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Process to start newly rebuilt FX HO

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  • Process to start newly rebuilt FX HO

    Good morning,
    Wondering what you experts do to start a newly rebuilt MR-1 HO engine? Curiously mainly about if you remove plugs and crank to build some oil pressure, and how do you confirm that? Or, do you just put in 4 quarts and start her up at low RPM? I followed all manual procedures with regard to oiling bearings, sleeves, etc, but still want to make sure i dont do any unnecessary wear/tear when i start. Current plan is to just start and run a few seconds. If it starts, stop and connect hose so i can let it idle for a minute or so before dragging it to the lake.
    If it does not start right away, i am sure i will post back.

    I will print out the break-in procedure and follow that once i get it to the lake.

    Thank you in advance,
    David in SC

  • #2
    Be very careful when you fill the engine with new oil.
    There are 2 separate places to add oil. Crankcase
    Valve cover.

    Make sure you put the correct amount in the valve cover.
    Someone on here that knows more can help.

    Google it.


    • #3
      Thank you Hurricane1000. I'll double and triple check, but looks like about 3 quarts into the oil resorvoir and about 1.5 into the valve cover? I assume i pop out the rubber plug and add there?

      Does this sound about right?

      Thanks again,
      David in SC


      • #4
        OK, i mocked up my original engine, and popping the grommet off the valve cover will not work because there is one of the valve cover gasket figure 8 seals under it. Glad i did not go that route. Looks like i have 2 other options:
        1) Remove one of the valve cover screws - the one closest to the A on the end of Yamaha. Pouring through this hole will allow the oil to drain almost straight down to the pan. Is this a good option?
        2) Maybe better is to remove the rubber hose that runs between the valve cover and the oil reservoir and pour through valve cover side. This will allow the oil to run straight down the timing chain channel, where it should then drain into the pan. Maybe it will put a little oil on my chain on the way down.

        C'mom Team, can anyone confirm the best way to add my 1.5 quarts to the pan on an empty, freshly rebuilt MR-1? I know someone else has done it, and i am just being overly cautious as i don't want to do this again. Finding a rebuildable engine and tackling the rebuild has taken my whole Winter.

        Thank you,
        David in SC


        • #5
          Here is a photo showing the 2 options for filling some of the est 4.5 quarts of oil through the valve cover gasket. The left is the tube that goes to the oil tank. I assume this is the best place, as the oil will drain straight down the timing chain channel and leak back into the oil pan?
          Or, i can remove the cover screw just to the right of the last A in Yamaha. This sits right over the block oil return port, and should also allow the oil to flow freely to the pan.
          Any advice on which to use? Just a bit nervous as i do not want to starve any parts when i first start up.

          Thank you in advance,
          David in SC
          Attached Files


          • #6
            If you oiled all the contact surfaces bearings and cam during the rebuild then they should still have an oil film on them. I always use lucas assembly lube when building engines that way i can ensure not dry surfaces when cranking. I also fill the engine oil tank with oil 3 to 4 qts then crank the engine over with the plugs not installed for a minute or 2 to build oil pressure then its safe to start then I install plugs start engine let idle till up to operating temp before i rev on it at all then just break-in.


            360?? PRODUCT VIEW

            Lucas High Performance Assembly Lube


            • #7
              Thank you pwcnerd. I cranked a few minutes ago, and she purred like a kitten. Now i will begin the break-in process.

              Thank you for your advice,
              David in SC


              • #8
                Well, thank you all for the help. I have both good news and bad news...............little history first:

                I found a "donor" 6B6 engine out of a wrecked hull. Got a great deal on it, but it had some potential issues. Seller bought wrecked hull and parted it out...unknown hours, and saltwater use. Had some water in the oil, but to me it did not look emulsified, so i sort of wondered if it just got in when it was wrecked/towed. Intake valves were shiny clean too. PO said he cranked it briefly just before removing it. Lots of unknowns. I did compression check on cold and got three at 110+ and one at 75. Added oil to the low one and it came in line. So, i tore it down completely to rebuild. I am not an experienced engine builder, so i am sure i did some things that would be frowned upon by those of higher skill levels, but i am also on a very tight budget and was(am) hoping to make this a useable toy for my grown children.
                I used all OEM parts for my budget rebuild. Crank bearings looked great so i re-used. Rod bearings looked very good, but i replaced anyway. All new OEM rings, yes the low cylinder had one stuck. Honed to a perfect crosshatch. I did nothing other than surface cleaning to the head, as it LOOKED good to the naked eye to me. It did have horizontal cracks in the block outside the water jackets on the outside, so water would have been leaking external while running. I prepped and JB Welded these..........sort of risky, but way too thin to tig weld, IMO. Assembled all back per the Yamaha spec manual. Put in new thermostat, and hoses where needed, including new SBT donut in the exhaust (OEM had way long lead time). I did re-use the exhaust manifold gasket, as it looked pretty good to me after a little cleanup.
                Machine cranked right up and ran well. Idle speed a little low, so would cut off if off throttle completely; i can adjust that. Ran on hose for a few minutes before taking to the water.

                Put in lake and putted around for 30-40 minutes at just above idle RPM....all looked great. No lights, water and oil flowing good. Stopped to check oil level, and it was about a cup low, so i added. Took out for another spin at about 3-4000 RPM varying RPM the whole time. Very boring, but necessary. Did this for another 15-20 minutes. Back to land to check oil one more time. This time, i have water in the oil. Oh crap, what have i done?

                Not a whole lot of water, but definitely there. Froth on the filler cap. I assume a compression check is the first line of order? Assuming that checks out, where should i look next? Water pipe coming through valve cover? Exhaust manifold gasket ( I admit i guessed on torque on those as my body cannot contort enough to get those to proper 25 lbs. I think they are close. Anything else come to mind?

                I am a bot disappointed, but not terribly surprised. I know there is risk in every adventure, but i love to learn and feel like this is yet another learning. I appreciate you all's help along the way.

                David in SC


                • #9
                  It could be as simple as a bad oil cooler. But, from the other damage, it sounds like maybe the head could have an internal crack. Use some rubber plugs and plug off the exhaust and coolant outlets and pressureize the coolant side with spark plugs out. Use a mechanics stethoscope with a piece of tubing on the end to listen for air leaking somewhere.


                  • #10
                    Great advice Myself - thank you. I will have to think on that to figure out how to do it, but it sounds logical. Sounds like you have done this before! Is there a reliable way to test the oil cooler?


                    • #11
                      Oops, just remembered you have 1.1l like ours. Oil cooler is part of the tank at the rear.....I don't know if it can actually pass water INTO the oil. Maybe somebody else could chime in. As for pressure testing. Get a rubber expansion plug to block off the exhaust, then pinch off the pisser lines, water inlet, and water outlet hoses in the rear. That will effectively SEAL the ccolant system. Once pressureized to about 20psi, you should not hear any hissing or bubbling in the spark plug holes OR in the oil tank.


                      • #12
                        Great - thank you. My rationale for not having the head pressure tested while it was off was, at least to me, fairly simple; the motor came out of a unit that was wrecked. I sort of figured previous owner wrecked while running????? Does not make much sense that one was running a unit with serious motor issues and then wrecked? Who knows, maybe they wrecked it knowing it had recently developed motor issues and wanted insurance money? Never know.
                        I really appreciate the advice. Hope to do simple compression check this weekend. It is now 1.5 hours away, so no longer in my basement.....ugh.


                        • #13
                          Meh, not looking good. I ran it a bit this WE to confirm it is getting water in oil, and it is. I ran/stopped/measured several times, and the level is increasing. I put together all the pieces of the original engine last night to try to understand possible causes. I see 1 intake into the oil cooler/reservoir, but no output. I will use compressor this eve to see the potential for that to cause water in oil. Other than that, i can see no real potential source other than head or head gasket.

                          I may try the pressure tests if i can figure out a good way to do it. If not, i may go ahead with removing the head.......without removing the engine. Engine removal is also an option, but i was hoping to avoid that. After doing it once, probably much easier the second time......just getting behind on projects right now.

                          Any other thoughts come to mind on how water can be getting into my fresh rebuild? I checked cold compression this weekend, with my cheap tester, and 1 and 2 were about 100, and 3 and 4 were about 92. Again, cold engine and cheap tester. Does this tell me anything?


                          • #14
                            OK, was able to seal off cooling system inlets/outlets, and then blew low psi air into the plastic manifold that feeds the 4 small exhaust manifold gaskets.. I did this while i had a stethoscope on. Cylinder 3 clearly has air movement....sounds almost unrestricted. Cylinders 1, 2, and 4 have no air movement.
                            Does this clearly indicate head gasket and/or head? Seems like a yes to me........just trying to find any reason to not tear back into this thing.

                            Oh yeah, i found the cooling outlet on the oil tank; right behind the thermostat housing. The oil cooler is a double wall system; i cannot see how it would leak unless a tank wall actually cracked. I don think that is my issue.

                            Thank you kindly for the advice.
                            David in SC


                            • #15
                              You should hear nothing.....just like the others. Sorry, head has to come off bro. If it's the gasket, it will be noticeable. Otherwise......cracked head.