Page 1 of 2 12 LastLast
Results 1 to 20 of 39

Thread: Can't idle off dock

  1. #1

    Default Can't idle off dock

    I use to have a 305 in my Seasport, now I have a 350 (carb), installed new a few summers ago. Neither engine has ever been able to "cleaning" get off the dock without stalling, the new motor is worse. This goes for leaving a cove in the morning, pulling anchor, and trying to take off without it stalling. Once I'm clearly able to crank it open outside the bay/cove, I can clean it out and she runs like a top all day, even shutting it on and off. It's the initial first day cold start, of a two day weekend.

    (I basicly use the kicker to leave the habor, just easier than stopping/stalling over and over around the dock.)

    Someone suggested turning up the idle (made no difference) another idea was "open the dog house" to let it get more air, haven't tried that yet.
    (running the blower??? didn't do much either)

    -Thanks for your thoughts

  2. #2
    Moderator bkmail's Avatar
    Join Date
    Apr 2006
    Location
    Palmer, AK.
    Posts
    4,112

    Default

    Sounds like it isn't warming up properly. Might it be as simple as changing the thermostat?

    Is the choke working correctly?
    BK

  3. #3
    New member
    Join Date
    Jan 2010
    Location
    Eagle River
    Posts
    2,022

    Default

    Is the choke working correctly?
    BK
    That is the first thing I would check.

    The second thing I would check for is a submerged float in the carb bowl, a common ailment on a Quadrajet which are common on GM small blocks, but mayhap someone installed a Holley or Edelbrock. If a Quadrajet one can see the top of the float by looking down the slot next to the post that the spark arrestor/air filter mounts over/is retained by, if you see fuel on top of the float it will need to be replaced/carb overhaul. A heavy/saturated float will not close the needle in the seat and fuel will overflow into the bowl causing a flood condition, a condition much easier for a hot or warm engine to deal with than a stone cold one.

  4. #4
    Member
    Join Date
    Apr 2006
    Location
    Anchorage
    Posts
    1,762

    Default

    If both Eng's do the same thine could it be the BOAT gas tank, line or something like that or voltage to the distribiuor just an Idea I don't know just thing of some thing that is common
    SID

  5. #5

    Default

    Warm-up; Warming it up is critical, actually warmed it up "too long" once (buddy ran back up the dock to use the restroom...) the motor loaded up and never cleaned out all weekend. Stayed loaded, probably because we stayed in the harbor and never ran it out for any length of time, just idled around the harbor trolling for Silvers (Seward, end of season...)

    It sure feels like the choke doesn't "let go" or something "sticks" until you open it up on step outside the harbor. In Homer, I idle from the ramp to the fuel dock, even by the time I get to the fuel dock, it still stalls because I haven't been able to get it up on step yet to clean it out. YES, it blubbers black smoke into the water warming up!

    My mechanic said it should warm up and be able to get off the dock. This is not the case -ever.

    I'm lost. Carb tune next???

  6. #6
    New member
    Join Date
    Jan 2010
    Location
    Eagle River
    Posts
    2,022

    Default

    Quote Originally Posted by Myers View Post
    Warm-up; Warming it up is critical, actually warmed it up "too long" once (buddy ran back up the dock to use the restroom...) the motor loaded up and never cleaned out all weekend. Stayed loaded, probably because we stayed in the harbor and never ran it out for any length of time, just idled around the harbor trolling for Silvers (Seward, end of season...)

    It sure feels like the choke doesn't "let go" or something "sticks" until you open it up on step outside the harbor. In Homer, I idle from the ramp to the fuel dock, even by the time I get to the fuel dock, it still stalls because I haven't been able to get it up on step yet to clean it out. YES, it blubbers black smoke into the water warming up!

    My mechanic said it should warm up and be able to get off the dock. This is not the case -ever.

    I'm lost. Carb tune next???
    Yes it sounds very much like a carb issue. As I said prior it is likely a choke issue-could be the choke pull-off diaphragm(if equipped) or the heated coil pull-off(it will have one style or the other), and/or the float is low in the bowl allowing unmetered fuel into the engine. One thing for certain based on your description is that is it far too rich.

    Should be a piece of cake to figure out, let me know if you need help, I have a lot of time and a ton of experience.

  7. #7
    Member Bullelkklr's Avatar
    Join Date
    Apr 2006
    Location
    Anchorage Alaska
    Posts
    4,833

    Default

    It almost sounds like the carb is staying choked. I assume you have tried to give it a quick rap of the throttle to bring it off fast idle and set the choke back?

  8. #8
    Member
    Join Date
    Apr 2006
    Location
    Anchorage
    Posts
    3,246

    Default

    I'm going to agree with SID, it makes no sense two difference engine and the same problem!!! There must be some common item that causing the problem and have you try a new mechanic.

    Did you pull parts off the old engine and put them on the new one?

  9. #9
    New member
    Join Date
    Jan 2010
    Location
    Eagle River
    Posts
    2,022

    Default

    Quote Originally Posted by MacGyver View Post
    I'm going to agree with SID, it makes no sense two difference engine and the same problem!!! There must be some common item that causing the problem and have you try a new mechanic.

    Did you pull parts off the old engine and put them on the new one?
    It makes perfect sense if the bolt on parts were transfered from one engine to the other, as is typical, and over time the problem has grown worse.

  10. #10

    Default

    Quote Originally Posted by .338WM View Post
    It makes perfect sense if the bolt on parts were transfered from one engine to the other, as is typical, and over time the problem has grown worse.
    .338, I'll take you up on the offer come spring. I rev the crap out of it trying to clean/unstick whatever at the dock. When I get to open water and bang it into gear as fast as I can to keep it from stalling, it kind of wants to die or bark all at once, then if she barks it takes off and cleans out.

    I didn't do the motor switch, carb was replaced along with motor.

    Like I said earlier, I just use the kicker out of harbors, I pretty much just resided to the thought that it was a "350 blubbering hot-rod type engine" that was going to be the way it is forever.

    It would really take the stress away to get this fixed, as I have become a ninja master when it comes to navigating harbors in any situation, wind, traffic, no engine, etc...

  11. #11
    New member
    Join Date
    Jan 2010
    Location
    Eagle River
    Posts
    2,022

    Default

    Has it ever run properly since the new engine was installed?

  12. #12
    Member SockeyeOne's Avatar
    Join Date
    Oct 2013
    Location
    Adirondack Mountains
    Posts
    172

    Default

    What do your plugs look like?

    I agree choke or floats are a good place to look first.

    Also, what kind of spark are you getting? Could the ignition circuit be breaking down? Electronic or points? Resistor or non-resistor plugs? How are those ignition wires, rotor, cap, coil, etc.?

  13. #13
    New member
    Join Date
    Jan 2010
    Location
    Eagle River
    Posts
    2,022

    Default

    Quote Originally Posted by SockeyeOne View Post
    What do your plugs look like?

    I agree choke or floats are a good place to look first.

    Also, what kind of spark are you getting? Could the ignition circuit be breaking down? Electronic or points? Resistor or non-resistor plugs? How are those ignition wires, rotor, cap, coil, etc.?
    From what I understand in the OP is that after it is out of the harbor and going it runs OK. If the ignition was breaking down it would be even more apparent under a heavy load such as moving the boat on step. The greater the load, the more noticable a defect in the ignition.

    Hopefully, all of those ignition components were new when the engine was installed.

  14. #14
    Moderator bkmail's Avatar
    Join Date
    Apr 2006
    Location
    Palmer, AK.
    Posts
    4,112

    Default

    Myers,
    Is this engine sucking up cold ocean water and cooling the motor by circulating it through the block?
    OR, does it have a heat exchanger that prevents seawater from circulating through the block?

    BK

  15. #15
    Member SockeyeOne's Avatar
    Join Date
    Oct 2013
    Location
    Adirondack Mountains
    Posts
    172

    Default

    Quote Originally Posted by .338WM View Post
    From what I understand in the OP is that after it is out of the harbor and going it runs OK. If the ignition was breaking down it would be even more apparent under a heavy load such as moving the boat on step. The greater the load, the more noticable a defect in the ignition.

    Hopefully, all of those ignition components were new when the engine was installed.
    Well, the ignition situation came to mind because I have two older flat tappet 305's in my boat. They had the old points and condensor type ignition until this past spring. (1700 hrs on the motors.) I was having trouble at idle first on my Stbd, then eventually on my Port. What would happen was, they would start and idle then die immediately upon engaging the gear. I went thru the Q-jets thinking it was a carb issue, and while I was able to get the carbs dialed in nice, it didn't help my situation much. I was still stalling under load at idle on the Port. The Stbd was I believe a combination of issues.

    So between gear wobble on the shaft from wear, worn down points, and older wiring from the coil to the dizzy I was totally losing spark at idle. Putting it into gear was enough to stall it. I dropped in two Mallory YLM distributors and added new wires and plugs. After timing it, the problem is gone.

    On the topic of new ignition components, I too hope they got swapped out during the repower, but there is really no way of knowing without the OP confirming. Also if the resistance value is too high from bad or improper wires or the wrong type of spark plugs that too could cause a low spark/no spark situation. Anyone put a timing light on it yet to ensure its set right? 8* BTDC is correct for these marine SBC's with carbs. For some reason a lot of them get set to 5* BTDC, which is not correct.

    Its curious though that this problem was present before and after the repower. Leading me to think that some component that was swapped over from the old block is the problem. Was this a long block swap, short block swap with the old heads, or something else? I suppose knowing what was brought over from the old set-up would help isolate the issue.

    I agree the carb is probably the most likely. Perhaps a known good one could be swapped onto the problem engine for testing. That would surely help make the process of diagnosing the carb a bit faster. If it runs well on a known good carb, I guess the best thing to do would be have the bad one rebuilt while its already off. RaceKrafters in Lancaster PA is the best place I know of to have a Q-jet rebuilt. Just mail it to them. Lots of shops who say they are good with carbs are not, and its more than a bit of a dying talent. An Edelbrock 1409 swap is also an option, but frankly the Q-jet when properly tuned is a better unit IMO. Cost of a 1409 swap and a quality Q-jet rebuild are about the same at regular marine shop rates.

  16. #16

    Default

    More info:
    Original motor was a 305 Chevy, New one is a Mercruiser 350, heat exchange, Volvo 280 out drive. Everything was changed.

    When I first took it out and the entire first summer, I spent a few trips on Big Lake dealing with a strange "electrical Type" stall while running on step. Basically, the motor would "blink" off for a millisecond! It would do this maybe a dozen times an hour traveling out to the fishing grounds. This "hiccup" was resolved, but never anyone actually "knowing" what it really was. I actually had a mechanic from the shop come out on a run on Big Lake to diagnosis. WHAT WAS ACTUALLY DONE: Every single bloody wire, electrical item, you name it was changed! The shop that did the motor swap was awesome, they pulled stuff off until it went away completely, never to hiccup again!

    But, the idle issue has never been resolved and I was looking for to it being resolved after spending 9k on a new motor. Which by the way, gets worse gas mileage, but has more power, pulls stronger getting on step and during stormy seas. I do love the power increase, feels way better.

    So I can run this on the garden hose forever, they can run it in a barrel at the shop for an hour (which has been done) If I can get it into open water and bang it into gear and get it rolling before it pukes, she's golden.

    If I had one of you guys with me I bet you'd figure it out instantly, it can't be that serious if it runs fantastic all weekend afterwards. HECK, I even do the "wait in the harbor idle line waiting to touch the dock in Whittier" on Sundays when it's crowded! It idles great then (thank goodness).

  17. #17
    Member SockeyeOne's Avatar
    Join Date
    Oct 2013
    Location
    Adirondack Mountains
    Posts
    172

    Default

    So its loading up. Really back to floats and choke here, possibly metering rods. See if you can borrow another Q-jet that is known good.

  18. #18
    Member
    Join Date
    Aug 2007
    Location
    Eureka MT
    Posts
    3,048

    Default

    Could be the float but probably not as it would run bad at idle always, not just when warming up. Sounds like either the choke pull off diaphram is broke or it's not adjusted correctly ( some Q jets have 2 pull offs). When started cold and idling the choke plate should open approximately 1/4" measured from the air horn to the top of the choke plate. 1/4" drill bit makes a nice guage. If it doesn't open at all the choke pull off diaphram is probably broken. If it opens but less than 1/4" it needs adjusted by bending the rod that goes from the choke pull off to the choke plate.

  19. #19

    Default

    Climbed into boat last night just to verify; yes, of course the carb is new. Wish I could fire it up and test this stuff, you guys have been extremely helpful and I haven't tried any of these tips yet. I'm feeling confident about where to start come spring time.

  20. #20
    New member
    Join Date
    Jan 2010
    Location
    Eagle River
    Posts
    2,022

    Default

    What kind of car, Holley, Rochester, Carter, Edelbrock? Is it a "new" rebuild, or is it NEW? Nearly every single "new" rebuild I have installed I had to take back off and overhaul regardless of what name was on the box, there is also the possibility that it is not the correct carb- too many CFM, too large of jets.

    Of course there is a possibility that it is not carb at all, but your description sure leads me to think it is related. Another thought, was the fuel pump replaced, and is it mechanical-mounted on the engine block, or is it electric-could be in the tank or external someplace?

Page 1 of 2 12 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •