[Mike Schmidt]

It’s the little separate oring shown in this picture.  It was actually included in the FS1000 and not the FS19513.

 

 

[Mike Schmidt]

Ok, thank you – I’ll check this next.  

Also, what do you think about the small bubbles in the squeeze bulb hose line?  Seems to me that the Racor introducing air would be unlikely, so I’m guessing these bubbles are not the likely culprit…

[Mike Schmidt]

Well, I’m at a complete loss here.  My 330 6BTA engine is only hitting 2400WOT with typical white smoke (nothing crazy), where it was previously hitting 2850 with the boat similarly loaded.  I went through Tony’s “low power troubleshooting” and mostly everything checks out (exceptions here is where I really need help!).

1. Throttle and fuel solenoid control linkage checks out
2. Racor AND on-engine fuel filters replaced
3. Added a fuel vacuum gauge after filter change and levels our fine (~3Hg)
4. Checked for air leak in fuel line from tank to Racor (added section of clear hose to check for bubbles).  No bubbles seen here
5. Checked for air leak between Racor and engine (to see if Racor was introducing air).  I checked this by installing the squeeze bulb priming system which included a clear hose bypass to the squeeze bulb.  NOTE that I did see some bubbles in this line, but after researching the issue it seem that it might be normal/acceptable to see some bubbles due to low pressures created in the fuel due to flow through fittings.  
6. No fuel leaks are appearing at the combo block or connections at the engine
7. I wanted to install a pressure gauge at the on-engine filter but I didn’t have the right adapter to take out the port plug (frustrating)!  I’ll get this done, but I don’t even know what PSI to look for so any help here would be appreciated.
8. Strobed tack and is accurate

After all this there is no improvement.  What do you all think – especially regarding #5 and #7?  If air in the fuel line is not an issue and the PSI checks out, then what’s the problem???

Also, not sure if this is relevant, but I did add the fuel cooler bypass shortly before this issue presented itself.  I don’t know if the engine every operated correctly after this mod because I think I just tooled around at ~1300RPM a few trips out over the course of a few months, then then once I opened up to WOT I noticed the problem.  When running slow there are not symptoms.

 

[Mike Schmidt]

One more question before I get started, though.  My fuel is about 1.5 years old and I never put in any additives or stabilizers.  Is it likely that the fuel is bad?  I see no water in the Racor bowls.

[Mike Schmidt]

Yep, I know.  My initial question had to do with having the wrong on-engine filter installed, but now that I know that’s not the issue I’ll go through all your troubleshooting tips.  I’ll report back soon once I have some data.

[Mike Schmidt]

Well… I see now that the FS1280 is the correct filter.  I guess I need to go through the diagnostic steps to figure out the cause of the lack of WOT.  I’ll start with a vacuum gauge between the engine and racor and fuel pressure gauge.  Another interesting thing is that this all seemed to become a problem right after I deleted the fuel cooler.

[Mike Schmidt]

Unfortunately I can’t post a pic now, the boat is hours away. But, the hose looks perfectly fine. The only thing is that I had to put a kink in it to get it on the nipples, and then I straightened it out. I’m just concerned that bending it like that did some internal damage to the hose. After I kinked it, it would bend over with little force after that, so it seems like there was some effect to the hose… whether that means the hose is at risk of bursting/leaking, that’s what I’d like to know.

[Mike Schmidt]

From the looks of it you have the exact same boat and configuration as me, a Meridian 411 with 6BTAs. I have installed a fresh water flush system running into the raw water pump outlet bung. I flush it after every outing for about 5 minutes per engine without the engine running and not problems.

[Mike Schmidt]

What I mean by “charging profile” is the voltage at which the alternator charges the batteries. Since different battery chemistries require different voltage (e.g., LA = 14.2v-14.5v vs AGM = 14.6v-14.8v absorption charge), the alternator will only provide a correct and complete charge if it’s set up with a three-phase external regulator set to the correct profile (agm, lead acid). This is the information I’m working with that makes me question whether or not an external regulator upgrade my 19SI alternators would help in getting my house bank charged faster and to a full charge. I’m not even sure what is involved to convert the 19SI for external regulation, so any information about that would be great as well!

As for my monitoring battery terminal voltage, I’m using a Victron BMV-712 monitor.

[Mike Schmidt]

Tony Athens wrote:

This looks like what I have seen on some “Sea Rays” ? Underwater exhaust and a bypass out the stern?

Yep, same setup here (this is a Meridian). So if the exhaust is downhill from the mixer, can I do an engine-ff flush or is this a lift muffler?

[Mike Schmidt]

Another option you might consider that is simpler, easier, and quicker while accomplishing the same thing would be to screw in a 1/2″ stainless ball valve into the lower water intake port of the raw water pump. Screw a garden hose quick connect to that and you’re done!

[Mike Schmidt]

glenn111 wrote:

I use Dremel with cutting accessory. Precise and cuts through the wire also.

Aren’t you worried about cutting into the pipe? Even a shallow cut could compromise the seal on the new hose…

[Mike Schmidt]

Rob Schepis wrote:

Razorknife…..

Yep, I used that but it doesn’t get past the wire reinforcement. It helped a little to loosen things up a bit, but still was practically impossible.

[Mike Schmidt]

You don’t need the tee after the water pump. You can simply thread in a 1/2″ bronze valve to the female threaded outlet port on the water pump (the top 1/2″ port that currently has a plug in it). Seems to me that pumping cleaner into that port will bypass the impeller.

[Mike Schmidt]

Tony Athens wrote:

Go Fishing.. But, don’t do it again–

Tony

I like that answer!

There is a zero chance of that happening again – ever!

[Mike Schmidt]

Rob Schepis wrote:

Serviced three years ago and someone forgot the o-rings!

Are you going to investigate the engine as to saltwater ingestion?

Have you took a look at the grid heaters – let’s hope that they look anything like that core….

Is the condition of grid heaters a good indication of whether or not an aftercooler is leaking? Seems like a good quick/simple diagnostic checkup item to add to the PM schedule.

[Mike Schmidt]

Rob Schepis wrote:

Agreed on eliminating the fuel connections at the combo block. The oil connections at the block are not as pesky but the fuel connections will leak.

Why is it that you think the fuel connections on the combo block will leak? Assuming the hose nipples are screwed in plenty tight with rectorseal, it seems to me that there’s no reason they would ever leak…

[Mike Schmidt]

I ran into the same problem. You’ll be able to relocate your fuel return line obviously with the included fittings, but the supply line will have to stay where it is on the distribution block. No big deal… I don’t think the presence of the distribution block matters at all anyway.

[Mike Schmidt]

Rob Schepis wrote:

With the gears you have the issues of the extra shaft and ratios between the two gears and don’t forget that the printed engine HP output tolerance from Cummins is +/- 5% … mathematically that could be your 10% right there. If it’s always been constant I think that in itself is your answer – it’s “inherent” …. it’s not an issue that has developed nor does it need attention/correction.

Do you think it would be warranted to install an EGT/pyrometer to balance the engines? I’ve read on some forums that some people say that the only way to truly balance engines (so that their “effort” is within the right tolerances) is via an EGT. I’d hate to think I’m overworking the port engine (even though it’s tach synched to the stbd)…

[Mike Schmidt]

Rob Schepis wrote:

Mike Schmidt wrote:

Is this what you would recommend doing every single time (1x/2 years)?

No, if original, never been done, on like a 10+ yr old engine.

Makes sense – thanks

[Author]

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