Problem - SE 6-speed tranny installed - leaking oil

Discussion in 'Touring Models' started by TQuentin1, Apr 4, 2008.

  1. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    I am VERY dissatisfied.

    Last weekend, I up-graded my '03 FLHTCUI OEM 5-speed tranny to an SE 6-speed that I bought from Republic HD (Sugar Land Texas) for about $3K and change (including the side cover kit, misc. gaskets, oil, etc.). 200 mi. later, my brand new tranny is covered with oil!! Pulled fill tube, primary cover and starter to see where the oil was coming from. Guess! That stupid little chromed plate and gasket (35153-03 and 35152-03 respectively) that are supposed to seal the old speed sensor location on the case leaked like a sieve!! The screw was tight, but not sealing. This is a crappy solution by HD. Must have been the night-school engineering crowd. They should have designed a profiled cover like the speed sensor itself that fits down in the hole and uses an o-ring to provide a better oil seal. Not sure how to get all the oil off the transmission at this point. Called the Motor Company for their wisdom. They said something to the effect: smear RTV on both sides of the gasket!! WHAT CRAP!! But what did I expect - they designed this rinky-dink setup. So my question is: What is the solution to provide a positive seal on the old sensor location?
     
  2. glider

    glider Veteran Member

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    I would get some gasket material from the auto parts store, it comes in different thicknesses. Then use some RTV on both sides and install it on the case. It should do the trick. Let the RTV skin over before installing the unit.
     
  3. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Glider,

    Thanx for your quick suggestion. I am concerned about the amount (or lack thereof) flat sealing area around the speed sensor hole in the case. The right side of the hole is almost a knife edge. Without any flat area to share the load, I expect this sharp edge to cut through any gasket/RTV material that is surface mounted.

    As an alternative, I am thinking of using a rubber stopper forced in the hole about 1/4-3/8" with about 1/16-1/4" left out of the hole. I will put some rubber washers on the screw side under the chromed plate and tighten this down to hold the stopper in place. What do you think?

    TQ
     
  4. glider

    glider Veteran Member

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    By doing what you say here, it sounds as if you are planning on eliminating the speed sensor which would be a bad move. The ECM relies on readings from that off the 4 th gear cog in the trans to send out the proper info to run the systems on the engine, not to mention the speedometer/odometer and self canceling directionals.Setting a constant code would be a problem also.

    Your remedy would probably work but first I would check on another SE trans to see if you may have gotten a bad casting.

    I would try to keep the sensor at all costs.
     
  5. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Glider,

    I must not have explained myself well enough in my original post. On the SE 6-speed available as a replacement unit, they use the same case as the original 5-speed tranny. Therefore, the 6-speed transmission case has the configuration (hole and tapped screw hole) as the 5-speed. However, in the 6-speed layout, the actual location for the speed sensor is on the top of the trap door. SE has cut a recessed profile that the speed sensor fits in. It is the same speed sensor that was used on the 5-speed. So I am NOT eliminating the speed sensor. The problem I am trying to fix is the original speed sensor location in the case. That is where this goofy design by HD of a gasket and plate is located. It does NOT seal. It came from HD, I unloaded it from the box, installed it on the bike, put the oil in it and then fired up the bike. Within 200 miles, about a third of the transmission oil had leaked out and all over the transmission. I am VERY pissed that I am having to engineer this problem because HD did such a crappy job of it.

    TQ
     
  6. Fearless1

    Fearless1 Active Member

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    I was having problems with my speedo it was tagging 120 as soon as I started moving and racking up the miles at that speed so I just reached down and cut the sensor wires and eliminated the problem that was 2 years ago and bike runs fine without it to this day.
     
  7. glider

    glider Veteran Member

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    I understand now, it sounded like you were looking to plug the opening completely eliminating the sensor. Maybe make a gasket out of some neoprene and use that so the oil doesn't deteriorate it and install it under the plate supplied.
     
  8. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    I tried putting a neoprene gasket under the chromed plate. Did not like the look of things. Felt like it would probably leak. So I went and got a hard rubber stopper (like for test tubes or flasks in chemistry class). cut that approximately 1/4" above the point at which it was tight. Mounted the chromed plate with two rubber washers (about 1/16" thick total) on the screw end. Put some blue locktite on the screw and tightened down on the plate nice and snug. This should hold the stopper in-place nicely sealing the old speed sensor hole. I will keep a close eye on it for a few hunded miles until I feel confident this will work.

    Cheers,

    TQ
     
  9. dangerdan

    dangerdan Junior Member

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    Just a concern

    Not all rubber is the same . Have you checked to make sure this rubber will not break down due to the chemicals in the oil.
    Neoprene is resistant to chemicals.
     
  10. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Your point is well taken, and I am going to run a bit of a science project soaking (submerged) a stopper at room temp for a few months, and heating one in an oil bath for several hours at 300 degF. Will post results.

    This has been a particularly troubling experience with the Motor Company and Republic HD (Sugar Land, TX) for me. I have spent over US$3K up-grading the OEM 5-speed to the SE 6-speed. When I ran into this challenge, I got a trivial suggestion to coat the gasket with RTV and reinstall it from both HD and Republic. This is NOT a good solution.

    The ideal solution, as far as I am concerned, would be for HD to design a plate with a profile that fits in the speed sensor hole and seals with an o-ring (like the speed sensor!). My little "garage engineering" effort was as close as I can get to this idea (no lathe, welding equipment, CNC miller, etc.). I would have assumed that the dealership I bought the SE 6-speed from (Republic) would have gotten concerned when I told them that my brand-new tranny was leaking, and ask me to bring the bike to them so they could look at the problem. Well, that did NOT happen! Instead, I had to buy new gaskets (primary cover, oil fill tube, trannny cover) for about US$42 to put the bike back together after inspecting it for the source of the original oil leak problem.

    At this point, if I had it to do again, I would spend the extra money and buy the Baker DD6. This is a pretty damning testimonial from a diehard Harley owner.

    TQ