1986 evinrude 140 question

[Joe Reeves]

Re: 1986 evinrude 140 question

Greg... You say "it does not have a steady idle, it moreless fluctuates".

A slow rpm roll up and down could be caused by a fuel/air leak at some point between the fuel pump and the fuel supply.... OR by having the linkages between the carburetors not synchronized, that is having one butterfly ever so slightly open in relation to the others.

A microsecond interuption (popping, spiting back) is usually caused by a fouled or lean setting carburetor as mentioned previously.

A sudden instantenous drop in rpms, and a later just as sudden and instantenous regain of those rpms has always proven to be an ignition problem. I've never encountered a powerpack to be the cause of this type problem. This is usually due to a failing coil, spark plug, something of that nature.

S/Plugs should be Champion QL77JC4 plugs, gapped at .040. Check the continuity of the plug wires and coils as follows.

(Magneto Capacitance Discharge Coils - Continuity Test))
(J. Reeves)

Check the continuity of the ignition coils. Remove the primary orange wire from whatever it's connected to. It may be connected to a powerpack screw type terminal, a rubber plug connector, or it may simply plug onto a small boss terminal of the coil itself.

Connect the black lead of a ohm meter to the spark plug boot terminal, then with the red ohm meter lead, touch the ground of the coil or the powerhead itself if the coil is still installed.

Then touch (still with the red lead) the orange wire if it's attached to the coil, or if it's not attached, touch the primary stud of the coil. You should get a reading on both touches (contacts). If not, check the spring terminal inside the rubber boots of the spark plug wire. Poor or no continuity of a coil is one reason for s/plug fouling.

When time permits, visit my store (copy/paste) at: stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

 

[gregr1971]

Re: 1986 evinrude 140 question

going out to do that now, thanks joe, i will report back my findings.

 

[gregr1971]

Re: 1986 evinrude 140 question

ok, all checked out! no different.
i am leaning towards a lean condition??? with the airbox off, idling, when it coughs, a flame comes from the top port carb. ??? i have sat the carbs up to oem specs, 1/32" above the gasket flange for the float drop, i am still curious as to if i have the air bleeds in their correct location.??

 

[gregr1971]

Re: 1986 evinrude 140 question

could the carbs be in the wrong spots????

 

[flabum]

Re: 1986 evinrude 140 question

Are you sure the spaghetti seal behind the carb is good and in place properly? Did you replace the side cover gaskets? Take a look into the carb throats and inspect the reed valves.

 

[Joe Reeves]

Re: 1986 evinrude 140 question

A flame comes out the carburetor throat? That will happen only if a reed (leaf) valve related to that particular carburetor is not seating properly, is sticking open, cracked, or has a piece broken off.

You're probably already aware of this but for those that may not realize...... Those carburetors feed in a "X" pattern. That is, when in the boat facing them, the carburetors on "your" left feed the opposite side of the engine and vice versa. Notice the carburetors alignment height. Top carb is #1 cyl, Next down #2 cyl, next down #3 cyl, bottom carb #4 cyl.

When time permits, visit my eBay store (copy/paste) at: stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

 

[gregr1971]

Re: 1986 evinrude 140 question

i replaced it all, and as far as the seal, i use grease to hold them on, yes, they are on corectly.
i use only the omc parts, so there is no confusion on the parts.

Are you sure the spaghetti seal behind the carb is good and in place properly? Did you replace the side cover gaskets? Take a look into the carb throats and inspect the reed valves.

 

[gregr1971]

Re: 1986 evinrude 140 question

Joe, i have pulled that section off the engine 3 times, 2 of them were today, to inspect the reeds, i had the same thought. all of the reeds are sealing.
one thing that comes to mind, isn't there a magnetic ring on the center of the flywheel for the timer?? if so, if so, if the ring were cracked, wouldnt it cause it to run erraticly??

A flame comes out the carburetor throat? That will happen only if a reed (leaf) valve related to that particular carburetor is not seating properly, is sticking open, cracked, or has a piece broken off.

You're probably already aware of this but for those that may not realize...... Those carburetors feed in a "X" pattern. That is, when in the boat facing them, the carburetors on "your" left feed the opposite side of the engine and vice versa. Notice the carburetors alignment height. Top carb is #1 cyl, Next down #2 cyl, next down #3 cyl, bottom carb #4 cyl.

When time permits, visit my eBay store (copy/paste) at: stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

 

[Joe Reeves]

Re: 1986 evinrude 140 question

The center ring on the flywheel is a two pole magnet that actuates/causes the timing sensors to emit an (approximate) 1.5 volt signal to the SLR switches of the powerpack(s). And yes, if that ring should melt down slightly, it's unlikely that the engine would run at all BUT if it did, it should affect all cylinders identically, not affect just one.

The same holds true should the flywheel key be slightly sheared. If the flywheel has been off, make sure that the nut is torqued to factory specifications. Anything less than factory specifications will result in a sheared key.

To have a flame shooting out the carburetor throat, either the reed leaf valve is somehow faulty as mentioned above OR the engine is firing out of time for some reason OR the related piston is damaged to a point that the combustion is firing back into the intake port, something of that nature.

Frankly I have never encountered a condition whereas a flame would actually be shooting out the carburetor throat but the above explanation seems logical to me.

 

[gregr1971]

Re: 1986 evinrude 140 question

i also pulled th heads and replaced them with the factory heads,and now my compression reads around 118-110psi.
pistons and cylinders look excellent.

 

[flabum]

Re: 1986 evinrude 140 question

Top port carb....#1 cylinder. Pull your flywheel and take a look at the top seal. sometimes the stator will melt goo onto the seal causing an air leak that will cause that cylinder to run lean. Also check for crankshaft side play.

 

[gregr1971]

Re: 1986 evinrude 140 question

flabum, that was one of the first things i checked, i am officially lost!!
i have a good mind to go and run it as is, to see what happens.?
i have the 200, but i dont really want to put it on a flats boat.

 

[gregr1971]

Re: 1986 evinrude 140 question

i also set my spark tester to 7/16", all cylinders have a consistent ,hot blue snappy spark.

i am going to pull the flywheel again in the morning and doublecheck the seal and look at all of the magnets again in the center, the outer ones seem to be screwed on.

 

[flabum]

Re: 1986 evinrude 140 question

The outer ones are screwed on because someone put a kit on it, helps keep the magnets from comming loose.

Do you know if those reeds ever been off? The reason I ask is that there was a service bullitien way back when concerning the reeds. Seem the Mexicans that were assembling those were dipping the reed screws into the permatex and creating a hydro-lock not allowing the reeds to be properly tightened to the manifold. the gaskets would eventually blow. Pull a reed screw on that cylinder and look for black permatex on the end of the screw.

 

[gregr1971]

Re: 1986 evinrude 140 question

WOW! i am going to wear out the threads on those bolts!! i will pull them off again, but i guess i will go ahead and order some boyesen power reeds since it will be apart AGAIN! when i get the reed block off, i wil post some pics of it.

i replaced all of the crazy routed fuel lines, do they need to be equal length??

i also put a new fuel pump on it, but this one does not have the provision, nor the sensor for the oil line????

 

[Joe Reeves]

Re: 1986 evinrude 140 question

As a thought, not that it would cause a flame to shoot out a carburetor, BUT check the recirculating valves that exist in the forward side portion of the crankcase.

Pressure should flow ONLY from the inside screened portion towards the needle shaped outside portion. If a valve is faulty, pressure would flow in both directions. Should this condition exist with any one valve, one cylinder would run rich and another would run lean.

 

[gregr1971]

Re: 1986 evinrude 140 question

i wil do that as well, i did have an issue with those same valves on my 200.
it is acting as if the timing is way off, how do i adjust it ?? i have the knob on starbord, just does not realy change it much, if any. wrong timer maybe??

 

[gregr1971]

Re: 1986 evinrude 140 question

ok, all of the reeds are tight, the stops are tight with no silicone on the screws, top seal is good, no side play or vertical movement in the crank.
but the ring in the center of the flywheel is cracked in 2 places???
i pulled the powerpack off and the ground wire was only hanging on bt one or two strands of wire, re soldered it but there is corossion on the wire and leading into the insulation, so i will replace it. as for the ring on the flywheel, is it replaceable??

 

[Joe Reeves]

Re: 1986 evinrude 140 question

Are you sure about those two cracks in the center magnet area?

If that magnet area has entered a melt down scenario, that would be obvious, however.........

That center sleeve has two slots in it. Those two slots are the positive pole and the negative pole magnets. Do not mistake them for cracks.

 

[gregr1971]

Re: 1986 evinrude 140 question

Joe, how can i be sure it has not gone into meltdown??