Engine running very rough QSB 5.9L

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So I will likely send the owner and email. I know him and think I owe him that much, but I am going to be looking for another shop to handle my repair and service needs. If anyone has some recommendations in the Tacoma/Pierce County area, I would appreciate it.


You've already invested in some training with your current guys. Might be equally useful to just keep training them...

Just a thought... but by now (or soon, at least) maybe Kurt will begin to figure out that he owes you...

-Chris
 
Your once a year needs for work on a hobby engine will probably always get lower priority that a frequently repeating revenue dependent commercial operation. They should have called you however.
I eventually switched to an independent guy who worked primarily on boats and had worked for the Cummins shop before going out on his own. I got high priority from him after a while and paying my bills quickly.
 
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Your once a year needs for work on a hobby engine will probably always get lower priority that a frequently repeating revenue dependent commercial operation. They should have called you however.
I eventually switched to an independent guy who worked primarily on boats and had worked for the Cummins shop before going out on his own. I got high priority from him after a while and paying my bills quickly.

I agree with you and I actually don't have a problem being a lower priority than the commercial guys. In this region, there are a huge number of commercial boats, and often the local shops here do service and repair work for the commercial fleet in AK. Last spring when I had the boat surveyed another large shop out of Seattle did a last minute mechanic change as well as the scheduled mechanic also had to fly to AK to take care of a commercial fishing boat. So I get it. However, there is no excuse for not calling.
 
Dave if you had a commercial engine like me you're service would probably be better. Definitely better if you were in Alaska.
 
Update:

OK, the shop I have been working with still can't seem to get their act together. The last time I called them, they were still trying to figure out their software issues. The scheduler promised to call me when they had that resolved. That was almost three weeks ago. It has been about 6 weeks since they were last out to my boat and has been almost 3 months since I first called them about my problem. I gave up on them.

I called a Cummins shop in Seattle and they had a mechanic down to the boat today. In 15 minutes he found that my #2 injector is the problem but felt that none of the 6 injectors were all that strong. I can have them replace the one injector or have them replace all of them. The question now is which direction to go. Ideas?
 
I just went thru similar--there is a place in Portland they can send the injectors to get them flow tested.
Of course this requires removing all of them.
Then how much sense does it make to mix older injectors with a new injector?

If you order new ones getting them direct from Bosch was more than $100 less per injector than getting the same injector from Cummins.
 
Dave What is the price of injectors. I think I would go with just replacing the problem injector. Did the mechanic have diagnostic tools to tell him what was wrong?
 
Ok guys, let me explain my thinking based on 50 yrs experience, the early part of that designing multi fuel engines for Rolls-Royce.
I know and understand perfectly well that engines have changed and have operated common rail diesel engines in our family business.


An injector does precisely the same job in a common rail diesel as it does in any other engine, it injects and sprays atomised fuel under high pressure for ignition.

On older engines this action is caused by a mechanically operated injector pump sending a high pressure pulse of fuel up the injector pipe and the injector opening and spraying atomised fuel in for combustion.


In common rail engines the fuel pump maintains a high pressure circuit, engine sensors determine the optimum firing moment depending on speed, load, air temperature and then trigger the injector to open and spray a regulated amount of atomised fuel into the engine for combustion.
The injectors do exactly the same job, its how they do it that is different
and I stand by my previous comment regarding the use of injector cleaner.
Common rail engines can be 'remapped' to provide more torque, speed etc as the standard engine control 'chip' is for general purpose production models, not individual applications i.e truck, van, boat , forklift or digger.
 
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I would have them replace the known bad injector and see what the results are.
 
Thanks for all the ideas.

The difference between replacing 1 and replacing all 6 is about $2,500. That is a lot of money for sure, but the mechanic mentioned that he has found that many times another injector will go not long after another is replaced. I have no way of knowing, but have to take his word for it. He isn't the one selling, or making the quotes and gets paid regardless so he doesn't have much incentive to upsell. If I did have to replace another injector within a couple years, it would cost me a lot more than just doing them all now.

If I had a twin and not a single, I would be more inclined to just have the one injector done.

Taking the injectors out and sending them out for testing and cleaning is a good idea, but that imply means more time without the use of the boat. Given my work schedule, any weekend I can't use the boat is a real loss.

Rebel: They were able to connect the engine to the computer and do some testing. No specific codes were being given but they were able to cut out individual injectors as well as different combinations of injectors. They (the mechanic had a new hire to tagging along. He is experience with boat diesels but new to Cummins specifically) isolated the primary problem to #2 using this method. They also went old school and listened to each cylinder as it was running under these various combinations and again they were able to hear a difference in the #2.

I was a bit impressed how well the engine could run on 3-5 cylinders. Even on just two cylinders (unless one was #2) the engine kept on going.

If I was retired, I likely would see about some other options. Given that boat-time is more valuable that cash at this point, I think I will have them replace all 6. The mechanic estimated that the difference in time to replace 1 vs 6 was about 45 minutes. So most of the cost difference is in the parts, not the added labor.
 
Dave. Well on the positive side, you will get a valve adjustment along with the injectors. And maybe some spares unless they take them for cores. Quite a bit easier access in your boat, then in a truck.
 
A good portion of the cost is getting to the injectors.
Might get a compression test done too while he is in there.

I'm glad to help you spend your money.
 
Since you made up your mind I would take the old injectors to a shop that rebuilds them and but them on board as spares.
 
Since you made up your mind I would take the old injectors to a shop that rebuilds them and but them on board as spares.



Good idea.

Very odd, I took the boat out today just to get out on the water. Strangely enough, the engine started clean, no codes, and ran smooth. I ran it long enough to get up to temp, tested it out up to 2200 rpm and never a hiccup. We dropped anchor for the afternoon and relaxed. Later when we start up to head back, the engine threw a code and ran really rough.
 
the engine threw a code and ran really rough.

Do you own a code reader?

About $150-$200 and as necessary on an electronic controlled engine as a screw driver.
 
the engine threw a code and ran really rough.

Do you own a code reader?

About $150-$200 and as necessary on an electronic controlled engine as a screw driver.


I don't own a code reader. My understanding is that to do it it takes some specialized physical connectors and the appropriate Cummins software.

Much better would be one of the Digital displays that will show all that stuff. They exist, are expensive, it other than running cable, not too hard to install.
 
Cummins electronic engines are supplied with Vessel View which will displace the fault code.
 
2947 WEST 5th Street
Oxnard CA 93030
805-382-6287
800-200-2628

Dave, my best advice is to call the man and get your credit card out. I don't own a Cummins but if I did Tony's number would be saved to my phone.

I have second hand knowledge of several folks(one on this forum) who have had great success dealing with them long distance. All of them would never hesitate to do business with them again.

Good luck repairing your boat.
 
2947 WEST 5th Street
Oxnard CA 93030
805-382-6287
800-200-2628

Dave, my best advice is to call the man and get your credit card out. I don't own a Cummins but if I did Tony's number would be saved to my phone.

I have second hand knowledge of several folks(one on this forum) who have had great success dealing with them long distance. All of them would never hesitate to do business with them again.

Good luck repairing your boat.

Thanks Craig. I did consider calling Tony to found out what it would cost me to have him send someone up. I'm not that desperate yet. He has been very helpful on the sbar.com forum however.
 
Dave

Are you saying that you have a Cummins electronic engine that doesn't have Vessel View? If so how do you read your RPMs, temperature, oil pressure, ect?
 
The injectors for the electronic QSB must be a lot more expensive than they are for the mechanical 6BTA. I replaced all six on mine a year or two ago and the bill was around $1200 including labor.

My mechanic said the cost to rebuild the old ones (very slightly out of spec at ~3500 hours, but no symptoms) was almost as much as buying new injectors, so I went new and keep the old set aboard as a spare.
 
Dave

Are you saying that you have a Cummins electronic engine that doesn't have Vessel View? If so how do you read your RPMs, temperature, oil pressure, ect?

Yes. What I do have is a Tachometer with a small digital window. You can cycle through normal engine information on it such as RPM, temps, pressure, volts, hours, etc... It will tell you if there is an alarm, but it won't tell you what the alarm code is.
Tacometro.JPG
 
Dave

Very interesting. I guess you could add a Vessel View.
 
Dave



Very interesting. I guess you could add a Vessel View.


Yeah, I would really like to do that. Tony Athens has some nice electronic substitutes for the Vessel View that would be great. The expense would not be inconsiderable, but it may be worth it in the long run.
 
Can injectors be intermittently defective? If not,the pesky problem may lie elsewhere.
 
On Common Rail engines not likely....

There were a rash of Bosch injector failures on the 5.9 truck motors..this seems to have been fixed on the 6.7's...

I have read of one injector going bad, shortly followed by several others. There are several companies offering reman Bosch common rail injectors..the Cummins truck forums are good places to search for this

Ch
 
Resolved! Very long post.

Well, yesterday it appears that we found the problem.

In our last episode, the Cummins mechanics had replaced the injectors, which were badly carboned up, but that didn't resolve the basic rough running and fuel knock problem. Further testing pointed to a short in the wiring harness.

After speaking with the Cummins marine manager we decided to have the mechanic (Josh) come to the boat again armed with a new wiring harness, plus I asked him to send along a new fuel pump actuator and fuel rail pressure sensor just in case. He was very willing to order those parts in "just in case".

A day later I get a call from the marine manager telling me that his mechanics had been discussing it more as well as talking with all the non-marine guys at the shop. One of them had related an experience with the same engine but in in a road commercial application. This mechanic said that he had spent 4, 14 hour days working on this engine, doing the same things my mechanic had done, chasing odd codes, replacing the injectors, wiring harness, fuel rail pressure sensor and more. For some reason he finally took the belt off the alternator and the engine ran great. The marine manager said that he was going to send a new alternator with Josh and the first thing he was going to do was take the alternator belt off.

So yesterday that is what we did. Took the alternator belt off and started the engine. The engine did run a little better, less fuel knock, smoother idle etc but still not like it should. Put the belt on again and the engine ran a bit worse. However, the problem has been variable over the past 3 1/2 months so I told Josh that I didn't think that was the right track. Sometimes it would run better than others. So we decided that was a fail and replaced the fuel pump actuator. This had no affect.

Josh, being much smarter than I, said that he wanted to go back to the alternator idea before he replaced the fuel rail sensor then the wiring harness. He decided to completely disconnect the alternator.

I shut down the engine power solenoid which cut the engine off from the start battery. Again, since he is much smarter than I am, checked the positive on the alternator with a multimeter before wrenching on the connections and said that he still had 12.85V to the alternator. This of course made sense since the alternator is wired to the house bank. I went into the aft lazarette and disconnected the 250amp fuse protecting the alternator wiring.

With the alternator disconnected, the engine started and ran perfectly. :dance:

We reconnected the alternator and the problem returned full force. Josh did this two more times just to be sure (he really wanted this problem to go away and didn't want to have to come back).

Sitting in the lazarette staring at the electrical panel I had an idea. A while back, I had changed the start battery charging from the existing Blue Seas ACR to a prior Balmar Duo Charge. The boat has three of the Balmar Duo Chargers, one for the genset battery, one for the thruster/windlass/crane bank, and one for the start battery that had been bypassed in favor of the ACR which looks like it had been added later. I changed back to the Duo Charger since I think it is actually a better way to charge an AGM start battery with a wet cell house bank than an ACR. However, something about that Duo Charger gives the electronic engine indigestion.

I then recalled something that Tony Athens wrote in another thread here on TF a while ago;

With electronic engines, WE NEVER let the engines talk to each other except in an emergency situation and a full understanding what the current issue is. The only common thing is ONE NEG for all with redundancy across all engines.

Being relatively stupid, this didn't make any sense to me. However, my recent experience demonstrates why Tony takes this approach. Very odd things can happen.

So, I have no idea why the Duo Charge creates the issue. It could be related to the health of the the start battery. When it is completely isolated, maybe the Duo Charge doesn't provide enough current to keep the volts up? Maybe it is too much? This shouldn't be the case if the Balmar Duo Charge is operating correctly. The ACR combines the batteries when a charge voltage is applied, either from the genset, dock charger, or the alternator. The engine runs fine with this combined bank.

There is plenty of power in the start battery, it fires the engine up easily. It is just when the engine is running that there is a problem. At least now I know what was causing the problem and have an engine that is running well. I can try to answer the questions as to why the Balmar Duo Charge was creating the issue another time.
 
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