• Creator
    Topic
  • #33582

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    I’ve seen discussion of little heat pucks that can be used as additional overheat alarms.

    My northern light generator started to shut down the second the shutdown bypass/preheat switch was released. Investigation showed a bad temp switch which I am replacing but it also showed my exhaust temp switches wires were. It and corroded.

    It’s brutal access and the exhaust switch wires go into a harness that’s going to unleash more demons if I cut into it. I’m thinking tobuy one of those exhaust pucks and just wire it to an alarm and forget about replacing the northern lights switch.

    Who makes themand whee can I buy them?

Viewing 20 replies - 1 through 20 (of 20 total)
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    Replies
  • #34150

    Rob Schepis
    Forum Moderator
    Vessel Name: Tenacious
    Engines: 6BTA 5.9 330's - "Seaboard Style"
    Location: Long Island, NY
    Country: USA

    Cut some test studs and JB Weld them to a metal test piece.

    #34131

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    JB Weld?

    Can I JB weld a pair of studs on? It’s rated to 500F…..

    #34121

    Rob Schepis
    Forum Moderator
    Vessel Name: Tenacious
    Engines: 6BTA 5.9 330's - "Seaboard Style"
    Location: Long Island, NY
    Country: USA

    Studs for Temp Switch

    Larry, zoom in on this one.

    #34120

    Rob Schepis
    Forum Moderator
    Vessel Name: Tenacious
    Engines: 6BTA 5.9 330's - "Seaboard Style"
    Location: Long Island, NY
    Country: USA

    Those studs are welded on

    #34119

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    Idiot ^2

    I just reread the entire thread, and blew up Tony’s picture of thr heat puck installation. If he had used a good camera I could answer my own question 🙂

    Somehow the heat puck is bolted to the exhaust elbow by studs. What holds the studs on the elbow!

    #34118

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    I am a

    I.D.I.O.T.!!!! It has 2 screw holes on the ears but I can Mcgyver a hose clamp solution somehow or other.

    And yes I am alarmed with a very good raw water flow alarm and a very sensitive Borel heat sensor which has to be a ways back on the exhaust tube so as to not generate constant false alarms. When you pull back a QSM from cruise after a 5 hr steam and reduce the water flow to a trickle the exhaust tube will hit 210-220 on top for quite a while till things cool down.

    I got the Borel far enough back on the tube and down not to generate false alarms but want to get a sensor on the elbow also under more independent alarms are better theory. That sensor will go with its own red LED. I guess I’ve got to play around with a heat gun some day after a long steam and see where on the elbow is a good spot to put the sensor.

    #34117

    Rob Schepis
    Forum Moderator
    Vessel Name: Tenacious
    Engines: 6BTA 5.9 330's - "Seaboard Style"
    Location: Long Island, NY
    Country: USA

    Adhesive to install the temp switches? Not sure about that … might effect the performance of the switch, should be metal to metal contact, the adhesive may act as an insulator. Does the switch have ears on it? Can you secure it to the genset mixer using stainless band clamps?

    On the QSM am I seeing a Borel sensor band and a raw water flow switch?

    #34074

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    How to attach sensors to elbows?

    Got the two sensors and the alarm yesterday. What’s the right adhesive to use to attach one to a stainless QSM elbow and the second to the cast Northern Lights Elbow.

    Also, in the case of the QSM elbow, where should I glue it, top or bottom, front or back?

    #33657

    Tony Athens
    Moderator
    Vessel Name: Local Banks
    Engines: QSB 6.7 550 HP
    Location: Oxnard, CA
    Country: USA

    From what I have seen, NL makes very nice cast SS mixers that are very inexpensive, in fact they are dirt cheap compared to what I could make… To not replace it seems silly to me.. Call these guys–they stock all of them.. In fact anything NL, this is where you want to go…

    AAA Marine, Ventura, Ca………… http://www.aaamarineventura.com/ ………………………… Ask for Erith..

    Tony

    #33656

    Bill Desmarais
    Moderator
    Vessel Name: Extremist
    Engines: Cummins 6BTA 370
    Location: Portsmouth, NH
    Country: United States

    Larry,
    I had the same NL 753 generator in my former 1996 Blackfin.
    I replaced the exhaust mixer and recall it was metal.
    The old one had rusted up pretty good.

    #33643

    Rob Schepis
    Forum Moderator
    Vessel Name: Tenacious
    Engines: 6BTA 5.9 330's - "Seaboard Style"
    Location: Long Island, NY
    Country: USA

    The elbow is metal for sure —- either cast iron or 316 SS

    That section of wire appears to have been chafed through, and then the conductors corroded, shorted, or both…

    #33623

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    ain’t pretty but maybe this is metal?

    1st shows the puck, 2nd misses it but shows the elbow better, 3rd is the piece of wire that I cut out thatsas frayed and corroded through.

    #33622

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    Northern Lights M753K

    And yes, I sure wish I had studied the parts diagrams as well as the wiring diagrams before I started chasing this problem.

    #33621

    Rob Schepis
    Forum Moderator
    Vessel Name: Tenacious
    Engines: 6BTA 5.9 330's - "Seaboard Style"
    Location: Long Island, NY
    Country: USA

    Wow, that bad, I guess (or I hope) the “service side” has the better access than the non-service side. Not that there’s anything mechanical or electrical in a boat that is “service-free”!

    Try to take some pics when you get in there (wishful thinking, I know..)

    What model NL unit is it? Especially in limited access situation it’s best to study pictures & diagrams BEFORE you get into it so you know exactly what you are looking at……

    #33620

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    Yes on elbow

    Everything in the genset is coated in white paint, it very well may have been a metal exhaust,imgoing to have to crawl back in there to find out, ugh…

    #33619

    Rob Schepis
    Forum Moderator
    Vessel Name: Tenacious
    Engines: 6BTA 5.9 330's - "Seaboard Style"
    Location: Long Island, NY
    Country: USA

    There was a glue on puck there already so maybe there is a metal flange it attached to.

    Where, on the genset exhaust elbow?

    #33618

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    I’m still ordering 2

    One is going on my QSM exhaust elbow as yetanother independent insurance policy and I’ll figure out something on the Northern Lights. There was a glue on puck there already so maybe there is a metal flange it attached to. As I said, access is horrible and I didn’t really examine the exhaust tube where it was attached. Definitely fiberglass tube once it’s out from behind the genset where I was hoping to attach it.

    #33607

    Tony Athens
    Moderator
    Vessel Name: Local Banks
    Engines: QSB 6.7 550 HP
    Location: Oxnard, CA
    Country: USA

    Our heat sensors are NOT designed nor do I believe they will work well on a FRP tube.. The switch is N.O. and closes at 165F.. FRP is not a good / quick transfer medium of heat changes.

    Tony

    #33604

    Larry Backman
    Participant
    Vessel Name: Skipjack
    Engines: QSM 670
    Location: Cape Cod, MA
    Country: US

    Thanks Rob

    Exactly what I was referring too. I just ordered a pair. Any advice on how to best stick it to a fiberglass exhaust tube?

    #33583

    Rob Schepis
    Forum Moderator
    Vessel Name: Tenacious
    Engines: 6BTA 5.9 330's - "Seaboard Style"
    Location: Long Island, NY
    Country: USA
Viewing 20 replies - 1 through 20 (of 20 total)

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