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Need blown engine advice

Discussion in 'Boats, Blinds, & Gadgets Forum' started by muddywater, Aug 21, 2017.

  1. muddywater

    muddywater New Member

    Messages:
    21
    Joined:
    Aug 29, 2014
    Location:
    LA
    I burned up my engine this weekend. It was pumping perfectly when we went out, but coming in I noticed it was not pumping and dropped off plane, but it overheated and killed pretty much instantly with the dreaded smoking and sizzling sounds so I noticed too late. Although I have not had time to check compression etc, I am guessing that I am looking at a total rebuild or new engine.

    My problem is the lack of any new engines in the same power/weight class and I am not sure whether it is worth rebuilding the old one especially since some parts I need for the tiller are no longer made (I could have a machine shop make them for considerable expense).

    My old engine was a 1992 2-stroke Mercury 40 4-cylinder. It was used mostly in saltwater non-stop for 25 years, between runs to the camp, 70 mile fishing trips, hunting, wakeboarding, and kneeboarding. I even did search and rescue with it during Hurricane Katrina so I have gotten my money's worth out of it over 25 years of beating the tar out of it. My problem is that I cannot just go out and buy a new Mercury 40 because the weight of the new 4-stroke 40 would sink my boat the first time out. The new engines just weigh too damn much. I can't drop all the way down to a 30 hp engine because I needed more performance not less because I am always loaded down whether fishing or hunting. The old engine had a huge amount of torque for a 40 since it was 4 cylinder and based on the 50 or 60 block of the time, although on the top end they were never considered that speedy. The only company left that even makes a short (15") shaft 40 is Tohatsu and looking at Tohatsu's web site, they do not appear to offer it in a manual start or manual trim. I do not want to start carrying around 120 lbs of batteries just to start the engine (1 battery is fine if you have manual start as a backup), but it would be insane to trust your life to a single battery with no backup. I have been there, done that. The bugs will make you go insane if they don't kill you first when you get stuck out in the marsh during the summer.

    Can you guys think of any solutions to this?

    Thanks!
     
  2. Rubberhead

    Rubberhead Elite Refuge Member

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    Location:
    Moncks Corner, SC
    Like you said, it's paid for itself. Get a new one.
     
  3. Sasha and Abby

    Sasha and Abby Elite Refuge Member

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    Location:
    Columbia, SC.
    Go buy a used one
     
  4. bang you'r dead

    bang you'r dead Canada Forum Mod. Eh! Moderator

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    Location:
    The Pas Manitoba
    I would get it checked out first. Maybe just needs a new pot and piston so you can get back running pretty quickly for a couple hundred bucks. Should be lots of them available on line or through repair shops.
     
  5. Fowler267

    Fowler267 Elite Refuge Member

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    I cooked my 3 cly Yamaha 40 in the yard in a bucket....

    It was cleaned up , honed and had new pistons and rings for $1000
     
  6. Fowl-Action

    Fowl-Action Senior Refuge Member

    Messages:
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    Aug 14, 2013
    Location:
    Colorado
    I'd see if it's fixable first but if not look into the 3cy mercury's from the early 2000's, the 59ci model is roughly 200lbs but can be modded out to 60hp pretty easy. I believe there's also a 52ci model that has a pull start but I don't think you can modify that one much
     
  7. perfmarine

    perfmarine Elite Refuge Member

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    Location:
    Atlantic
    Why didn't you service the water pump on a regular basis. I don't think that 40 4cyl was made in a 15". Look for a 60 3 cyl 2 stroke,they were good motors,easy to rebuild. I have done many because guys don't keep the oil tank full and condensation water gets in the oil tank, first time out in spring and they blow. Never liked the 40 4 cyl, funky carbs,always leaked fuel.

    There is a good chance your motor is ok. Start it up and see how it sounds, wont hurt water pump if it is blown,won't hurt motor for 1 min till it warms up. That motor has no head gasket to blow and leak. Till you can do a compression check.
     
    Last edited: Aug 21, 2017
  8. muddywater

    muddywater New Member

    Messages:
    21
    Joined:
    Aug 29, 2014
    Location:
    LA
    Thanks for all of the replies. I will keep an eye out for a 2000's era 40 or 50 but I am wary of buying something I cannot determine the hours on.

    perfmarine - My engine was a 4-cylinder 40 with a 15" shaft made in Belgium. I have had it for 25 years so I know they exist. Water pump was serviced not that long ago and it was pumping perfectly the day it went out. All I can think is that it was one of those freak things where it sucked up a piece of shell from the reef we were fishing on that was just the perfect size to destroy it. It still turns over but will not start. I tested the compression yesterday. It was from top to bottom, 100, 100, 95, 105 which I suppose is on the low side, but considering it is 25 years old and just got fried, that is not too bad.
     
  9. muddywater

    muddywater New Member

    Messages:
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    Aug 29, 2014
    Location:
    LA
    You are right though that it might not be toast. I am going to find out for sure.
     
  10. mebe007

    mebe007 Refuge Member

    Messages:
    86
    Joined:
    Oct 7, 2016
    With those compression numbers it should still run.
     

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