Side last year...* it was too long ago (August) that I topped off the tanks for the first time. Not too long after that, I replace the filter a couple of times and I had the injector pump cleaned and checked while chasing another unrelated problem that ended up being the starter. The most recent "change" was the unintentional move to the 2mic filter.

What does all this mean? Well, to me, nothing. It's just a pile of note-worthy things I have worked on in the past year. Do any of them REALLY point to the problem I am feeling? Perhaps none of them, or a combination of a few, or ALL do, but like I said, I can't point at a moment in time when it started happening for sure. Thus, it's time to ask my team for possible solutions and tests to try and find out where to start looking.

I certainly hope it's just a filter,* but with history as a barometer, I ain't holding my breath. I'll start looking... break something major in the process... figure out a way to throw hundreds of dollars at the problem... only to find out there was a kink in some line that I didn't see the first 25 times I looked. Still, I hope that the real fix will require a a big bottle of wine, a few strippers, some baby oil, silk sheets, and a trapeze.

Anyway, this is quickly turning into a Marin-length post, so I'll wrap it up.

I now have a good list to start on to try and work this problem out. My sincere thanks for that. Please keep the thread going if there is more to add. I am try to absorb information about marine diesels when I can. There ae so many systems I still need to learn about (san the waste tank and I loathe the day I have to go down THAT road). I really have to learn them AS they become problems because I would quickly get swamped if I tried to learn it all right now. So I live-and-learn. I still have the genset, reverse-cycle A/C, and like I said... the waste system to get on the radar. All part of the excitement of boating, it seems.

I know this was a lot of BS that didn't help any, but it was fun to write.
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Old 12-02-2010, 11:18 AM   #37
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RE: Small Surges in RPM Every Few Minutes.

Well, fwiw Tom, I am an alumni of the same mechanics school as you. Take it apart, break the part or something nearby, cut your hand in the process, throw money and time at it, realize there was an easier way to do the job, put things back together and finish the job. Get a drink and pat yourself on the back. Then, come Monday morning, wonder why all of your muscles are rather stiff and sore. The strippers etc. sounds like a good ending.
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Old 12-02-2010, 12:13 PM   #38
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RE: Small Surges in RPM Every Few Minutes.

I change the primary Rocor filter and the engine filter every year. However, when we first got the boat ever 100 hours which took several years and they where still good.* So how long can filters last sitting in diesel?**The rule of thumb is*one year or 100 hours which ever comes first.


*
One of the first thing I had done was added an electric fuel pump help bleeding the engine and to transfer fuel from one tank to another as the Webasto draws from the port tank,* the 671 draws from the starboard and the gen set from the middle.* I try to keep each separate and filtered/polished.* The reason is if there is a fuel problem I can keep it in one tank, change to another tank, and polish/clean the one tank.*
*
It would seem you if the leak is before the Racor filter you should be able to see the bubbles in the bowl.* I look at a diagram on a Racor filter, the fuel first goes into the sediment bowel then up into the canister/filter.* So it would also seem like air would be trapped at the top as the in and out connection is in the middle of the filter?* So if you can not see bubble and/or no air is trapped in the top, then it*should be*after the Racor filter? The reason I bought two 180 gph filters is to filter the water/sediment and trap the air?* At least that is what I was told when I bought them?
*
Anyway, I would check and do the simplest before taking the fuel lines apart. If it persists I would call a diesel mechanic.* The more you change things the hard it will be for a mechanic it figure out, and while he is there ask him to give the engine a general check over as you can learn a lot by asking questions and watching. **I have my diesel mechanic double check and do things so if I really need him at least he knows who I am and familiar with the Eagle maintenance.****
*
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Old 12-02-2010, 12:53 PM   #39
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RE: Small Surges in RPM Every Few Minutes.

Hiya,
** No Phil/Fill you won't be able to see bubbles in the Racor bowl.* Stick to what you KNOW-manicures and dresses!
** Mr. Gonzo take note of the question marks Phil/Fill puts after his statements-as USUAL, he hasn't got a clue.* Ignore his advice.
** The suggestions made by the other listees are all valid and again, fuel systems are pretty simple so the solution should be simple as well.* No need to call in a mechanic just be systematic in your approach.**Do/change ONE thing at a time.* If you do/change multiple things and effect a succesful repair, you won't know what the "fix" was.
** I would suggest you purchase a cheap set of flare nut wrenches...
http://www.harborfreight.com/catalog...e+nut+wrenches
* They're far superior to regular wrenches when working on fuel fittings as they less likely to round off*a fitting.* Better still, for $10 buy 2 sets.* Remember: Righty tighty, lefty loosey.
** Start at one end of the system and work your way to the other, again doing ONE thing at a time.
** Mr. Gulf Comanche.* Mr. Gonzo NEVER suggested the trapeze etc. was the ending!
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Old 12-02-2010, 01:25 PM   #40
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RE: Small Surges in RPM Every Few Minutes.

I already have "brake line" wrenches

One thing I mentioned earlier, but forgot to re-mention is the small leak at the top of secondary filter. Hard-line banjo bolt AFTER the lift pump... I wonder if that might be the source of the air leak. IIRC, I didn't have the right size o-ring in the secondary filter kit when I changed it in the spring. However, I still have a small leak that requires me to put a small piece of absorbing mat there every couple of week.

Would a leak there build up and then surge enough air into the pump to have it surge?

It all seems to be coming back to me know. I wonder if I recall the surges beginning then? I'll ask The Carbon First Mate Unit. She might know when it started.
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