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timer base sync/question

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jamyz

Member
someone please help me, i have been fighting a 1973 Johnson 65 hp 3 cyl outboard. originally i didn't have spark to the #2 cyl. i traced the problem to the trigger base under the stater and replaced the trigger base, now i have good spark on all 3 cyl. i have new gas, clean carbs, have sync'ed the carbs to the initial start mark on the throttle cam, removed control cables, is in neutral, but i have to advance the ignition all the way of my idle speed adjustment screw to just start the motor and rough idle. i verified cyl 1 is at tdc with the flywheel mark and the flywheel is correctly torqued. i do not see any other timing adjustment other than this idle speed adjustment on the throttle/timing advance. if i move the timing base linkage to all the way in of my idle screw adjustment, then i can idle but that leaves very little range of movement to wide open throttle. i feel like the timing base is positioned too retarded but im not sure. i put the new one on the same as the old one and connected the linkage with a little slack and the throttle cam lined up with the carbs completely closed and synced together. what am i missing here?? any help is greatly appreciated!
 
This sounds good, but we will need advice from Mr. Scott, Mr. Reeves, Pappy, Racer, Jeff, Boobie, Bobby, Vic, Mechanicman, (who am I missing?)......seems you know what your doing, gonna be hard to figure it out if you did something wrong, but a trigger/timer is an easy job.
 
I thought it was a pretty straight forward job but now im scratching the last of my hair out now. Im not understanding why i have to advance the trigger so far just to idle. There are no adjustments for the carbs, it looks like sync or swim ;)
I keep telling my wife we will be fishing soon but im at a loss of where to go now. Any and all help is greatly appreciated.
 
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My wife would be furious, she loves to fish too....you gotta get it figured out right away. The other techs here need to help, I am at a loss unless the power pack is confused with the new trigger/timer????
 
Power pack is new too. New plugs. All wiring tested. All grounds cleaned. 12.7 volts on the battery. Disconnected control cables to ensure no adverse feedback on the carbs or linkage. Is in neutral when starting. Fuel and oil mix is 50:1. I dunno what other info i could add right now.. I know someone has come across this before, it cant just be my dumb luck...lol, yea it can
 
Simply installing the timer base does not require resetting the full spark advance timing.

The threaded rod that connects the vertical throttle arm to the metal cam. If you, or someone else has changed that adjustment, you will need to reset the idle timing before you can continue on to set the link & synchronization setup.

If that threaded rod is where it belongs, do the following:

Loosen the screw of the roller and back the roller away from the cam. Adjust the linkages between the carburetors so that "all" throttle butterflies are completely shut... and that "all" throttle butterflies open and shut at the same time.. Now... set/adjust the throttle roller so that the throttle butterflies just start to open when the scribe mark of the cam is dead center with the roller.

That's all there is to the Link & Sync thing.

What does you manual say about the idle timing.... a degree setting OR a certain measurement of that threaded rod?

NOTE: The throttle roller since day one has always been a one piece unit measuring about 3/8" in diameter that lasted forever. Some idiot decided to re-manufacture it as a two piece unit whereas the outer portion would eventually break away, reducing the diameter to about 1/8"... and this would throw the entire engine out of synchronization.

Check the roller to make sure that it is roughly 3/8" in diameter. If it is not... replace it.
 
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joereeves said:
Simply installing the timer base does not require resetting the full spark advance timing.

The threaded rod that connects the vertical throttle arm to the metal cam. If you, or someone else has changed that adjustment, you will need to reset the idle timing before you can continue on to set the link & synchronization setup.

If that threaded rod is where it belongs, do the following:

Loosen the screw of the roller and back the roller away from the cam. Adjust the linkages between the carburetors so that "all" throttle butterflies are completely shut... and that "all" throttle butterflies open and shut at the same time.. Now... set/adjust the throttle roller so that the throttle butterflies just start to open when the scribe mark of the cam is dead center with the roller.

That's all there is to the Link & Sync thing.

What does you manual say about the idle timing.... a degree setting OR a certain measurement of that threaded rod?

NOTE: The throttle roller since day one has always been a one piece unit measuring about 3/8" in diameter that lasted forever. Some idiot decided to re-manufacture it as a two piece unit whereas the outer portion would eventually break away, reducing the diameter to about 1/8"... and this would throw the entire engine out of synchronization.

Check the roller to make sure that it is roughly 3/8" in diameter. If it is not... replace it.
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Ok good advice and ive checked all of that minus having a manual for this thing and verified the roller is 3/8". I also verified the cam yoke and throttle lever are 4 31/32" apart. And the carbs are set as described.
 
You got me thinking about that cam roller so i increased it's diameter with 2 windings of tape and she fired right uo and idles perfect so i just needed to open the carbs just a little more. Thank you all for your help with this issue. You saved my vacation :)
 
Hats off to "Uncle Joe", saved the day again. Now put a short piece of proper diameter "heat shrink" to "permatize" it.
 
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Made it to the water bright and early. Had a hard time getting it to start while in the water v/s being on muffs, on muffs it started and ran instantly, so I advanced the idle speed a little, but that's another subject. I pulled away from the dock at idle speed and made it out to the channel and went to throttle up some and she died. I started it back up and at idle speed was ok but no power going forward on the throttle, just sputtered. My wife got to troll for fish some while we emptied 6 gallons of fuel at idle speed for an hour. WOW! Got back home and took the fuel pump off to find a small tear in the inlet side gasket so I made another gasket for that. removed 1 and 2 spark plugs and they were soaked, 3 was clean. Checked my spark again on all plugs and coils = ok. Knowing I have a fuel problem I next turned to the primer solenoid. I found the coil is dead and the internal plunger was melted so bad that it was holding the pathway open for fuel to flow all the time. I removed the plunger and made a new solid gasket to shut off the flow of fuel and that my friends got me back to running normal. So to sum it up, i had 4 problems: a bad power pack, a bad trigger base, a hole in my fuel pump gasket and a screwed up primer solenoid. My wife always told me I was too gassy but I didn't know just how much... Thanks again guys for all your help.
 
Sometimes its best to never give up. I often replace all major spark components together. Its good insurance of success. Gotta "read" my clients based on my interview as well as looking visually and testing the parameters of each component. If they hunt and fish the remote areas, like me, I often push for complete replacement of ignition components that could fail without warning. A final spark coil may not strand you, however, for instance. Most boaters have a bit of cash set aside for these nuisances, if they don't, then they should go to a shop that takes credit cards.
Your very welcome and tell your wife she's probably right.....who else would know anyway.
 
timguy said:
Sometimes its best to never give up. I often replace all major spark components together. Its good insurance of success. Gotta "read" my clients based on my interview as well as looking visually and testing the parameters of each component. If they hunt and fish the remote areas, like me, I often push for complete replacement of ignition components that could fail without warning. A final spark coil may not strand you, however, for instance. Most boaters have a bit of cash set aside for these nuisances, if they don't, then they should go to a shop that takes credit cards.
Your very welcome and tell your wife she's probably right.....who else would know anyway.
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I agree and will change out the coils as well. While im waiting for the new primer solenoid to come in i noticed that there are no washer/screws where the low speed mixture jets are at the front top of the carb, guess the shop forgot to put them back so i need to order those as well.
 
jamyz said:
I agree and will change out the coils as well. While im waiting for the new primer solenoid to come in i noticed that there are no washer/screws where the low speed mixture jets are at the front top of the carb, guess the shop forgot to put them back so i need to order those as well.
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For the 73' 65hp Johnson model 65373R it shows parts number Washer-plug 0317477 & Screw Plug 0317476. My understanding is this screw is turned all the way in and then backed out about 1-1/2 turns to start with adjustment on the center carb. Is this correct? It seems to me these missing plug screws are also a contributing factor to my problem.
 
My recollection is that all three carbs are the same on this idle orifice design whereas the screws that are missing are just a cap in order to properly direct the flow through the orifice. These cap screws are tightened down snuggly, the orifice does the work. If I remember they are a 34 or 35 number.
 
The carburetors on a 1973 model 65 HP do not have a mixture adjustment for idle.-----Those are plugs that are to be screwed in snug !!!----Best to find the real problems.----Maybe I missed it , but what are the compression numbers ?
 
timguy said:
My recollection is that all three carbs are the same on this idle orifice design whereas the screws that are missing are just a cap in order to properly direct the flow through the orifice. These cap screws are tightened down snuggly, the orifice does the work. If I remember they are a 34 or 35 number.
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If the screws are not installed in which i completely overlooked before, what type of trouble would that cause?
 
racerone said:
The carburetors on a 1973 model 65 HP do not have a mixture adjustment for idle.-----Those are plugs that are to be screwed in snug !!!----Best to find the real problems.----Maybe I missed it , but what are the compression numbers ?
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Its about 130 on all 3 cylinders. I've had a couple issues that have been worked through but the main problem now is waiting for the primer solenoid to come in. the old one had a melted plunger and was dumping too much fuel because the fuel flow wouldn't shut off. I found that right after replacing the timer base and power pack because #2 coil wouldn't fire but that is solved. While double checking for any other carb adjustments other than idle speed and sync I noticed the plugs were missing. I believe my last mechanic left them out but he has moved and I'm left trying to figure it all out.
 
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jamyz said:
While double checking for any other carb adjustments other than idle speed and sync I noticed the plugs were missing. I believe my last mechanic left them out but he has moved and I'm left trying to figure it all out.
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If you're speaking of the domed core plugs that seal the fuel passageways... the carburetors are worthless without them. The "mechanic" moved huh?... I'm thinking you noticed the core plugs were missing... he didn't!
 
joereeves said:
If you're speaking of the domed core plugs that seal the fuel passageways... the carburetors are worthless without them. The "mechanic" moved huh?... I'm thinking you noticed the core plugs were missing... he didn't!
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It's the screw that goes over the idle passage as a "plug". I was curious what the effect would be running without these screws in place to just help nail down some issues i've had with this motor
 
jamyz said:
It's the screw that goes over the idle passage as a "plug". I was curious what the effect would be running without these screws in place to just help nail down some issues i've had with this motor
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With the screw plugs and washers missing, as the throttle is increased, "air" instead of fuel would be drawn into the holes missing the screw plugs..... and the engine would fall on its face and bog out.
 
joereeves said:
With the screw plugs and washers missing, as the throttle is increased, "air" instead of fuel would be drawn into the holes missing the screw plugs..... and the engine would fall on its face and bog out.
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That goes along with what i've experienced. I have to get this new primer solenoid in place and put those carb screws in and go from there. This has been a mystery unfolding but with all your help i'm starting to understand the whole issue...thanks again for all your help guys!
 
Actually the primer is an improvement over the original choke flappers.-----Any more pictures of the motor including powerhead and shift linkages?----Perhaps a newer powerhead was installed !!----That might also explain the " missing " plugs on front of carburetors.----At this time there is a need to establish what you really have here.----Here I go being a detective / forensic fixer again.
 
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racerone said:
At this time there is a need to establish what you really have here.----Here I go being a detective / forensic fixer again.
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Amen!... Yeah, got me wondering if those missing screw plugs need to be missing.If that powerhead was changed, including carburetors, etc... those carburetor idle jets would be "idle air bleed" jets which dare not be plugged off.
 
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