Vibration

CurrentSea

CurrentSea

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So here is the scenario.

Still on first tank of fuel from last winter.
Was trying to get rid of it, then change filters and put in fresh fuel. I was low on fuel, down to a 1/4 tank but should be about 60 gallons.

Boat was running fine and all of of a sudden and a get decrease in power on port motor and a shudder/vibration.

Shut it down. Restart and vibration. I am thinking POD at this point. Something on it? I go in reverse and try to go forward and vibration. Still thinking POD.

Limp home, one starboard motor and go to start port motor and it won't start now. So now i am thinking it's not pod, it's fuel. Clogged fuel filter and the vibration I feel is not from pod but from the motor because it can't get any RPM's. Make sense?

My next step plan

- Add fuel from some portable tanks. Hoping 10 gallons be enough.
- Change both fuel filters. Actually plan to change all filters at this point.
- Prime and bleed air
- See if it starts.
- Get to fuel dock and load up both tanks.
- Take it out and see if it vibrates.

If I plugged my filters is there any other concerns?
 
I would not add any fuel. Change filters then run it and see whats up.

There could be junk in the tanks and it is better to deal with low fuel.
 
I did have a issue with the other tank and genny where it clogged the tank intake.
So there probably is some junk in tanks.
I guess I can remove access panel for tank to see how much junk.

What is best way to get rid of junk as I would rather clean out before I clog up more filters?
 
That's what filter are for. If it runs Ok with new filters i would run with low fuel on some nice bouncy conditions to stir up and filter out the junk.
 
I shouldn't polish it?
At $80 a motor, I can run thru alot of filters.

Getting back to original question as well, does it make sense that vibration I feel is from motor and not pod if clogged filters?
 
Filters are expensive and ruined outings in mid summer $uck. I would have the tank cleaned.
 
That's what filter are for. If it runs Ok with new filters i would run with low fuel on some nice bouncy conditions to stir up and filter out the junk.
 
No harm in polishing the fuel especially while you have low levels. BUT are you sure that is the problem????
 
Without a VODIA diagnostic device, I think I would start with 2 things.

-Empty the primary fuel filters into a clear container through a cloth to see if it is obvious there is fuel quality problem [ water, tank debris, microbes [do you always add biocide at fill-up, or wait until there is a problem as many owners do?)],etc.. Is there even fuel in the filters?

-If there is nothing obvious above, I'd jump in with mask and U/W flashlight and inspect the pods just to not have to still wonder about those . BUT- the pods should not be affecting start-up.

You have 2 diesels. Do they each have their own completely independent tank?

Or do they either share the same tank, or run off 2 tanks BUT A CROSSOVER VALVE IS LEFT OPEN, so they still may be supplied by some fuel from either tank?

If 2 tanks with open crossover, fuel will tend to be be drawn by both engines via the path of least resistance, which usually means they will draw more & faster from one tank than the other. Besides the potential problem of contaminated fuel in on e tank being shared by both engines, when one tank is drained fast than the other and level dips below the pickup, both engines will then be sucking air from that tank , since the remaining fuel in the other tank has more resistance.

If either there are clogged primary filters or air was entrained in fuel until only air was supplied their would be a loss of power and great vibration.

I'm only guessing a change of primaries (fill them if possible), fill all tanks, close any crossover , and if the engines are not self purging , do that, and your engines will start /run fine.

I wouldn't get involved with polishing unless filter clogging was an ongoing problem, but personally if I had diesels I would add biocide or preferably use Valv-tect fuel which has it & stabilizer. ( I do use Valv-tect stabilized gas 90++% of the time- w/never a fuel quality problem ever.)

I think you can safely rule out the spark plugs . :)
Edit : since this is a diesel boat, it might be good to clarify , by "crossover" I was referring to tank pickup and engine supply line crossovers only, not tank level-equalizing crossover connections only diesel tanks can have at the bottom .
 
Do you have this type of dual-filter setup for each engine yet?

http://www.lfsmarineoutdoor.com/rac...dual-manifold-turbine-diesel-fuel-filter.html

Makes it simple to change(switch) filters in seconds if you have any suspicion of clogging ( as would be indicated by fuel-line vacuum gauges on the engine side of the primary filters. )

Here are 2 types of very handy vacuum /restriction indicators:

http://www.defender.com/product3.js...uge-kit&path=-1|311|2349076|2349087&id=549139

http://www.defender.com/product.jsp?path=-1|311|2349076|2349087&id=1771858
 
Never prefill the fuel filters on a electronic diesel ..

Dave def remove filters and crack em open. That will tell the tale. U should have racor prefilter and on motor filter. change them all.

If it turns out u have **** in the tank . CLEAN IT OUT .. last thing u need is that coming back to haunt u in a year or two when u run low on a trip in **** weather and u loose RPM .... NOT GOOD

and yes ... dirty plugged/ water filled filters can cause all kinds of odd things on an electronic fuel injected motor .

Rob
 
Seperate tanks.
Each holds 137.5
Both show fuel left.
I think filters are plugged.
I have UL filters, one is 10 micron other is 2 micron, no bowls.
UL filters use metal bowls, so you can't see what's in there

Will clean out, add fuel just in case, and advise.
No polish yet.

I add biobor now and then, gonna start doing every tank.
 
Dave u can see what's in the bowls. The metal is a heat shield is all.

Rob
 
quote:
Originally posted by Robski97

Dave u can see what's in the bowls. The metal is a heat shield is all.

Rob

Click to expand...


Unless Dave possibly has a spin-on type with metal bowl( which has a brass drain plug) rather than the turbine type?

Rob - Would you kindly elaborate why one should never pre-fill primary filter/separators with electronically-controlled diesels? I haven't heard of this.
 
quote:
Originally posted by Robski97

Dave u can see what's in the bowls. The metal is a heat shield is all.

Rob

Click to expand...


Negative.
For some reason my boat was made with all metal solid filters. I have a metal bowl on the bottom with a drain plug but no visible bowl.

When i asked Regal about this they said that ABYC requires certain engine rooms to have this type of filter to meet UL (underwriter lab) standards. Makes no sense to me and I looked to change them but when I saw the cost I decided it was not worth it. I just spin off the metal bowl to see water or junk.

Either way, I am changing all filters.

It does say on the filters not to pre-fill. The concern I was told was more around contamination. When you fill some fuel gets on gasket and could get contaminated. I have changed my filters before and I usually do fill them up just to make it easier to prime.
 
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