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  1. #1
    Seaman
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    Default No tach, how to set idle speed?

    So being an older Chrysler that needs that 20 pole tach (I found one that still doesn't work), I don't know the idle speed so it's pretty hard to know what's going on. Is there any way to ballpark that it's idling at the right speed?

    Also, it runs differently with the cowl on or off (obviously since the carb can get more air), so my question is, should I make these adjustments and quickly throw the cowl on, or are the instructions meant to have you set it with cowl off?
    Matt...
    1971 Starcraft 14' Cruiser w/1969 Chrysler 55 HP

    Check out my oldies station! www.oldies104.net

  2. #2
    Lieutenant Junior Grade
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    Default Re: No tach, how to set idle speed?

    You really need a tach. Dosen't need to be dash mounted. One out there called a "tiny tach". ebay usually has them less than $50. You will need a tach for checking rpm at wide open throttle too. Should not run differently with the cowl on or off. No idea about that one unless the air intake ports are pluged.

  3. #3
    Seaman
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    Default Re: No tach, how to set idle speed?

    Here's the closest I got, also included a shot of the 20 pole tach

    http://www.youtube.com/watch?v=jYdACgWvph0

    If I'm too poor to afford a tiny tach, would this one work?

    http://www.ebay.com/itm/12V-Hour-Met...item35bba6b987
    Matt...
    1971 Starcraft 14' Cruiser w/1969 Chrysler 55 HP

    Check out my oldies station! www.oldies104.net

  4. #4
    Fleet Admiral Frank Acampora's Avatar
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    Default Re: No tach, how to set idle speed?

    Well, first off, unless that engine has electronic ignition the 20 pole tach is incorrect. A regular tachometer is the correct application. It takes signal from one set of points and the tach is set on the back for (1) pulse.

  5. #5
    Seaman
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    Default Re: No tach, how to set idle speed?

    My cowl says "Magnapower" model # is 5591, I don't know if that is telltale of magnapower or not.
    Matt...
    1971 Starcraft 14' Cruiser w/1969 Chrysler 55 HP

    Check out my oldies station! www.oldies104.net

  6. #6
    Admiral jerryjerry05's Avatar
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    Default Re: No tach, how to set idle speed?

    Running better with the cowl off????
    There's an exhaust leak somewhere.
    Or a blockage(not likley).
    Find someone with a timing light that has the meter in the end.
    Tiny tacks ain't that expensive.If you buy 2-3 wrong tachs the shipping back and forth would buy the TT
    IF YOUR OUTBOARD DOESN"T START WITHING A FEW SECONDS THEN SOMETHING"S WRONG!!!!

    boats . net is NOT the place to buy parts.They managed to screw up my last 4 orders.
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    Buy American made Cars and Trucks!!!Towing insurance for a boat,a GREAT thing.

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  7. #7
    Commander BonairII's Avatar
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    Default Re: No tach, how to set idle speed?

    Save up...and buy a tach. I almost went the tinytach route, but bought a teleflex for $20 bucks more. Tinytachs have a potted battery, so once it dies...the tach is done(unless you can dig the battery out of the epoxy and replace it.

    A tach will help you run your motor more efficiently(saving gas) and help you prop it correctly(saving gas and increasing the life of your engine).

    Well worth the money IMO.
    1975 Starcraft SS-16' / 1977 Evinrude 75hp now w/ CMC power trim and tilt
    17p prop- 36 mph @ 5900 rpm ( 2 people, 12 gals fuel, 2 batteries)

    1975 Starcraft Super Sport- Resto currently "in progress"
    http://forums.iboats.com/starcraft-boats/1975-super-sport-16-boat-requesting-admission-starmada-2nd-splash-complete-547770.html

  8. #8
    Senior Chief Petty Officer
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    Default Re: No tach, how to set idle speed?

    Quote Originally Posted by gunterm View Post
    Here's the closest I got, also included a shot of the 20 pole tach

    http://www.youtube.com/watch?v=jYdACgWvph0

    If I'm too poor to afford a tiny tach, would this one work?

    http://www.ebay.com/itm/12V-Hour-Met...item35bba6b987
    I actually ordered one of those $15 tach that attaches to the #1 plug. I have yet to receive it but I just plan on using it as a back up or verify the main tach. I'll let you know as soon as I get it and tested. it should work though since it only measures the spark for the #1 plug which in a 2 cycle engine equates to 1 REV.

  9. #9
    Seaman
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    Default Re: No tach, how to set idle speed?

    Quote Originally Posted by jerryjerry05 View Post
    Running better with the cowl off????
    There's an exhaust leak somewhere.
    Or a blockage(not likley).
    Find someone with a timing light that has the meter in the end.
    Tiny tacks ain't that expensive.If you buy 2-3 wrong tachs the shipping back and forth would buy the TT
    That's what I was afraid of, I figured they wouldn't build an engine that needed settings adjusted with it on without mentioning that in the manual.

    Where can I start looking for the leak or block?
    Matt...
    1971 Starcraft 14' Cruiser w/1969 Chrysler 55 HP

    Check out my oldies station! www.oldies104.net

  10. #10
    Admiral jerryjerry05's Avatar
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    Default Re: No tach, how to set idle speed?

    Look in the lower part of the motor cover down inside is a rubber boot that might have slipped.
    Or a small snout that sticks out the back of the motor.Possibly a seal leak there?
    Or worst case,one of the gaskets under the head sprung a leak.
    Start motor and look under the cowl.
    IF YOUR OUTBOARD DOESN"T START WITHING A FEW SECONDS THEN SOMETHING"S WRONG!!!!

    boats . net is NOT the place to buy parts.They managed to screw up my last 4 orders.
    NO communication,NO follow through. Incompetent staff.Nuff said!

    Buy American made Cars and Trucks!!!Towing insurance for a boat,a GREAT thing.

    If you fix your problem,do the rest of the posters a favor and send in one more post telling who,what, how it was fixed.J

    88 Bayliner 21CC Twin 85hp Forces.

  11. #11
    Seaman
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    Default Re: No tach, how to set idle speed?

    I'm assuming this is what I want to look under? I don't really see much here, except that everything is really oily. There's something that looks like a boot down in the corner, but it's attached.

    IMG_0088.jpgIMG_0090.jpgIMG_0091.jpgIMG_0087.jpgIMG_0089.jpg
    Matt...
    1971 Starcraft 14' Cruiser w/1969 Chrysler 55 HP

    Check out my oldies station! www.oldies104.net

  12. #12
    Fleet Admiral Frank Acampora's Avatar
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    Default Re: No tach, how to set idle speed?

    Those early 55sDon't have a rubber boot for the idle relief ports. That single tube that sticks out the back is the idle relief vent. Judging by the amount of oil inside the lower cowl halves, I would guess you have a bad base gasket and it is leaking exhaust into the cowl then down the leg. It is a long job to replace the base gasket--you must completely remove the powerhead--so that is probably why it was never done.

    Again, Chrysler used the term Magnapower quite loosely. These old 55 while labeled Magnapower are usually magneto or battery and points ignition. They use a standard tach but even those do not seem to work very well.

  13. #13
    Seaman
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    Default Re: No tach, how to set idle speed?

    Ah, well the big long gasket that encircles the motor is starting to deteriorate, so that must be it. Before the fuel pump went bad I was able to plane out at top speed, so I'm guessing it doesn't affect you any time except at idle. Maybe it'd be easier to drill holes in front of where the carb is and run a little tube with air filter.

    You can see the gasket I'm talking about at the top of the 2nd picture.
    Matt...
    1971 Starcraft 14' Cruiser w/1969 Chrysler 55 HP

    Check out my oldies station! www.oldies104.net

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