1973 65hp Evinrude. I don't get it, do you?

[kyleg001]

I am hoping that someone may have had a similar issue and can help me.
I have a 65hp 1973 Evinrude outboard. I am having, for a lack of a better term, a loss of power.
When starting up the motor cold; I pull the choke put the warm up lever all the way up; and start. I then let her warm up. Warming up the motor seems to take longer than it should(always has). With the lever all the way up it runs around 2-1/2k RPM. After it warms up, the warm up lever will speed up the motor to 6K rpms. If I try shifting during the warm up, the motor dies right away.

After it warms up, I can shift OK~. When I push down on the throttle all the way till its opened up, I am getting stuck at 2-1/2K rpm.
*note this happened last season as well, but only for a few minutes at the start, almost every time I went out.
During the last season restoration of this motor, I rebuilt the carbs, replaced floats, replaced ign coils, fuel line- tank to pump, spark plugs (.30 gap), impeller, rebuilt water pump, changed fluid on lower.(ran OK~, never perfect)
Winterized by running fuel out of carbs, and used fogger.

Took her out this season and had a bunch of problems, Idle/no power (which did not go away after a few min). I then rebuilt the fuel pump; replaced rest of fuel lines, and spark plugs (.40 gap). The idle issues have been taken care of, but the motor will not raise over 2-1/2K rpms when in full throttle. The primer bulb stays firm.
Spark is good, compression even throughout cylinders ~140 or so(crappy gauge). Battery charge not monitored(could this make a difference?)

Does anyone have any clues, any help, or additional questions? I am at a loss and cannot take it to get looked at $$

Thanks in advance.

 

[jtexas]

Re: 1973 65hp Evinrude. I don't get it, do you?

Warm-up time...how long is too long? Could be thermostat stuck open (or missing) or poppet valve springs worn out. Myself, I rarely if ever try shifting before she's warm anyway.

Pretty sure it's running on 2 cylinders. Don't run it like that--if a cylinder is starved for fuel, it's also not getting lubricated.

You can pinpoint which one is not contributing with a cylinder drop test. Pull, then replace the plug leads, one at a time. Give the engine a few seconds to react. If RPM's don't change (or it doesn't die), that cylinder's not making power.

Spark test: use an inline spark tester, gap set at 7/16" clipped to the engine block. Attach the plug leads (one at a time) and look for a strong spark while cranking. If it won't spark across a half-inch gap in the open air without a plug, it's a good indication that it won't spark in the heat and compression of the combustion chamber.

If you have compression and spark, I think you have to go back into the carbs. Remove the core plugs, pull the jets, give everything a good long soak in the carb cleaner. Read the carb thread in the Engine FAQ section of iboats.

Are your carbs spitting up fuel? I don't mean just the occasional droplet, I mean really spitting it out? If so, think about pulling the intake manifold to inspect the reeds.

Use champion spark plugs. No doubt NGK makes a great plug but it's not an exact match for heat range. You need a champion Q-series resistor-type plug to avoid interference with the electronic ignition. QL77JC4 I think is your plug.

I notice you didn't mention water pump...it's not causing your current symptoms, but I do recommend changing the impeller every couple years.

 

[kyleg001]

Re: 1973 65hp Evinrude. I don't get it, do you?

Thank you jtexas,

10-15 min to long for warm up? New thermostat last year. Poppet valves didn't look to bad. Maybe I'm just impatient.

Good and simple idea on disconnecting the spark plugs, I may need to look for/borrow a DVA tester soon.

I'll have to pull the front cover off the carbs and check fuel spittage.

I'm using the champion non-resistor plugs, would that make such a large problem?(I used these last year as well)

Water pump and impeller relpaced last year.

I'll take it out tomorrow and report back.

 

[jay_merrill]

Re: 1973 65hp Evinrude. I don't get it, do you?

If you have surface gap plugs (UL77V) Champions in your motor, get rid of them. That is the originally specified plug, but the motor will run better on "J plugs." QL77JC4 plugs are fine, but you really don't need resister plugs - there is nothing on the motor that a little noise will interfere with. If it had optical ignition or something, that might be a different story, but the old motors don't have such things. I run L77JC4 plugs in mine (72 65hp, same motor except for shift type), with good and consistently reliable results.

If your motor idles at 2,500 rpm (you said 2-1/2k), it is way too high. You need to figure out why, before running it any more and you certainly should not shift the motor at this rpm. Doing so is likely to have you replacing a clutch dog soon, if not lots of other gearbox parts. The business of revving up to 6,000 rpm in neutral, is also pretty scary. I'm pretty well surprised that you didn't "eat" your gearbox, if you shifted into gear at that rpm.

The first thing that I would check is the throttle linkage. Are the carb butterflies and the timing advance (timer base) at the idle position, when your throttle is pulled all of the way back, or is in neutral, depending on what type of control system you have?

I recommend that you check that and get back to us.



???

 

[kyleg001]

Re: 1973 65hp Evinrude. I don't get it, do you?

Thank You for your input. I am currently running the L77JC4 plugs. Sorry, maybe a little clarification is needed. In netural; The 2-1/2K rpm is with the warm up lever fully raised on a cold motor. The 6K rpms is the warm up lever fully raised on a warm motor(not at idle). I try to never shift over 1.5k rpm, normally less than 1k ~900 to 800

I am currently waiting for the rain to stop. I'll see if I can get out a little later to test some ign components. Hopefully it?s not the stator or timer base I would even be ok with the power pak.
Still working out some testing procedures for these though.

 

[jtexas]

Re: 1973 65hp Evinrude. I don't get it, do you?

take Jay's advice on the spark plugs.

also the throttle linkages, I shoulda thought of that. The choke butterflies must be open (except when the choke is engaged), the throttle butterflies need to be parallel throughout their range of motion and end up horizontal (not beyond) at WOT, and the timer base needs to move smoothly without sticking all the way to it's stop.

 

[jay_merrill]

Re: 1973 65hp Evinrude. I don't get it, do you?

OK, now I get it - high rpm with the warm up lever,

Two suggestions -

You shouldn't have to warm up at 2,500 rpm. Also, your internal parts have yet to expand to normal operating configuration at this point, so over-revving the motor, is probably not a good idea.

Don't ever run your motor at 6,000 rpm in neutral. That is inviting a runaway motor and if that happens, you're going to mess up a very nice, old motor.

When you rebuilt the carbs, did you remove the three fixed, high speed orifices? If not, you could have junk in them and that would explain a smooth running engine to a certain point, but no ability to advance beyond it.

Also, did you link and sync, after you removed the carbs for cleaning?



???

 

[kyleg001]

Re: 1973 65hp Evinrude. I don't get it, do you?

jtexas, Will do on the spark plugs. The carbs open and remain parallel throughout, do not overextend at WOT.The timer base does not seem to stick.

jay_merrill, whats a good/suggested range for engine warm up? During carb rebuild; The high speed orifices were cleaned; carbs were "completely" dissembled and soaked, adjusted the individual throttle linkage to each carb so that the butterflies parallel throughout operation, and reset the cam follow to the short mark. I did not verifiy that the trimming is at 2deg at idle(is this the "sync" portion?)

-------

I just went to retest compression 120psi on all 3 cylinders(Cold). Spark is jumping a blue gap at 1/2 inch. The funny thing though, I pulled out the new spark plugs and the bottom one showed no signs of wear, it has never fired.(plugs replaced a week ago)

Something wrong with the bottom carb?

 

[jtexas]

Re: 1973 65hp Evinrude. I don't get it, do you?

See my first post "Pretty sure it's running on 2 cylinders. ... If you have compression and spark, I think you have to go back into the carbs. "

You have compression and spark.

It takes a pretty sensitive ear to tell when it's idling on 2 cylinders especially on the muffs. I was thinking maybe the 3rd cyl was kicking in eventually but now I'm not so sure.

One thing I have learned, is that the intermediate jet will fit into the idle jet hole and if you put it in there, that cylinder won't idle at all. Never tried running it at high speed like that, though.

 

[kyleg001]

Re: 1973 65hp Evinrude. I don't get it, do you?

thanks jtexas,:redface:

I'll pull the carb tonight and go through it, do I need another rebuild kit for it, or can I just use the existing parts from last year?s go through and verify correct placement of part and cleanliness.

Also, my correction from previous posts, the 3 lines coming off of the center carb that runs to the other 2 carbs do have OLD fuel line. I'll make sure to double check the high speed jet for a good sized clog.(the motor did run "OK" after the rebuild last year, I'm assuming the placement is correct, but will double check)

By Idle/intermediate do you mean high/low?

 

[jtexas]

Re: 1973 65hp Evinrude. I don't get it, do you?

I doubt you'll need new kits since you just did it last year, I'd wait & see on those.

Nah, the hi-speed jet has a bigger O.D.; if you only have 2 jets, or if you didn't remove the jets for cleaning, then disregard that last statement.

If they've started selling ethanol-blended gasoline in your area, you'll need to replace all the old fuel lines, they'll break down and foul your carbs for sure. Looks like you've already replaced all the other alcohol-sensitive components.

Otherwise if the fuel lines aren't cracked or brittle and aren't leaking, they should be ok.

 

[kyleg001]

Re: 1973 65hp Evinrude. I don't get it, do you?

Just pulled the bottom carb, the float needle is sticking. I'm off to get some carb cleaner. Any suggestions on keeping it from sticking?

What a trip, all that due to a little needle valve sticking. I try and get the boat out soon, to report if the issue is resolved. Thanks everyone for your help.

 

[ezeke]

Re: 1973 65hp Evinrude. I don't get it, do you?

Just pulled the bottom carb, the float needle is sticking. I'm off to get some carb cleaner. Any suggestions on keeping it from sticking?.......

Make sure that you have the new style needle and clip that connects the needle to the float arm.

 

[kyleg001]

Re: 1973 65hp Evinrude. I don't get it, do you?

WOW, I wish I would have seen those sooner. I'll order them right away. Thank you! I believe this is the correct one here

http://www.iboats.com/mall/partfind...gd_poid=355617&gd_row=52&**********=930191759

*Is that float level?, the metal tab on mine always seem to be slightly bent in order to level them out when they are upside down. Does this seem accurate?

 

[jay_merrill]

Re: 1973 65hp Evinrude. I don't get it, do you?

Sounds like you may have found your problem.

You definitely want to get rid of those old fuel lines. One other suggestion - put a small in-line filter between the fuel pump and the carbs. If you ever have problems with a fuel pump diaphragm going bad, it will probably keep the resulting junk out of your carbs.



???

 

[ezeke]

Re: 1973 65hp Evinrude. I don't get it, do you?

One other thing is that a lot of the engines in 1973 had an automatic choke that caused a lot more problems than it solved. The idea was abandoned and most of the existing ones were disabled.

If you find that you have more than one purple wire running to the choke solenoid, trace them back to the source and make sure that they are only operated by one controller, which should be you.

 

[jay_merrill]

Re: 1973 65hp Evinrude. I don't get it, do you?

???

 

[kyleg001]

Re: 1973 65hp Evinrude. I don't get it, do you?

Thanks for your help. Took the boat out today and it ran great. Those clips really made the difference.

Only one thing I'm still trying to get tuned in is the first(or first few) shift(s) I make after the engine warms up, will cause it to die. Also, the idle is a little high, and I?ve backed off the idle screw as much as possible, the butterflies on the carb are fully closed

There are two wire lines that run from my controls to the motor for carb/shift operation, and they do have adjustments on them, what are these adjustments for, and how do you go about adjusting them, could this be causing the issue?

 

[ezeke]

Re: 1973 65hp Evinrude. I don't get it, do you?

Before you adjust the idle screw, you get the carburetors synchronized, then adjust the cam follower roller so that it is centered on the mark on the cam, but not quite touching the cam. Then you adjust the cable to the engine linkage.

After you have all of that corrected, then you put the boat in the water in gear and make the final idle adjustment with the screw.

 

[kyleg001]

Re: 1973 65hp Evinrude. I don't get it, do you?

Got it. I did sync the carbs and adjust the roller properly, but I'll have to adjust the cable then the idle screw.

To further my question, I've been told the idle should be around 650rpm's. Does this seem accurate? I ask because when the butterflies on my carbs are completely closed the motor can idle as high as 1200-1400 rpm in neutral, and *if I shift its a steady 850-950(the roller is not touching the cam). I'll have to try and resync the carbs again, but I am fairly confident they?re properly synced. I'll report back next chance I get.