Troubleshooting is a process, not guessing

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  • ndutton
    Afourian MVP
    • May 2009
    • 9601

    Troubleshooting is a process, not guessing

    I've owned Kalina for 12 years now with no significant engine repairs and no indication any significant repairs were ever made by the PO. The engine has always started within a second or less of cranking regardless of layoff time. I've become so confident in it I open the raw water intake thru-hull before starting knowing there's no risk of overfilling the waterlift.

    Until yesterday . . . .

    I went through the normal routine: blower on, fuel valve on, engine start battery on, intake thru-hull open, sink drain thru-hull open (Catalina 30 owners know why), check the oil, sniff the bilge. All good. I pulled the choke on full, cracked the throttle open, ignition switch on and push the start button. She cranked, popped and coughed but no joy. Oh-oh, now it's finally happened to me. Better close the thru-hull before I make things worse and of course left the ignition switch on without the engine running. After the 10 second delay I built in to my EWDS installation the buzzer lit off so at least I was reminded*. BTW, during the start attempt there were no EWDS faults which indicated sufficient fuel pressure and sufficient coil input voltage.

    I tried starting a few more times, jockeying the throttle and choke but still all I got was popping and coughing. Okay, at this point, what to do? It could be this, could be that, fuel or electrical, who knows? Well, I had a little information to start with. It was popping and coughing suggesting I was getting spark. Probably the best thought I had was, "what was the last thing you did to the engine?"

    Several weeks ago Tom Thatcher and I took Kalina over to Catalina, an abbreviated trip due to a severe weather forecast that came up overnight (we decided discretion was the better part of valor and got the Hell out of Dodge before the weather hit). We motored all the way over, saw a gray whale and a juvenile humpback (very cool) but also experienced a couple of RPM blips. After returning I removed the carburetor for a thorough cleaning, fuel filter replacement and examination of the filter contents. I found a speck inside the carb but nothing else.

    I reinstalled the carb with the idle mixture screw the prescribed 1½ turns off the seat and she started easily, dialed in the mixture, ran it for a while and called it good. That was the last thing done, idle mix adjustment. This episode was the first time I'd started it, or tried to, since then. With all the combined information I screwed the idle mix screw in to its seat counting the turns. Oh-oh, 2½ turns. That ain't right, it's always been happy at about 1¼ turns. I reset to the default 1½ turns and she fired easily. Cool. I shut her down immediately because the thru-hull was still closed as a precaution. After opening it I restarted and carefully dialed in the mixture screw, wound up at the normal 1¼ turns. I ran her in gear at the dock for ½ hour, smooth as silk.

    The lengthy story (sorry) is intended as an example of gathering up as much information as possible before tearing off on a guessing expedition.

    *About the EWDS
    With the accidental ignition on-engine off episode the EWDS gave me the audible alarm combined with oil pressure, fuel pressure and raw water flow indicator lights. Perfect.
    Last edited by ndutton; 06-30-2017, 11:30 PM.
    Neil
    1977 Catalina 30
    San Pedro, California
    prior boats 1987 Westsail 32, 1970 Catalina 22
    Had my hands in a few others
  • Whippet
    Afourian MVP
    • May 2012
    • 272

    #2
    good job

    for a moment there I thought I was in an alternative universe. Neil have engine trouble? not possible.

    But it didnt take long for the MVP to figure it out.

    I didnt realize she was that sensitive to the mixture setting. Now i know to put it on check-list.

    thanks
    Steve
    Etobicoke YC, C&C27
    A4 #204381, 1980

    Comment

    • JOHN COOKSON
      Afourian MVP, Professor Emeritus
      • Nov 2008
      • 3500

      #3
      Neil
      I like the title of your post. Trouble shooting is a process. Guessing is well....guessing.
      I notice a lot of times in the forum we have folks that report that they have tried this and that before they any diagnostic information. (Spark and fuel in the cylinders, compression, choke and timing set correctly)
      I over do it at times. I'll start the engine before a procedure to be sure I have a running engine. Then if the engine doesn't work correctly I know the cause.

      TRUE GRIT

      Comment

      • ndutton
        Afourian MVP
        • May 2009
        • 9601

        #4
        Infrequent member Silver Fox realized this seven years ago
        Last edited by ndutton; 05-15-2019, 07:31 AM.
        Neil
        1977 Catalina 30
        San Pedro, California
        prior boats 1987 Westsail 32, 1970 Catalina 22
        Had my hands in a few others

        Comment

        • thatch
          Afourian MVP
          • Dec 2009
          • 1080

          #5
          To elaborate a little on the Catalina trip, despite having to "motor" most of the way, we were able to have several hours of good conversation, without going "hoarse", thanks to his quiet running A4. Try that with a diesel. Like Neil, I have found that my idle mixture screw likes to be set at 1-1/4 turns out, this holds true with all three of my carbs. I'm a "non PCV, factory timing, non adjustable main jet" kind of a guy that has had very good success at maintaining a sweet running A4. Recently while going through the introduction phase with some new "dock neighbors", the conversation turned to what kinds of motors we had. His is a Yanmar diesel. When I told him that I had an A4, his response was, "those are those quiet, smooth running little engines" to which I replied, "Yea, they're kind of a cult motor". Thank's again to Neil for his invite to his really special Catalina 30 "Kalina".
          Tom Thatcher

          Comment

          • alcodiesel
            Senior Member
            • Oct 2015
            • 293

            #6
            Cult or not?

            Tom wrote: "Yea, they're kind of a cult motor"- I concur. I think mine actually purrs at certain RPMs.
            Bill McLean
            '76 Ericson 27
            :valhalla:
            Norfolk, VA

            Comment

            • capnward
              Afourian MVP
              • Aug 2012
              • 335

              #7
              proud cult member

              "Cult motor", that's perfect. Except I think of us more as internal combustion orthodox. The church of purring engines. Amen.
              What is factory timing? Does that just mean points and condenser instead of electronic ignition? I remember playing with points, condensers, point filing, point gap measuring and adjusting, timing strobe light, dwellometer, etc. when I had a 1972 Datsun pickup for 17 years. It was a great truck, but I don't miss tinkering with dwell every few months. My EI from Indigo has been install and forget.
              The Moyer manual says the idle screw should be set 1-1/2 turns out. Don Moyer told me in 2011 that 1 turn is actually enough. That's how mine is currently set, but rpm occasionally decrease for a few seconds until warmed up, if kept at idle. She starts right up, but 5 minutes later the rpm begin to drop. It can get well below 800 rpm for about twenty seconds until it seems to catch itself and accelerate a bit, but then a minute later drops again. Not enough to shut down, though. If I throttle up it doesn't help much, because the problem reoccurs when I throttle back down. It seems to push through a series of fuel obstructions. Perhaps water evaporating. After 15 minutes of running it's fine, and stays that way as long as it's warm. I don't know that the idle adjustment is the cause. We'll see. Maybe the idle ports need clearing, but I did that 2 months and 20 engine hours ago, with the rest of the carb.
              Thanks Neil, for demonstrating the proper way to go about troubleshooting. We don't learn much by guessing, even if we guess right. The Lesson: Always keep in mind the most recent change to your settings.

              Comment

              • roadnsky
                Afourian MVP
                • Dec 2008
                • 3101

                #8
                My slip neighbor (Diesel) still thinks my bilge pump is running when I start my engine.
                -Jerry

                'Lone Ranger'
                sigpic
                1978 RANGER 30

                Comment

                • thatch
                  Afourian MVP
                  • Dec 2009
                  • 1080

                  #9
                  Timing

                  Capnward, Assumming that you have access to the flywheel end of the engine, and if you still have a timing light, setting the timing to factory specs is pretty easy. I normally paint the important timing marks, rolled pin in this case, with a little white fingernail polish so that it will really "pop" in the strobe light. With the distributor loostened a little, and the engine running, rotate it a little in the appropriate direction until the the pin is straight up, in the light. If the idle drops, this probably means that your ignition was advanced to a certain degree. I realise that "power timing" is popular, but along with that practice comes more blow-by.
                  Tom

                  Comment

                  • edwardc
                    Afourian MVP
                    • Aug 2009
                    • 2491

                    #10
                    Originally posted by roadnsky View Post
                    My slip neighbor (Diesel) still thinks my bilge pump is running when I start my engine.
                    My bilge blower is louder than my engine!
                    @(^.^)@ Ed
                    1977 Pearson P-323 "Dolce Vita"
                    with rebuilt Atomic-4

                    sigpic

                    Comment

                    • JOHN COOKSON
                      Afourian MVP, Professor Emeritus
                      • Nov 2008
                      • 3500

                      #11
                      CPTNWARD
                      Do you have a fuel pressure gauge?

                      TRUE GRIT

                      Comment

                      • capnward
                        Afourian MVP
                        • Aug 2012
                        • 335

                        #12
                        Good point, John. Yes I do. Next time I will check it when this idle drop happens.

                        Comment

                        • Roadking Larry
                          Senior Member
                          • Mar 2014
                          • 51

                          #13
                          Originally posted by edwardc View Post
                          My bilge blower is louder than my engine!
                          Mine also. I do have a lazerette hatch that will rattle in an annoying way if I'm running at hull speed though, just change sides and sit on that hatch.

                          Comment

                          • alcodiesel
                            Senior Member
                            • Oct 2015
                            • 293

                            #14
                            The Zen of repair

                            Roadking, that's my kind of fix!: " just change sides and sit on that hatch."
                            Bill McLean
                            '76 Ericson 27
                            :valhalla:
                            Norfolk, VA

                            Comment

                            • JOHN COOKSON
                              Afourian MVP, Professor Emeritus
                              • Nov 2008
                              • 3500

                              #15
                              Originally posted by capnward View Post
                              That's how mine is currently set, but rpm occasionally decrease for a few seconds until warmed up, if kept at idle. She starts right up, but 5 minutes later the rpm begin to drop. It can get well below 800 rpm for about twenty seconds until it seems to catch itself and accelerate a bit, but then a minute later drops again. Not enough to shut down, though. If I throttle up it doesn't help much, because the problem reoccurs when I throttle back down. It seems to push through a series of fuel obstructions. Perhaps water evaporating. After 15 minutes of running it's fine, and stays that way as long as it's warm. I don't know that the idle adjustment is the cause. We'll see. Maybe the idle ports need clearing, but I did that 2 months and 20 engine hours ago, with the rest of the carb.
                              CAPNWARD
                              Why not start a thread on this problem?
                              The best I can come up with other than the carburetor is a sticky advance. It is a long shot though.

                              TRUE GRIT

                              Comment

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