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  1. #1
    Join Date
    Jun 2009
    Location
    Republic, WA, USA
    Posts
    2

    Default "Hi, my 98 BF40 does not overh

    "Hi, my 98 BF40 does not overheat (no light, no rough running, no steam) but the tell-tale is intermittent at any speed. I installed a new pump impeller and housing, pulled the t-stat and checked it's operation in water on the stove. No obvious corrosion, and while the t-stat was out I blew air through the tell-tale with a compressor. Launched it, peed for a few minutes and quit. What do yall think? Loose crud? If so, how do I get rid of it? Thanks in advance for your help, and I hope it's not BPH!"

  2. #2
    Join Date
    Jun 2009
    Location
    Austin, TX,
    Posts
    3

    Default "Sounds familiar. I just finis

    "Sounds familiar. I just finished a tear down to solve the same issue. The water flow from mine eventually stopped completely. The culprit - a disintegrated impeller over 2 years ago that had built up a clog at the T in the bottom of the cylinder head. I did the blow/flush out when I replaced it but pieces still existed in the system. The T is formed where the water up tube from the impeller comes into the engine and splits to go to the cylinder water jacket and the overflow tube that runs back to the thermostat housing. These pieces where jammed in so tightly I had to use a screw to flake them out.

    It now pee's like a race horse.

    To pull the block from the case is not hard. First disconnect the shift linkage and remove the upper case and the pivot bracket. There are 4 bolts around the perimeter, one in the middle by the exhaust, and 3 up in the drive shaft housing. Drain the oil first and be careful of the wiring. I pulled the cylinder head also but probably did not need to to get to the inlet.



    Base of Engine block - up tube inlet - BF8A"">

    Egine block bolt locations - BF8A"">

    Impeller pieces clogging engine water inlet"">Overflow tube at base of engine block - BF8A

  3. #3
    Join Date
    Jun 2009
    Location
    Republic, WA, USA
    Posts
    2

    Default Thank you Chris!!! I did as

    Thank you Chris!!!

    I did as you suggested and found a piece of an old impellor that caused the problem. I really appreciate the details you gave me that helped me complete the job.

  4. #4
    Join Date
    Jun 2009
    Location
    Darwin, Northern Territory, Australia
    Posts
    58

    Default "Hello there, I have a honda 5

    "Hello there, I have a honda 50 with the same problem. Are you saying to lift the engine off or are you talking removing all the lower leg stuff (up from the prop to the bottom of the engine housing?)

    Regards

    Chris"

  5. #5
    Join Date
    Jun 2009
    Location
    Austin, TX,
    Posts
    3

    Default "Here's a pic that shows t

    "Here's a pic that shows the engine still in the case and the location of the blockage. Drain the oil first to avoid a mess. For the larger engine you might want someone to assist in lifting the engine from the case-especially if you leave the cylinder head assembled to the block. Watch the wiring in the front when moving the engine around - I broke the ground connection at the neutral switch and that caused it not to start when I put it back together.

    Blockage point on BF8A

  6. #6
    Join Date
    Jun 2009
    Location
    Darwin, Northern Territory, Australia
    Posts
    58

    Default "Chris, Thanks for that. Wh

    "Chris,

    Thanks for that. Where yours shows the outlet, mine has a threaded fitting. Took it out, put in the wash fitting for the leg, attached hose and out popped the rubbers. There is a god, didnt quite pull the whole thing apart, but had taken the gearbox off..."

  7. #7
    Join Date
    Jun 2009
    Location
    Darwin, Northern Territory, Australia
    Posts
    58

    Default Chris Can you direct me toward

    Chris Can you direct me towards where the thermostat might be on these motors?

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