Zinc broke off in heat exchanger - 4kW Kohler

Discussion in 'Electrical Stuff' started by Little Ducky, Aug 10, 2019.

  1. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    So I was replacing some items on my generator today and when it came to change out the zinc it looks like the old one separated from the threaded cap.

    How have others gotten the old zinc out?

    I removed the heat exchanger to get a better look at the offending part. :(

    I'm going to do some internet searching before I drill it out.

    thumbnail_image1.jpg
     

    Attached Files:

  2. juggernaut1

    juggernaut1 Well-Known Member

    Apr 19, 2015
    Perth, Western Australia
    Boatless - sold Searay 38 Sundancer
    8.1’s
    Happened to me the fist time I changed mine. I pushed mine in there to dissolve away. By drilling it out you may end up drilling a hole in the internal tubes.

    I now change mine every six months and haven't had it happen again.
     
  3. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    Thanks juggernaut1 ..... I thought the same.

    I pushed it in and that's where it's going to stay.

    Since the end caps don't come off like some I've seen during my searches ...... I'm going to leave it in there and install the new zinc.

    Surprisingly during my flush of the exchanger I extracted 2 rubber fins from past broken impellers. I guess the previous owner or mechanic didn't want to go fishing to get them out. I just put a new one in today to replace an older one that looked good (all fins in place) but felt like the rubber was getting a bit stiff.

    I'm going to replace the plugs next since I have them and while I'm in position.

    I hope after toping off the coolant and burping the system .... my shutdown issue will be cured.

    We will see.
     
  4. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx 502 mag
    2005 Baja 242 islander 496
    502 mpi Bravo 1
    496 mag B1
    If you have the exchanger off I would pull the end caps and give it a good cleaning. The gaskets swell and can block the tubes with age.
     
  5. juggernaut1

    juggernaut1 Well-Known Member

    Apr 19, 2015
    Perth, Western Australia
    Boatless - sold Searay 38 Sundancer
    8.1’s
    My brother who was a commercial rock lobster fisherman was with me the first time I serviced the boat. He gave me that tip as it seems to happen from time to time.

    You will probably find you may need a hammer and punch or drift to initially get it to budge. Once it starts to move just use hand force and the punch/drift to gauge if it is going to go in all the way.
     
  6. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    Unfortunately the end caps do not come off like some I've seen. It's all copper and it looks as if the end caps are soldered on. I flushed both sides of the heat exchanger with a hose and got a bunch of rust and crap out of the coolant side.

    It's all back together and I'm going to wipe everything down and pick up my tools before heading out to get some coolant to refill.

    And pick up some pain reliever...... heheheeee... I'm going to hurt in the morning.
     
  7. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    BTW the spark plugs looked used and abused. The porcelain actually looked discolored compared to the new ones..... it must get hot where they are located.

    They were Champion replaced with the alternative NGK per the manual.
     
  8. Strecker25

    Strecker25 Well-Known Member PLATINUM Sponsor

    Nov 20, 2014
    Rochester, NY
    2002 410DA
    Caterpillar 350HP 3126
    They go neglected on our boats because the service is so damn painful. I pushed ours in the first change as well
     
    Little Ducky likes this.
  9. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    I've taken a few Aleve to try to word off the stiffness in the AM. :)

    BTW the dam anti slip on the floor has to be like 600 grit sand paper..... my knees and one toe got rashed during my generator play today. ugh. But if everything works as it should ...... it's well worth a few nicks and scratches. ;)
     
  10. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    This morning topped it off with 50/50 coolant and it started up like a champ.

    It's been running now for about 10 minutes so we will see if my shut down condition returns.

    I just loaded it up by turning on the AC. Took it like a champ..... just a single blip and then rock steady at 120V. :)

    When I started it up you would have thought I was having a foam party..... I guess I used a bit more dish washing liquid than I thought when I replaced the rubber impeller. Heheheee...:D
     
  11. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    My jubilation was pre-mature.

    It shut down after about 20 minutes. :mad:

    I'm going to let it cool and then check for air in the cooling system again.

    More trouble shooting ahead.
     
  12. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx 502 mag
    2005 Baja 242 islander 496
    502 mpi Bravo 1
    496 mag B1
    You forgot to take the 20 year old HE apart for a good cleaning.

    Overheat shutdown right ? Them things don't have an infinite lifespan.

    Good luck with it.
     
  13. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    It doesn't come apart. If it did I would have done it.

    But I did flush through both sides when I had it off the generator until clear water ran out...... vs the rusty mess that came out.
     
  14. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx 502 mag
    2005 Baja 242 islander 496
    502 mpi Bravo 1
    496 mag B1
    I can clearly see an end cap in your pic, how did they attach it ?
     
  15. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    It's soldered on and then it looks powder coated. There's no center screw and gasket like some Heat Exchangers I've seen while searching.
     
  16. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    BTW I stared it back up and ran w/o the coolant cap in place and added more coolant while the air was being forced out of the system. I was very surprised at how much more coolant it took once all the air bubbles stopped.

    But it then turned off again after about 15-20 minutes.

    It's not over heating ...... if it was the coolant would have been boiling out since the coolant cap was off.

    So how often does the coolant temp sensor or exhaust temp sensors go bad?

    Can I disconnect and run the generator to take them out of the auto shut down equation or do I need to do something else to trick the system?
     
    Last edited: Aug 11, 2019
  17. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    Saga continues:

    I removed the wires on the exhaust temp sensors because they were very accessable and while doing so one crumbled. I taped up the ends and started the generator back up.

    Could this be it? Faulty broken sensor........ o_O

    Time will tell. Fingers crossed.
     
  18. Little Ducky

    Little Ducky Well-Known Member

    Jun 5, 2017
    Dickson, TN / Chattanooga, TN
    1998 290 Sundancer
    Twin EFI 5.0L w/Alphas
    Kohler 4kW
    Dam. Turned off again.

    I'm going to order up 2 replacement exhaust temp sensors since one is broke and then continue my quest at a later date once installed.

    Enough tinkering for now.
     
  19. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx 502 mag
    2005 Baja 242 islander 496
    502 mpi Bravo 1
    496 mag B1
    You could ohm test them to see if they work.
     
    Little Ducky likes this.
  20. JVM225

    JVM225 Well-Known Member

    Apr 8, 2008
    Farmingdale, NY
    2002 410 Sundancer, Monaco Edition.
    3126 Cats.
    That’s a common occurrence with the pencil zincs and caps in the aftercoolers of my Cat 3126”s. Almost routine. I have a kit that I bring down to the boat when it’s time to change the zincs.
    Included in the kit is a reverse bit and EZ OUT. That’s what I use to get the ones that are broken like that out.
    To try to prevent it from happening again, or at least lessen the chances, get a plumbing pipe wire brush from Home Depot and clean the area where the pencil zinc wants to mate itself to the heat exchanger really well
     
    Little Ducky likes this.

Share This Page

Show Sidebar