1970 85 hp V4

Home Forum Ask A Member 1970 85 hp V4

This topic contains 65 replies, has 8 voices, and was last updated by  fleetwin 1 year, 7 months ago.

Viewing 15 posts - 31 through 45 (of 66 total)

  • fleetwin
    US Member - 1 Year
    Replies: 2456
    Topics: 29
    #58592

    An electric/air impact gun will usually remove the flywheel nut, eliminating the need to wrestle with the ring gear holder etc…The same impact gun can be used on the OMC puller nut to pop the flywheel off…There is no need to remove the flywheel to check spark and it is OK.
    But, again, have you checked it for spark? There is no need to remove the flywheel if spark is OK. How far into this thing do you want to get involved? You mention wanting to end up with a Homelite for power. Like Frank has said, the electrical parts for this engine are very expensive, if you can find them, I don’t think you will find a replacement powerpack for under $200. So, I would recommend checking for spark before digging much further into this project. Again, you will need to use a jumper to the pack post on that terminal board while cranking because you don’t have a wiring harness. You can move forward to evaluating the gearcase if you find good spark.
    Perhaps I have not read your posts thoroughly, I don’t mean to keep repeating myself. I just don’t want to see you dig farther into this thing than necessary, especially if it has spark and shifts OK.
    Once you have confirmed spark and gearcase operation, you can search for a decent used control box/wiring harness. Again, you will want to check shift switch operation with an ohm meter. These control boxes are getting tougher to find in decent condition, but they are still out there.
    PS- Yes, these engines will run backwards, which is why that goof anti reverse spring is there and must be functional…

    OK, just reread your posts. The ATF fluid may or may not work, but let’s give it another try. Are you sure the gearcase is full of fluid? The gearcase must be filled from the bottom plug until it flows for the top vent plug. In order to power up those solenoids, you must slide those rubber sleeves back on the shift lead connections coming up from the gearcase. This operation is tricky enough, try spraying a little WD40 into those sleeves before attempting to slide them back. Once the sleeves are out of the way, you can disconnect the two knife connections. There are two shift solenoid leads, one is green the other is blue. I can’t remember which lead is which, one is the neutral lead, the other is the reverse lead. When in neutral, only one lead is energized, both leads are engergized when in reverse. So, for now, let’s just energize both leads. I am assuming you will just jumper cables to crank the engine. So, the negative jumper cable should provide a good ground for the shift circuit. You will need to carefully run a jumper lead from the battery positive to both shift switch leads being careful not to let this connection hit the engine block/engine pan creating a direct short. Now you can connect your positive jumper cable lead to the starter positive. Then, while you are watching the prop shaft, have an assistant connect the positive jumper cable lead to the battery. You will probably see the prop shaft rotate clockwise for a few rotations until pressure is built up, then it will rotate counter clockwise in the reverse direction while cranking. Again, you will need a decent 12 volt battery that is fully charged, a little battery out of a riding mower/motorcycle won’t do. Once we confirm reverse works, I’m sure Frank will tell us which lead is the "neutral lead". Then, we can connect only that neutral shift lead to B+ while cranking to see if neutral works. Chances are pretty good that neutral will work if reverse works….Again, it is important to understand that both leads must be energized for reverse to work. If the gearcase fails these test, you can check the solenoids for continuity, we will research the resistance value of the solenoid, but I seem to remember a value of about 6-7 ohms. I would also drain the gearcase and refill with OMC premium blend before condemning the gearcase as well…


    garry-in-tampa
    Lifetime Member
    Replies: 2914
    Topics: 29
    #58597

    The purpose of the electrohydrolic shift was to shift faster and with more force than mechanical while overcoming the electric shift failure to neutral. In the event of electrical failure it would default the forward and get you home. Like all outboard lower units, it needed lubrication that water did not provide. . . 😉


    frankr
    US Member - 1 Year
    Replies: 3850
    Topics: 43
    #58601

    Holy Moly, Garry. Where did you dredge that oil pump up? From the middle of Tampa Bay?


    garry-in-tampa
    Lifetime Member
    Replies: 2914
    Topics: 29
    #58607

    It was an example of "Don’t let this happen to you" in a service manual. An advertisement for OMC’s special oil . . . 😆


    amuller
    US Member - 2 Years
    Replies: 788
    Topics: 125
    #58634

    OK, everybody seems to think I should focus more in ignition, so I’m checking that out. Coil found is 580740, German. Sec. resistance measures 3K. Primary resistance (blue lead to black lead) ohms out as close to a dead short (0.1 ohm). I couldn’t find any specs for this coil. Does this seem anywhere near right?

    I’m a bit cautious about proceeding, now knowing if a shorted coil primary would mess up the "amplifier."

    Thanks.


    fleetwin
    US Member - 1 Year
    Replies: 2456
    Topics: 29
    #58642

    Does this engine have spark or not? The resistance seems normal for the coil….


    amuller
    US Member - 2 Years
    Replies: 788
    Topics: 125
    #58643
    quote fleetwin:

    Does this engine have spark or not? The resistance seems normal for the coil….

    It produces a nice 1/2" spark from the coil lead when the wire to the points is scratched. Point’s don’t appear to be making, by meter, and there is no spark from the coil while cranking. So I presume the points need attention. Need to pop flywheel next.

    That "reverse cutoff spring," 313743, $39. Is it something I should expect to have to replace? Is it important? Does this motor have some special tendency to start backwards?

    Interesting discovery: The red-painted battery terminal was on the negative cable, and the black one on the positive. So likely this setup has been connected with reverse polarity. So I expect various burn’t out diodes and suchlike. Interesting that the amplifier survived.

    Time to check the shifting again…..


    amuller
    US Member - 2 Years
    Replies: 788
    Topics: 125
    #58647

    So it shifts!


    frankr
    US Member - 1 Year
    Replies: 3850
    Topics: 43
    #58650

    Hoo-Rah! 😀


    eviltwin

    Replies: 68
    Topics: 5
    #58653

    I may be too late, but I had an Evinrude 40 hp with the push button hydro electric shift. I lost reverse the last year I owned it. I cleaned all the contacts from the box on the back of the motor and (if I recall correctly) it turned out to be the ground wire that went to the bolt on the cylinder head that fixed it. Wished I had found that sooner. It was a pretty decent motor, had it on a pontoon boat. One other time it got left out in a monsoon and would not turn over. That turned out to be the connections inside the shift lever box. They literally were green and furry. Cleaned all of those an it worked like a champ. I pretty much drained & refilled the lower unit every time I used it.

    Good luck!


    amuller
    US Member - 2 Years
    Replies: 788
    Topics: 125
    #58657

    Thanks. I can’t believe I failed to check the polarity of the battery cables! Not a mistake I will every make again. Evidently the shift solenoids are polarity sensitive in some fashion. Plus, my Fluke meter is getting flaky. It’s been an interesting learning experience, with outstanding coaching from this board. Now to find my 1 5/16 socket and pop the flywheel.

    I also have a 40 hp Big Twin with the "Selectric" shifting–spring clutches I think. I’ve checked and it does shift but not gotten into it beyond that.


    eviltwin

    Replies: 68
    Topics: 5
    #58682

    One other thing I remember, would not crank over if throttle lever was above start, even a little. Built in safety. It would start in gear and you had to be careful shifting, I did hit reverse a few times trying to put it in neutral and hitting the wrong button. Didn’t seem to harm anything. Always wanted the Johnson Controls for this reason and it was harder to dock cause you needed to hit the buttons which takes your hand away from steering or throttle. The little silver momentary switch under keyswitch was choke, as mentioned.


    fleetwin
    US Member - 1 Year
    Replies: 2456
    Topics: 29
    #58686
    quote amuller:

    quote fleetwin:

    Does this engine have spark or not? The resistance seems normal for the coil….

    It produces a nice 1/2″ spark from the coil lead when the wire to the points is scratched. Point’s don’t appear to be making, by meter, and there is no spark from the coil while cranking. So I presume the points need attention. Need to pop flywheel next.

    That “reverse cutoff spring,” 313743, $39. Is it something I should expect to have to replace? Is it important? Does this motor have some special tendency to start backwards?

    Interesting discovery: The red-painted battery terminal was on the negative cable, and the black one on the positive. So likely this setup has been connected with reverse polarity. So I expect various burn’t out diodes and suchlike. Interesting that the amplifier survived.

    Time to check the shifting again…..

    OK, so it sparks at the coil when the lead from the points is tapped to ground, but not when cranking…So, it does seem like you will have to remove the flywheel, unless the ground lead coming from the ignition point plate is not making a good connection. Perhaps the leads are frayed/broken.
    The points are probably just a little dirty, there are two sets which are gapped at .010". The anti reverse spring could be causing a problem if it is somehow stuck grounding out the circuit, doesn’t seem likely though. The anti reverse spring is probably in OK condition and does not need to be replaced, but it is a needed item and should be replaced if it is NG. I am assuming you have a decent OMC manual for this engine that will explain servicing procedures in great detail.
    Yes, if those battery cables were crossed, even for a second or two, I am quite certain the alternator rectifier diodes are shot, the shift circuit diodes may have been damaged also. We will get back to this after the ignition is straightened out. Be sure to check the resistance of the alternator windings while the flywheel is off, it is unlikely that crossed cables damaged the windings though.
    Great news, the gearcase shifts OK, I thought it would. Did you fill with OMC premium blend? Normally, I would recommend doing a water pump job, but not in this case. Again, I don’t want you digging into this thing any farther than absolutely necessary. Once the ignition is straightened out, you can search for a decent control box/wiring harness…


    amuller
    US Member - 2 Years
    Replies: 788
    Topics: 125
    #58703

    The flywheel popped off with no special effort. I’m not sure it was fully torqued.

    The alternator stator tests .9 ohm lead to lead and is not grounded. It’ looks fine. Somewhat to my surprise, the rectifier diodes test good with a forward voltage drop of about 0.5. I still need to check the brown diode lump related to shifting, and the "clipper" box. I take it this is clipping in the sense of spikes? I’m a bit puzzled about how the distributor itself actually works. Manual time…..


    fleetwin
    US Member - 1 Year
    Replies: 2456
    Topics: 29
    #58711

    Don’t know just how you tested that rectifier, but there are six diodes that are checked with an ohm meter set to the high scale. There are a few diodes in those shift diodes as well, the manual spells out the test procedures. The alternator winding resistance value you mention seems about right, will attempt to find a manual to confirm.
    That "clipper circuit" is a lame attempt of protecting the powerpack/amplifier from voltage spikes resulting from poor battery connections. The alternator windings are shorted/perhaps grounded when high voltage is sensed. The procedures for testing it are in the book, although a little vague/confusing. Like I said, the rectifier is usually damaged quickly, even if the cables are reversed only momentarily. I suppose there is the chance that the cables were never reversed in spite of the red tape on the negative cable.
    I would agree, the flywheel was probably not torqued properly if it came off relatively easily, be sure the tapers are clean and dry when you reassemble. The coil threads into the distributor, its voltage is routed to the rotor through a tab in the center of the distributor, the outer tab on the rotor delivers voltage to the four plug wires through copper/brass tabs on the outer edge inside the distributor. There is the possibility that the distributor/rotor is leaking/arcing causing the no spark condition, this can only be checked using coil tester to supply power to the distributor, then probing for leaks. These items are pretty expensive if you can find them, so I would no just replace them unless you can confirm they are leaking/arcing.
    Did you have a look at the points? Are they gapped correctly? Was the anti reverse spring present, was it working correctly? If the ARS is somehow jammed/stuck on the ground tab, this would cause a no spark situation. Be sure to use a little Loctite on the stator screws during reassembly.

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