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Thread: more problems

  1. #1

    Default more problems

    so last night we took the boat out again and the hot light came on again. I checked the water port and it had a good stream. The water coming out was warm but not hot. There was white smoke coming out of the exhaust ports. This is engine has never done this it has 130lbs compression on each cylinder. I changed the spark plugs to champion and put in a new inline filter before i took it out gapped the plugs at .30. im at a loss as what to do. forgot to mention its a 2000 70hp jhonson 2 stroke

  2. #2
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    Default Re: more problems

    Quote Originally Posted by outback32 View Post
    so last night we took the boat out again and the hot light came on again. I checked the water port and it had a good stream. The water coming out was warm but not hot. There was white smoke coming out of the exhaust ports. This is engine has never done this it has 130lbs compression on each cylinder. I changed the spark plugs to champion and put in a new inline filter before i took it out gapped the plugs at .30. im at a loss as what to do. forgot to mention its a 2000 70hp jhonson 2 stroke
    White smoke ? Id guess that was steam because there is inadequate flow of water through the engine

    A good stream from the telltale only indicates that the pump is pumping water up to the power head. It does not confirm that there is a flow through the engine

    The water passages could be clogged or scaled. The thermostat could be defective

    It's relatively simple and costs nothing to test the thermostat
    Last edited by vics; 05-23-2020 at 07:31 PM.

  3. #3

    Default Re: more problems

    I will check the thermostat how do i check the water passages are clear if the water comes out of the pee hole

  4. #4

    Default Re: more problems

    by cleaning the water passesges do you mean flushing the motor

  5. #5

    Default Re: more problems

    so i removed the thermostat and tested it. it is stuck in the open position. I thought it would be stuck in the closed position if it was overheating.

  6. #6
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    Default Re: more problems

    Quote Originally Posted by outback32 View Post
    so i removed the thermostat and tested it. it is stuck in the open position. I thought it would be stuck in the closed position if it was overheating.
    That's not the cause of the problem then, You may be able free it up and get it working again ( I did with mine) or you will have to replace it.

    Now you will have to turn your attention to the water passages You will probably have to clean them by hand but it might just be possible to clean them by flushing with an acid descaling solution

    A sulfamic acid based boiler descaler ( I don't know what you will have available) or a marine descaler such as Rydlyme

  7. #7
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    Default Re: more problems

    Was there any evidence of scale in the thermostat area? Perhaps it was stuck open from deposits and infection.
    Last edited by timguy; 05-25-2020 at 04:51 PM. Reason: Typo

  8. #8

    Default Re: more problems

    there was no evidence of scale in the thermostat housing. is there anyway it could have something to do with the idle not being right. maybe the air fuel ratio is set wrong

  9. #9
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    Default Re: more problems

    Likely not related to overheat alarm. The sender could be off target. An infrared gun is handy and fun.....you can check for Covid. I use mine for steaks, barbeque, deep fry, water temp, testing thermostats. 25 bucks at Harbor Freight.

  10. #10
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    Default Re: more problems

    Edit...….

  11. #11
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    Default Re: more problems

    Is the overheat alarm sounding? Have you yested to see if working?
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  12. #12

    Default Re: more problems

    The alarm has been removed by the previous owner because it would always go off because the vro was removed

  13. #13

    Default Re: more problems

    what service manual should i get to work on this engine myself. are the Haynes manuals good or should i get the one fro. a jhonson dealership

  14. #14
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    Default Re: more problems

    Are we talking about the temp alarm, or oil alarm?

  15. #15

    Default Re: more problems

    I just flushed the engine and I noticed it took a minute to get water through the pee hole. then when I went from forward or reverse back to neutral the water would stop for a second then pick up again. as for alarms the only alarm removed was for the no oil but I dont see any other alarms under the dash

  16. #16
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    Default Re: more problems

    Reinstalll the alarm!!! Oil and temp use the same alarm module. Either they didn't disconnect oil tank or VRO was bypassed to use as pre-mix pump and they forgot to unplug harness to VRO
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  17. #17

    Default Re: more problems

    This just doesn't make any sense to me I have never had any problems with this engine getting hot until the trip that night in low water. Now I notice the stream from the tell tale is not that good. it actually stops flowing when going from forward or reverse to neutral. is there a chance the water pump is going out even though it was just replaced last year. or is it mors likely i sucked mud or sand up and blocked water passesges

  18. #18

    Default Re: more problems

    by the way this engine is freshwater only no saltwater

  19. #19

    Default Re: more problems

    If the stream from the pee hole is weak, just replace the impeller. It's cheap and easy. However, the motor could be pissing like a fire hose and zero water or very little could be going through the power head. The overboard water indicator (pee hole) is branched off before the water gets to the motor. The only thing it tells you is the water pump is pushing water up to that point. The water passages in your power head may be clogged up severely. You also may have issues with what the previous owner did when they removed the VRO. I highly recommend getting a manual and going through the alarm wiring and figuring out what the last guy did before you start spending money. The Seloc manuals are ok but I hear some of the information is incorrect. For what you are doing I think it would be fine.

  20. #20

    Default Re: more problems

    Thank you everyone for the help I have a manual on the way. my wife ordered it while I was at work I hope its the right one. Its a actual jhonson manual it says 40-70 hp 2000ss on the cover. I hope that means its for a 2000 model year

  21. #21

    Default Re: more problems

    well ive made some progress I flushed the motor again and good water flow has returned. I let it idle in the bucket for 20 minutes and revved it in forward and reverse. The engine never got even warm. I could touch the cylinder head and it was not hot at all. But all 3 lights are on on the tach check engine hot light and low oil. low oil is always on because the vro isnt connected. but the other lights are normally off.

  22. #22

    Default Re: more problems

    well at idle the engine gets to 165 within a minute. I take the thermostat out and its fine between 95 and 100. The thermostat os stuck open it doesn't make sense. I have a new thermostat on its way. but im afraid its not going to help but no idea what else it could be

  23. #23
    Join Date
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    Default Re: more problems

    well at idle the engine gets to 165 within a minute.
    That temp is close to normal for idle....
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  24. #24

    Default Re: more problems

    ok I thought it was 140 the 165 is why i was worried i shut the engine off before it got any hotter

  25. #25

    Default Re: more problems

    I have a infared thermometer now and new thermostat. I know with the old thermostat in it would get to 167 in less than a minute. and you couldn't touch the head at all without getting burned. I figured if it was cooling right you should at least be able to put your finger on the head for a few seconds.

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