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1975 Evinrude 6hp 6504R, Throttle Automatically Decreases if Not Held in Place

S

Swarlos

Regular Contributor
The title pretty much says it. The throttle handle works well when the engine is off, but when it is running the throttle automatically decreases if I don't hold it in place. This happens both in neutral and in gear.
 
There should be a tapered " friction piece " and a spring way up inside the throttle grip.--------Perhaps it is due for inspection.-----You are sure that the coils are not rubbing on the flywheel ?
 
I did open up the grip and noticed that the tabs that slot into the metal arm on the "Block, Grip Friction 0303282" were a little worn. I haven't checked the coils rubbing on the flywheel, do I have to pull the flywheel to check that or can I just look in underneath?
 
Almost a given. Coils are rubbing. You can feel them grabbing if you turn the flywheel slowly by hand (Plugs out).
 
Fact-------The factory / dealer had a special tool to set the coils in the right place.-----The coils can be adjusted.------You could use tape on the heels to check clearance.-----Or wait for someone to post a picture of how to set them using the mounting boss visually.
 
Coils sit on posts with ground edges at the ends of the coil laminations. Coils should be even with those ground edges.
 
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(Magneto & Driver Coil Alignment)
(J. Reeves)

To align the coils properly, have the metal vertical portion of the coil yokes aligned with the inside edge of the bevel that exists on the top portion of the aluminum seat upon which the coils sit. This creates the proper distance between the coils and the flywheel magnets. Faulty alignment creates friction and the yokes of the coils heat up, turn blue and expand.
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NOTE: That friction block inside the tiller throttle grip handle... Some boaters do the mistakable... and grease that thing. It's a "Friction Block" and grease reduces it to a slippery nothing! If it's greased, clean it thoroughly to renew it's "friction" purpose.
 
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Strange then that a FACTORY manual that I looked at calls for greasing the friction block.-----Perhaps the owner of this motor should consult a manual.
 
I figured you'd go to the trouble of digging that up.... what in the hell is wrong with you?

That statement of the service manuals is one that I strongly disagree with and consider it to be one of total stupidity. For a item to be manufactured to produce friction.... grease eliminates that condition completely, and therefore, obviously, I don't give a damn what the manual states on the subject!
 
And what is wrong with you ?-----There must be hundreds of mechanics making this mistake them.-----I always find them with grease and will always grease them.------Nature will fool you.------Take for example the electric shift lower unit of the 1960's.-----Parts are bathed in oil .----Spring wraps around a drum and drives the boat.----They don't slip covered in oil !!
 
The friction block was clean when I opened up the grip, and I'll leave it that way for now. I'm going to upload a few pictures of what I found under the flywheel in an hour or two. What torque should I apply to reinstall flywheel nut?
 
racerone said:
And what is wrong with you ?-----There must be hundreds of mechanics making this mistake them.-----I always find them with grease and will always grease them.------Nature will fool you.------Take for example the electric shift lower unit of the 1960's.-----Parts are bathed in oil .----Spring wraps around a drum and drives the boat.----They don't slip covered in oil !!
Click to expand...

What's wrong with me?... Well, I'll tell you hotshot! Ever since day one when you came on this site, you've been full of insults and slanted corrections to other members posts that may have been ever so slightly in error on some minor point... and quite frankly I'm sick and tired of it! Back when you first joined up in 2010, roughly nine years after I was invited by Andrew to join up, you had the audacity to actually call one of my replies "rubbish" to which you may recall I pretty much lit into you at that time. If you don't recall, you'll find it in the 2010 archives I'm sure.

You come across as Gods given gift to the marine line, superior to all concerned with the intellect that apparently exceeds Einstein, however that is of no concern to me... unless it affects me. For awhile there, I thought that you had actually mellowed... false alarm!

Now, your comeback which branched off into the original electric shift setup whereas a lubricant does not affect the friction type hold of the shift springs upon the related shift hubs. Although I see no comparison between that setup and the friction block within a tiller handle......................

That shift setup functions only when submerged in a special lubricant especially and specifically designed for that purpose, namely "Type C", also known as "Premium Blend". However... in time, even given the best of care, even with "Type C", that forward hub setup will slip. Put grease on that hub and/or spring... or simply use HiVis (or any other kind of oil) with that type setup and I guarantee it'll be a slipping unit quite quickly.
Do you agree with that? - Yes or No? :)

No need to reply with your attitude that aligns with the almighty... I won't be here to see it as I'm leaving for some months due to conditions beyond my control... and not sure if I'll be back. (Joe)
 
I found it hard to take good pictures so I took a video instead. It seemed to me that the coils were aligned with the bevels like joereeves said, but it looks like the bevels themselves are wearing a little. Is it possible for the flywheel to be too far down and rub on those bevels?
https://streamable.com/m45ay

Also, I don't know what the inside of the flywheel is supposed to look like, but I saw these rectangles that seem to be too clean cut to be wear marks, but I was curious about what they are.
https://ibb.co/SnxSSGY
 
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I have a couple of pretty similar engines so I will try and answer your question.

I don't think it is possible for the flywheel to rub on the ignition coil mounting posts unless
the flywheel is damaged and out of round. The squares you see on the inside of the flywheel
are the magnets that energize the ignition system. I don't see any evidence of rubbing in
your pictures/video.
 
fdrgator said:
How about armature plate wobble. Does it?
Click to expand...

The armature plate feels smooth and steady when manipulating the throttle with the motor off. I haven't looked at it while the motor is running nor have I poked at it specifically with the flywheel off.
 
Just poked around at the armature plate for awhile, there's no play in it that I can detect. I did notice that the cam roller between the armature plate and carburetor does roll just a bit when it's on the downward slope even when the motor is off. Adding the vibration with motor on I can see that roller could go merrily down the slope on it's own. Perhaps flyingscott was right in that it's normal that the throttle decreases on its own. Maybe the spring is a little too tight on the cam. Maybe I need to get a new friction piece.

I just ordered a service manual, but it's going to take awhile to get here so can anyone give me the flywheel nut torque spec for 1975 Evinrude 6hp (6504)
 
OK, back to the friction plug in the twist grip: Is the spring in there too?

No it is not "normal" for it to turn itslef off. But many do beause of the stuff we've been suggesting.

Torque nut to 40-45 foot lbs
 
I noticed that the fuel line from fuel pump to carb needs replacing. It looks like it's supposed to be 5/32" id hose. Is it essential to match 5/32" or can I go a little larger to 3/16" or a little smaller to 1/8"?
 
Thanks for the update. To be honest, I don't remember ever seeing a tapered friction plug worn to the point that it didn't work any more. But after 45 years, I suppose it doesn't owe anything.
 
I'm suspicious that someone tried to put it on improperly, the tabs that slot into the metal arm were really chewed up.
 
Okay now I know what happened with Joe, I haven't been posting regularly. I pray you guys can mellow out. I respect you both.....more than you know.
 
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