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This forum contains 1,779 Topics, 10,166 Replies, and 5,292 Contributing Members.

Viewing 20 topics - 1 through 20 (of 1,779 total)
    • Cummins Marine Forum Topics
    • 2004 ZF Transmission Oil Analysis

      This topic has 13 replies, has 4 voices, and was last updated by Josh Michels 1 hour ago

      October 18, 2019 at 6:21 pm In process of purchasing a boat with these transmissions bolted up to Cummins 6CTA 8.3’s . The Oil analysis did not come back so great but the mechanics believe the fluid has never been serviced and that is why. It showed no issues of functioning when used ironically. No slippage. Let me know what you think? Is this normal with no fluid change and 635 hours or so? We changed fluids and are going to retest in 10 hours. 03 Sea Ray 390 MY At…

      Started by:  Josh Michels in: Marine Transmissions


      13 Replies
      October 20, 2019 at 6:53 pm 1) ok got it. So be on the look out and check it before it fails. Got it. Thanks for heads up. 2) Yes 480 Ce engines. 6CTA. I saw and read the article on re propping and fuel burn on the 450 versus 480 CE. Prop for 450 Curve. Got it. Once we actually get to sea trial I will be doing that. I just need to get past this initial issue or non issue with the oil samples that threw up red flags everything. I want to make sure engines internally are n…

      Last Post by:  Josh Michels posted: 1 hour ago

    • 2004 Cummins 6CTA 8.3 Oil Analysis 635 hours

      This topic has 5 replies, has 2 voices, and was last updated by Rob Schepis 1 hour ago

      October 18, 2019 at 6:16 pm Hey Guys , New to the forum but not to the automotive/marine industry. I am in the process of purchasing a boat with these Engines in it and Kubota Generator. The oil samples taken did not come back to be the best however this is some discrepancy on wether its just because its old oil and the motors were started multiple times over the last few months and not warmed up completely. So all those dry starts…….I am alittle concerned wit…

      Started by:  Josh Michels in: Cummins Marine Engines


      5 Replies
      October 20, 2019 at 5:56 pm Yes at startup, especially in colder weather. Underway once up to temperature you may see some under hard acceleration and pushing her over the hump Rob "Luck is the residue of good design."

      Last Post by:  Rob Schepis posted: 1 hour ago

    • 6BT fuel lift pump

      This topic has 1 reply, has 2 voices, and was last updated by Tony Athens 9 hours ago

      October 20, 2019 at 6:49 am Good morning. Question on the fuel lift pump on my 6BT. I have no starting issues, starts right up. Run just fun, so no issues there. I will be changing the fuel filter. Last Friday I actuated the hand pump lever on the lift pump for the heck of it. Seemed to move very free with no pressure as I would of thought it would have. Up and down like nothing was restricting the movement. My question: Is this normal or is there something wrong…

      Started by:  John Hobby in: Cummins Marine Engines


      1 Reply
      October 20, 2019 at 9:56 am The lift pump lever inside the engine rides on a CAM.. If the engine happened to stop with the “lever” on the cam, then the mechanical pump lever will feel totally limp–“NOTHING”.. Plus, if the vlever does work, than at best it’s pretty weak at best and slow to react or recover from the little bit it pumps.. An “outboard” type squeeze bulb does 3-4X the pumping with way less effort.. Tony Tony At…

      Last Post by:  Tony Athens posted: 9 hours ago

    • Rattling or Ticking Noise 6CTA (450 Diamond)

      This topic has 5 replies, has 4 voices, and was last updated by Steve 1 day ago

      October 18, 2019 at 1:17 pm My starboard engine has been running well. Actually, both have. No complaints with power, performance, or anything. However, when in the engine room today I began hearing a rattle or “ticking” sound. I looked around the engine itself and I didn’t see anything external that is loose that could be causing the rattle sound. So, naturally, I’m imagining the worst … valves. Can anyone offer a rough diagnosis from a video…

      Started by:  Steve in: Cummins Marine Engines


      5 Replies
      October 19, 2019 at 5:24 pm Thanks, guys. I’ll take a look around the engine room. I didn’t notice any soot down there recently but I’ll look more carefully. The boat was surveyed in March (when I bought it) and the exhausts were all in good shape then. But it can’t hurt to check. As to the questions by Phil: Howw many hours on the engine? 1400 What’s the service history? Pretty solid. Had the 1000 hour service done, valves adjusted aft least once. A few i…

      Last Post by:  Steve posted: 1 day ago

    • Volvo D4 which test do you trust

      This topic has 5 replies, has 2 voices, and was last updated by trnsmaster 1 day ago

      October 17, 2019 at 8:12 pm Fighting lack of power loss of rpms . Computer scan shows weak compression/ power output on cyl #1 & 4, and full output on 2&3. Mechanical compression test shows cyl 1&2 equal and cyl 3&4 equal . However 1&2 are 50 lbs less than 3&4. Which test do you trust ? If computer scan is reading wrong would that mean the computer/ecm is bad ? Thanks

      Started by:  trnsmaster in: All Other Marine Diesels


      5 Replies
      October 19, 2019 at 2:31 pm 1 )850 hrs when happened hasn’t got fixed 870 hrs now due to testing 2) previously 2800 is 20kt. 3000 is 22kt 3200 is 25kt wo@3600is30 3) can’t get over 2400 rpm now because of issue so can’t compare then to now speeds however then 1800was 12kt and 1800 now is still 12kt

      Last Post by:  trnsmaster posted: 1 day ago

    • Sherwood M71 on 6BT

      This topic has 2 replies, has 2 voices, and was last updated by John Hobby 1 day ago

      October 19, 2019 at 1:28 pm Hey guys, Again, new to this boat and the 6BT 5.9M. Great motor! 440 hours. Preparing for spring. Just winterized yesterday. Check out the pic attached. Just want to hear it before I go there. Want to replace impeller. #1 Disconnect upper and lower hose. #2 Do I un-bolt entire unit from gear train and then remove the neck transition piece to replace impeller? No typical cover plate. #3 Then lash the gears back when replacing, all done?…

      Started by:  John Hobby in: Cummins Marine Engines


      2 Replies
      October 19, 2019 at 2:01 pm Hey Bill, kinda felt the same. Jus wanted to get a handle on it. Only one engine, thank god, two would kill me! John Hobby

      Last Post by:  John Hobby posted: 1 day ago

    • Raw water impeller tool

      This topic has 4 replies, has 3 voices, and was last updated by John Hobby 1 day ago

      October 14, 2019 at 5:03 am Hi to you all. Just was told about a impeller installation tool sold by impellertool.com. Guy said it was the bomb for install. Have not priced it yet but wonder if anyone has ever ordered and used this prior to me diving in. Cummins 6BT 5.9M. Sherwood 10615 impeller, key style. Thanks, John John Hobby

      Started by:  John Hobby in: Cummins Marine Engines


      4 Replies
      October 19, 2019 at 1:45 pm Hi Tony, I just posted another question regarding the Sherwood M-71 pump. Area around it is not bad but it seems to be the type of pump that needs to be removed in order to change impeller. No cover plate. So, any help would be great. Thanks so much. John Hobby Martha’s Vineyard, MA John Hobby

      Last Post by:  John Hobby posted: 1 day ago

    • engine stalling

      This topic has 3 replies, has 4 voices, and was last updated by Tony Athens 1 day ago

      September 24, 2019 at 4:07 pm I have a 1999 6CTA on my last three trip out my engine has stalled twice at 700 rpm, I was in a no wake zone going against the current and the third time I was underway going 2000 rpm 16 kt, and it suddenly shuts off. All three times the engine restarts without a problem and doesn’t stall the the rest of my fishing trip which are 40 kt miles, I have SMX Multi stage fuel filtration system, filter where changes this year so I donR…

      Started by:  John DiFilippo in: Cummins Marine Engines


      3 Replies
      October 19, 2019 at 11:32 am John, Maybe there is some confusion here as to what EXACT engine you have.. Post a few good pics of the injection pump side of the engine, AND an engine serial number… Tony Tony Athens Seaboard Founder Go here for the latest stuff we put together and share for all to see: https://www.sbmar.com/tonys-tips/

      Last Post by:  Tony Athens posted: 1 day ago

    • QSB 6.7 After cooler Flush

      This topic has 14 replies, has 6 voices, and was last updated by Paul McInnis 1 day ago

      September 20, 2019 at 12:47 pm My engine has about 350 hours and 2 1/2 seasons of use. I want to do the Barnacle Buster flush before I haul out for the season here in the Northeast(NH Seacoast). Many good points on this forum. I will be using the groco replacement cover for the in flow. I plan to remove the exhaust hose at the heat exchanger. My question is will that hose remove easily without damage and go back easily? Attachments:You must be logged in to access attached fi…

      Started by:  Paul McInnis in: Cummins Marine Engines


      14 Replies
      October 19, 2019 at 3:25 am Thanks for clarifying. My original inquiry was about doing a flush with Barnacle Buster as I am on a mooring without any way to have a fresh water flush set up. I am now convinced that I need to service the after cooler. Is this done by just removing the end caps or does the after cooler need to be removed from the engine.? In Tony’s last reply it shows the heat exchanger what is the suggested maintenance for it?

      Last Post by:  Paul McInnis posted: 1 day ago

    • 1999 6BTA 5.9 M-3 (older style) Heat Exchanger replacement

      This topic has 6 replies, has 3 voices, and was last updated by Tony Athens 2 days ago

      October 1, 2019 at 9:08 am Was seeing signs of the heat exchanger going over the last few month (expansion tank level, engine temps creeping up) and when the alarm started sounding after running at high RPMs after about 5 minutes (temps creeping above 200F) I knew it was time to pull it. Of course it’s the starboard engine, so the heat exchanger is outboard, real PIA to take out. Soaked it (estimate about 1/3 of tubes with at least some blockage) and then pressure …

      Started by:  Paul Hoffman in: Cummins Marine Engines


      6 Replies
      October 18, 2019 at 2:47 am Paul, Do yourself a favor–Since you really do not know the internal condition of the “other seawater components”, service them all.. Seawater pump (not just the impeller), the aftercooler ( put it on the bench and remove the core & service per my protocol), gear cooler, and then your heat-x…………………..Experience has shown conclusively over the past 25 years with this cooling system des…

      Last Post by:  Tony Athens posted: 2 days ago

    • One set Batteries NOT charging

      This topic has 1 reply, has 2 voices, and was last updated by Tony Athens 2 days ago

      October 16, 2019 at 12:37 pm Here is the scenario — I have a 1998 Tiara 35 Open powered with 2 Cummins 6BTA engines (remanufactured by Cummins with 250 hours on each). I have 2 Optima batteries for start/running and 3 house batteries. The Balmar controllers are new (ARS-5) as are the two alternators (7102NKBW – Tuff Stuff) high amp output (140 amp). The house side(starboard) does a great job of charging the 3 house batteries and using my new voltmeter the Ba…

      Started by:  Paul Lagasse in: Instrumentation & Electronics


      1 Reply
      October 18, 2019 at 2:32 am For me to help ( or anyone to do this realistically) from afar, I need DC power distribution diagram showing how the engines are wired to the starting batteries and exactly how the house is connected………… You do have a common NEG ground (like 1/0 or 2/0 ga cable ) between all batteries, and the engines correct? Also, and important– You need to be sure you have the grid / air heater circuit disconnected during any…

      Last Post by:  Tony Athens posted: 2 days ago

    • head oil leak ??

      This topic has 1 reply, has 2 voices, and was last updated by Philip 2 days ago

      October 17, 2019 at 5:37 pm I have 2006 6ctas with 4,803 hrs in a 1978 42 chris craft sport fisherman.. salt water boat. My port motor seems to have an oil leak on the back of the motor at the bottom of the head. does not seem to be the valve cover or anything else. Is this a head leak or even possible. Am I missing something. It is not enough to cause and oil drop over a season compared to the starboard side. Oil consumption maybe 2 quarts over 100-150 hrs a season e…

      Started by:  Gregory in: Cummins Marine Engines


      1 Reply
      October 17, 2019 at 10:51 pm How about some good quality pictures of your engines from all sides in focus with enough resolution to zoom into things and have a look around. Include a closer up of your suspected oil leak area. Then we can hopefully help you… Phil

      Last Post by:  Philip posted: 2 days ago

    • Cummins 6BT 5.9 Gen1 Analogue Dashboard

      This topic has 1 reply, has 2 voices, and was last updated by Corey Schmidt 3 days ago

      October 17, 2019 at 11:45 am Hi there, since my boat was 11 years alone and not maintained on the hard i need to replace some bulbs on my Dashboard. ATM i am looking for the bulbs which en-light the RPM Gauge, Any idea what type of bulb is installed, i have it infront of me, but i cant identify what type it is. Happy for any help 46ft Steelyacht with 2 6BT 5.9 M 180HP First Season on the Water, for me... Attachments:You must be logged in to access attached files.

      Started by:  Oliver Heringhaus in: Instrumentation & Electronics


      1 Reply
      October 17, 2019 at 12:09 pm Those are European panels… we would have no clue… maybe someone from that neck of the woods might be able to help? Corey Schmidt | VP, Operations | Seaboard Marine, Inc.

      Last Post by:  Corey Schmidt posted: 3 days ago

    • QSC Aftercooler Part Identification

      This topic has 4 replies, has 2 voices, and was last updated by Corey Schmidt 3 days ago

      October 14, 2019 at 3:00 pm In the attached diagram, there is a ring between the two O-rings (#11). I’m not familiar with what that ring is so any help would be appreciated. My aftercoolers are on the bench now at a local shop as I could not get the cores out on my own. I just want to have all the required parts upon my reassembly of them. I do have the O-ring kits and more than enough lube from seaboard. Thanks, Tom Attachments:You must be logged in to access at…

      Started by:  Tom Bartolomei in: Cummins Marine Engines


      4 Replies
      October 17, 2019 at 9:41 am Of course we’ll need to see some clear pictures re: the pitting… We throw the silicone strips away as they are junk and always a hassle….. some people cannot live without them however… Corey Schmidt | VP, Operations | Seaboard Marine, Inc.

      Last Post by:  Corey Schmidt posted: 3 days ago

    • oil leak after raw water pump replacement

      This topic has 1 reply, has 2 voices, and was last updated by Rob Schepis 3 days ago

      October 16, 2019 at 12:41 pm Had an new SMX 1730 Seawater Pump installed on my starboard Cummins 6BTA-M3 about 6 weeks ago. When i hauled it last week, found out i had lost about one gallon of oil out of that engine, floating in the bilge. I’m not a mechanic….but was wondering if anyone who is could tell me if this install could possibly have led to the loss of oil into the bilge? Thanks. dwj

      Started by:  Dave Johnson in: Cummins Marine Engines


      1 Reply
      October 17, 2019 at 6:35 am Not much to offer without good pictures but maybe the football flange gasket was not replaced or was left out altogether? https://www.sbmar.com/product/smx-1730-seawater-pump-gasket-o-ring-kit/ Rob "Luck is the residue of good design."

      Last Post by:  Rob Schepis posted: 3 days ago

    • Wiring Size

      This topic has 6 replies, has 4 voices, and was last updated by Rob Schepis 4 days ago

      October 7, 2019 at 12:01 pm I’m going to install two (One for each engine) emergency shutoff switches in my tower. These would be used in conjunction with the redundant alarm panel I have mounted there, so I can shut the engines down quickly in an alarm situation. These would be normally closed/momentary open switches which I purchased at Seaboard. I plan on putting them in line on the”hold in” coil circuit for the fuel shutoff solenoid. They would be ene…

      Started by:  Philip Swofford in: Cummins Marine Engines


      6 Replies
      October 16, 2019 at 4:53 am Very nice and good move in pairing the 190F switches with the 160F tstats. Rob "Luck is the residue of good design."

      Last Post by:  Rob Schepis posted: 4 days ago

    • Cummins QSC 8.3 maintenance

      This topic has 8 replies, has 4 voices, and was last updated by Philip 5 days ago

      July 18, 2018 at 9:57 pm Hello everyone, this is my first time as I’m in the process of buying a new (to me) boat. I have some concerns and they may be unwarranted but I’m seeking advice and information. The boat is a 2008 and has the Cummins QSC 8.3 engines with approx 450 hours on them. I don’t know much about diesel engines but have quickly learned a lot because of this awesome site. I have an offer on the boat that is contingent on everything getti…

      Started by:  jeff vargas in: Cummins Marine Engines


      8 Replies
      October 15, 2019 at 5:54 pm 10 micron boat filter and the Fleetguard FF5488 on engine filter. The Racor can be messy, if your looking to upgrade you filter quality and capacity check out these…far superior and much easier to maintain. https://www.sbmar.com/product-category/fuel-systems/fuel-filtration-kits/ Phil

      Last Post by:  Philip posted: 5 days ago

    • Dumb move on the shifters!

      This topic has 6 replies, has 3 voices, and was last updated by Tony Athens 5 days ago

      October 3, 2019 at 3:23 pm Well, I did something stupid. I was cruising along at 2400 RPM and when I went to slow down I accidentally pulled the shifters out of gear instead moving the throttles. Seems to me that’s hard on the transmissions, but to make matters worse, without thinking, I instantly put them back into gear again (still at 2400 RPM)! I didn’t hear anything bad and there are not symptoms of anything haywire, but did I do any internal damage??? …

      Started by:  Mike Schmidt in: Cummins Marine Engines


      6 Replies
      October 15, 2019 at 11:39 am The MG506 is a really “good ol’ gear”, but is very light duty in comparason to what they’d put in off road equipment on a HP to HP basis.. A gear similar to a 506 would be rated to about 80-100HP in loader or tractor vs. 200+ HP in a boat. The “shock loads” just are not there is a boat, it’s all thru a “fluid medium”–The prop …. Tony Tony Athens Seaboard Founder Go here for th…

      Last Post by:  Tony Athens posted: 5 days ago

    • Hydraulic steering sizing

      This topic has 18 replies, has 3 voices, and was last updated by Larry aberg 5 days ago

      August 19, 2019 at 3:57 pm I I need help on figuring out how to improve the hydraulic steering system on my 55 ft powerboat. The issue is during conditions when we are running with waves and surfing down the waves the forces on the steering wheel are more than the system can exert. The wheel is solid no matter what force you apply to the wheel We generally pull the power back to slow down or end up doing lots of S turns down the coast. It doesnt take much of a swell to pu…

      Started by:  Larry aberg in: General Discussion


      18 Replies
      October 15, 2019 at 9:09 am I will get those center line dimensions this weekend. When hard to port, the port rudder is 45 + degrees but the starboard rudder is 29 +/- degrees. Hard to starboard the dimensions flop port rudder is 29 +/- and starboard rudder 45. The tie bar adjustments are max in the shortest dimension. Looks like the bar might be too long? I Larry

      Last Post by:  Larry aberg posted: 5 days ago

    • Mercury NMEA Gateway Issues

      This topic has 2 replies, has 2 voices, and was last updated by Corey Schmidt 6 days ago

      October 13, 2019 at 1:19 pm This post is meant to notify the boating community that have Q-series mid-range Cummins diesels that the latest release (~2018-2019) of the Mercury NMEA gateways have a firmware issue that prevents engine data to be relayed properly to NMEA devices (MFD’s). If you have recently purchased a gateway and are experiencing issues with the install, you will need to call Mercury support and send in the gateway to be “re-flashed”. Typi…

      Started by:  Corey Schmidt in: Instrumentation & Electronics


      2 Replies
      October 14, 2019 at 4:10 pm Yes, the gateways we have on our website are 100% compatible with the older QSC 8.3 engines and have already been re-flashed. Corey Schmidt | VP, Operations | Seaboard Marine, Inc.

      Last Post by:  Corey Schmidt posted: 6 days ago

Viewing 20 topics - 1 through 20 (of 1,779 total)