6BTA Spool Up Issue

[siwicki]

Dear Tony,

Carolina Classic 28 with a pair of 6BTA5.9 M3 330HP. Roughly 2200 hours on the engines with no major problems. Cummins did a full service at 2000 hours which included adjusting the values. I generally put about 60-80 hours a year on the engines. I also have your water pumps on for the last three years.

I had a strange problem with my starboard engine that happened on my last trip in December, the afternoon before I had to haul and winterize for the season. I am hoping you can give me some ideas where to start in a few weeks as I prep for launch.

The bottom line is the starboard engine seems to be operating fine at idle and troll, but the turbo won’t spin up and it smokes like hell when I try to take off. So let me explain the day as this quickly progressed to give you some background.

It was about 35 degrees when we fired up at the slip(Cape May, NJ). I have Wolverine oil pan pads on year round so there is generally no issue with a smooth start even when the temp is in the upper 20s. This particular morning, the starboard was a bit difficult to start. I normally pump the throttles twice and then set just above idle for starting after the ignition has been on about 8 seconds. The Port fired right up with no problems and the starboard took a few tries and I had to add more throttle advance before it lighted up. Seemed to be running fine, so I figured maybe it was just the cooler weather since I hadn’t run the boat for a few weeks. We took off and ran about 10 miles to our first trolling spot. Both engines spun up fine with no smoke, just a little steam as is normal when it is cooler. We hopped around several runs like this trying to find the fish and were now about 30 miles north.

The next time when I when to throttle up, was the first sign of an issue. The starboard lagged pretty bad when the turbo should have kicked in. I think it only spun up because the port engine turbo engaged and probably pulled the starboard up after about 20 seconds. This was usual for my boat because typically the starboard turbo usually kicks in about 5 -10 seconds before the port. Still everything seemed to be running fine for a while and then I started getting dark gray smoke out the starboard exhaust. The attached video captures what it looked like. All the gauges were fine and both temp and oil pressure were reading normal. I throttled back and the smoke stopped. I tired to take off again and the starboard turbo just wouldn’t engage this time and we had a lot of black smoke.

I brought the boat to a stop, put her in neutral and raised the engine hatch. Two things immediately popped out at me. I had oil sprayed on the inside rear of the engine and I had water dripping onto the transmission.

The oil was a result of the puke bottle I had attached to the crankcase blowby hose filling with oil and the blowing out the hole in the cap where the hose loosely entered the bottle (pictures attached). This is unusual for me since there is hardly ever a drop of oil in that bottle on either engine over the course of a whole season.

The water was a result of a small hole in a raw water system pipe. It is a metal pipe that is connected to out bound side of the gear cooler by an elbow rubber hose that turns downward. The pipe runs under the turbo and then connect via another elbow rubber hose (turned upwards) to the bottom of the heat exchanger(picture attached as well). I don’t think the water leak has anything to do with the engine issue. I think it was leaking for a while since I had noticed my bilge would briefly kick on a few times during the last couple of trips. I had checked but couldn’t find any leaks. This was hidden pretty good since it was between the turbo and the transmission. Multiple calls to CUMMINS and they have yet to identify the pipe so I can order replacement.

So at this point I shut down the engine and we made the 12 mile journey back to the dock on one engine at trolling speed. Got back to the dock, took some pictures, cleaned up the oil, and then removed and patched the leaking pipe. Got up the next morning and tried to take a quick ride before haul out. The engines started fine, but the starboard wouldn’t spin up and smoked when I accelerated. I had no choice but to haul out and winterize the engines for the winter nap.

I spoke to a diesel mechanic friend who has worked on my engines in the past before he moved to Florida. He didn’t think it was the turbo, but maybe a fuel filter or an injector issue.

Aftercoolers, gear coolers and heat exchangers all removed and fully serviced per your protocols about 180 hours ago. Already have your kit with planned service before launching next month

The fuel filters get changed every spring

The injectors are all originals to the best of my knowledge.
Removed Air filter. Turbo spins free, feels tight and no binding.
No sign of water spray on the filter, only dripping down onto the transmission. Using S&B filters, clean and treat every spring. Filter is still clean inside and no oil in the air side of the turbo.

No signs of any broken clamps or leaks related to turbo, but will have to look harder when I get to the boat in a couple of weeks. Boat is docked 4 hours from home. No whistle noise or change in normal sounds other than not spinning up.

From the time I left the dock to the issue starting was about 4 hours. Engines were running continuously either cruising or trolling. I would appreciate any advice on what you think it might be and where to start.

The most recent picture of the exhaust side is shot of the engine compartment about a year ago before I cleaned up and repainted the coolant tank and the exhaust side of the turbo. The one with the fresher paint job is after a cooler service and painting in 2011, but shows the elbow better

Thanks

Steve

Topic

[siwicki]

Tony,
housing after cleaning was pretty good, but this is the corrosion spot I am concerned about

[siwicki]

more photos of the housing before cleaning

[Tony Athens]

Your cores need to be cleaned and pressure tested.. But if I was to guess, they are done..

Housings??/ No clue without pics.

Tony.

[siwicki]

After Cooler Disassembly

So I pulled the after cooler off late yesterday and cracked it open last night before it got dark. I included some photos but the bottom line was the caps on the water side were not bad at all. The top cap zinc was intact as expected with a little crude around it. The bottom cap zinc was totally shot with just a little piece resting loose in the cap. Soaked the caps in some barnacle buster and they came out nice and clean.

The core holes were all clear, but the coil wouldn’t budge. It gave it several coats of PB Blaster, and let it sit overnight. The air side had a little of the typical black sludge on the bottom side, but not much more than a single fingertip worth. About half up on the airside, there were a few dried salt specs. I went back and took a close look at the hose from the turbo to the lower side of the air side and it had similar salt specs, but a little heavier. Removed the top of the air side and the fins were a little black, but not bad. The top cap on the air side also had a few dried salt specs. Cleaner both pieces with brake cleaner and then soap, so no concerns with those pieces.

In the morning, the coil still wouldn’t budge so I took it to a local marine engine shop and they were able to easily press it out in one of their presses. The outside of the coil had a lot of crude. The inside of the housing had some similar crude but primarily at the bottom on the cooler. All of the stuff on the cooler unit came clean with some break cleaner and some soap. I attached some before and initial after photos of the coil. It is still soaking tonight in barnacle buster.

Question: I am concerned about a corrosion spot at the bottom of the cooler. I am wondering if this got so bad that this is what caused the water leak onto the outside of the coil?

Question: Since I had salt in the air side of the cooler, is it more likely it came from a leak in the cooler and all the way through from the turbo and an obviously wet filter?

More photos posted in the next reply.

Still working on getting the turbo exhaust elbow off. The bolts are not cooperating and may need to be cut off to get it free.

Thanks
Steve

[glenn111]

On my 6BTA’s when you start the engine by turning the ignition switch to the start position, high current is applied to the solenoid and it pulls-in to the full-up position. This allows fuel to flow to the fuel pump and the engine to start. When the engine starts and the ignition switch is moved to the run position, a lower current is applied to the solenoid, however enough to keep it in the full-up position. This allows fuel to continue to flow when you are in the run position. Turning the ignition switch to the off position – no current is applied and deactivates or relaxes the solenoid and the fuel is shut off. With what you mentioned earlier and looking at your pics, I would replace the whole fuel solenoid. If you manually pull the solenoid shaft up, you should feel tension trying to move it to the relaxed state.

1 user thanked author for this post.

siwicki

[siwicki]

Glenn,
Are you saying with just the ignition switch on, it should have gone to the full up position on its own?
thanks
Steve

[glenn111]

I’m not addressing the solenoid issue specifically but looking at your pics, should you replace it, make sure you measure the mounting hardware. It looks like mine with a 2 1/2″ center-to-center on the mounting screw holes. I recently changed mine. May I say, if you order a replacement from Seaboard as I did, you may receive the 3″ version. They didn’t have the smaller one, as it’s been replaced by the 3″ version. I’m sure you can find one from Cummins. I purchased mine on ebay- item ID: 231638211253.

From your pics, I would replace it. There are some great articles on this site relative to the operations of the fuel Solenoid. Basically, if all is working properly, start position (high current) of the ignition switch pulls the solenoid in. Run position (lower current) of the ignition switch holds it in the pull-position. Ignition switch off – solenoid relaxes. BTW, you can burn-up this solenoid if you keep the ignition in the start position too long…I suspect that may be why Cummins replaced them with the larger ones with the 3″ mounting holes.

[siwicki]

Fuel Solenoid

I finally got a few days off and drove up to the boat. I am still on the hardstand so this is all with the engine off. It will probably be another 3 weeks until we are in the water and able to run the boat.

Today, I started with the fuel solenoid. In doing some more research last week, I saw a video on the diesel truck version of this engine where with the ignition on, it pulled the solenoid to the full power position which made it easier for the guy to reattach and zip tie the boot. I turned the ignition on for both engines but it failed to pull either one to the full power position. When I manually pushed them to the full power position, they were held in place at full power. While the ignition was still on, I tried to see if there was any play or if I could push either one in any further, but they were both all the way up to full power. When I turned the ignition switches off, both released and extended out.

Question 1: Are the marine engines different than the truck engines in that turning on the ignition isn’t enough to pull it to the full power position? It is the same solenoid.

With the ignition in the off position, I was able to push the solenoid arm up and it traveled easily with no binding and returned to its original position when I let up on the pressure. I decided to pull the starboard (engine with issue) off and check it anyway. As I was loosening the bolts, the zip tie that was at the top of the boot either broke or was already broken on the engine side as it came off in my hand while I worked the bolts. The rubber boot was still in place.

After removing the solenoid, it traveled fully multiple times with no binding at all. After a number of times exercising the shaft, the boot came loose and the two pieces separated. Once the boot slipped off the lip, the two pieces easily separated in my hand. There was some rust on the underside of the mount and a small amount of some dry, fine, rust “dust” inside the boot and on the shaft, but it all wiped right off. Spring had the rust dust on it as well, but it also wiped off with a rag.

Cleaned up the inside components and removed all the rust from the outside housing. Repainted the solenoid exterior with primer. Also took off the mounting bracket to clean it up and prime/repaint as well. Once I re-install that, I will zip tie the arm to full power position.

Question 2: I have a question about the arm where the solenoid shaft attaches. At rest, this is currently sitting in the middle position. If I push down on it, there is some tension and it moves about half an inch downward. When I release the pressure, it comes back up to the middle position. When I pull it up to the max power position, there is no tension and I had to manually move the arm back to the middle. It felt like nothing was happening when I went from the mid-point to the max power position. Is this normal?

Some pictures attached.

Next project is to get the turbo exhaust elbow off.
Thanks
Steve

[Rob Schepis]

siwicki wrote:

I attached the engine photos from the pre-purchase survey in 2008, so I guess you are telling me both were replacements?

The unpainted compressor housings suggest that.

[siwicki]

Bought the boat in spring 2008. Third owner. Turbos are still what was on it when purchased. Tried getting service history report from Cummins first year I owned it and all they could tell me was that one injector was supposedly replaced the first year under warranty (don’t recall which engine) and nothing else on record for the Ser #s.

No real issues since purchase other than normal maintenance. Replaced throttle lever on both engines in 2009 due to one having excessive wear. Replaced starter and alternator on port engine about 4 years ago. Starter failed and alternator was operating with inconsistent voltage. Upgraded to Tony’s water pumps in spring of 2016.

Turbo must have been replaced prior to my purchase. I had always been an outboard guy and was new to diesels at the time. Had a good surveyor but he never mentioned it.

I attached the engine photos from the pre-purchase survey in 2008, so I guess you are telling me both were replacements?
thanks
Steve

[Rob Schepis]

siwicki wrote:

Didn’t try running without the filter as the filter was dry. Will add that to the list.

Salty, dirty, failing….. it takes no time to pull it off when symptoms starts.

Your image 3477 shows a replacement turbo. What is the real history here?

[Philip]

Elbows can fail in many ways including over the course of a single trip or a slowl failure and all are silent until something big happens. In either case the effects of an elbow that has been leaking eventually manifest themselves in many ways. One of those ways could have been pieces of scale, rust, metal, etc coming loose during the heat/cool cycles and causing turbo issues that can result in black smoke and excess oil etc…

Knowing the history of that stock elbow that would be my first suspect.

Please post up the pictures of the exhaust side of the turbo when you get that elbow off AND pictures of all sides/angles of the engine for us to help you with.

Phil

[siwicki]

Thanks for the link. I have read that article before and will read again and use as a guide. I will start with removing the elbow when I get up there in a couple of weeks. I have not removed the elbows in a long time. I am curious what you think could happen in the elbow to cause it to fail over the course of a single trip?

Boat only had 2 people and about half a tank of fuel. Definitely not overpropped and I was still about to turn 1800-1825 RPM before the incident.

Bottom was still clean as well when I hauled the next day.

thanks
Steve

[siwicki]

Didn’t try running without the filter as the filter was dry. Will add that to the list.

[Rob Schepis]

Did you try running the engine with the air filter removed?

[Philip]

Remember what dark smoke means… unburned fuel. Your injectors would be far down the list as a culprit. Also clogged fuel filter would not cause dark smoke as that would cause a fuel restriction NOT a fuel excess.

Starting point would be to remove that exhaust elbow and take some good pictures of that side of the turbo. Those elbows are known to fail.

This would be worth reading several times as well:

https://www.sbmar.com/featured-article/understanding-low-power-troubleshooting/

[Author]

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