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1974 Evinrude 115 Will not start

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lizrad999

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"I've got a 1974 Evinrude

"I've got a 1974 Evinrude 115 that will not start.
I just rebuilt both carbs with all new jets, gaskets, and float valves. Rest assured, all of the orfices and pathways in the carbs have been cleaned out. I soaked the disassembled carbs in carb dunk, and blew everything out with compressed air.
I cannot see how it could possibly be the carbs. Fuel pump is working, bowls are getting plenty of fuel.
Installed new spark plugs, 100+ PSI compression on all cylinders. (Anybody happen to know the plug type and gap?)
I have resorted to spraying ether into the intake, and the engine does run for less that a second, then right back to nothing.
I've compared all of the new jets with the orfices on all of the old jets, and they are identical as best I can tell.
Seems like it's a fuel issue, but I cannot see how. I even checked the floats are level with the carbs upside down. New gas/oil, new tank and primer line.
Could the reed valves be causing this? Won't start on gas/oil, but will run on ether? PLease help? If the reed valves were bad, would I still have 120psi compression on three of the cylinders?(one has right at 100psi)"
 
"You have a compression differ

"You have a compression difference of 20 psi between the highest and lowest compression reading which is not good. I'd recommend pulling that cyl head so as to inspect the head gasket, sealing surfaces, pistons, etc.

Using ether is not a good idea as ether has no lubricating qualities. Better to use premix in a spray bottle.

Unlikely you would have four (4) reed plate leaf valves stuck open.

Did you actually replace or manually clean the high speed jets that are located in the bottom center portion of the float chambers? If not, do so as fuel must flow freely thru those jets before gaining access to any other fuel passageway.

Plugs should be Champion QL77JC4 plugs, gapped at .040 .

Spark! With the s/plugs removed, the spark should jump a 7/16" gap on "all" cylinders with a strong blue lightning like flame.... a real SNAP! Does it?

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
"My memory did not serve me we

"My memory did not serve me well. The actual compression on the cylinders ar 116, 115, 116, 120. I was working from memory...whoops sorry.

Yes, I removed the original jets, ensured there was absolutely nothing in the passageways and then installed brand new jets.

The plugs are L77JC4, so I've got to find out where the "Q" went...and I think we gapped them at .030 so I will change that as well.

I'll put together a little jig that will hold an airgap of 7/16" and test ALL of the cylinders. I made the mistake of "seeing" spark on one cylinder and assuming they were all firing....duh
Thanks for the help, I will let you know how it comes out."
 
"The "Q" simply indica

"The "Q" simply indicates a suppression type plug. The L77JC4 plug is fine, gapped at either .030 or .040, whichever works out better for you.

(Spark Tester - Home Made)
(J. Reeves)

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:


..........X1..........X2

.................X..(grd)

..........X3..........X4

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
"Is it possible that you or so

"Is it possible that you or someone else has messed with the ignition timing. It is very easy for the novice outboard motor tech to inadvertently mess up the ignition timing by turning that big screw on the starboard side of the engine. I know this from experience and my 100hp was very difficult to start after I did it.
proud.gif
"
 
"Ok, I built the spark jig you

"Ok, I built the spark jig you suggested and tested each coil. The two coils on the right sparked with no problems accross the 7/16" gap. As for the two on the left, nothing. Not one spark. I unhooked one of the right coils from the power pack, and hooked up one of the left coils in it's place. Spark.
Seems to me that ALL of the coils are fine, but half of the power pack is bad.
Is there any other tests or items I need to look at?
Would those two cylinders not sparking be enough to keep the whole engine from even firing without ether? (No I haven't used any more.)

Thanks!"
 
"Half of the powerpack being f

"Half of the powerpack being faulty is unlikely, possible but highly unlikely.

There are two timing sensors on the timer base. One fires the starboard bank, the other one fires the port bank. Check the ohm reading of those two sensors.... they should be identical. Also, check all connections and wiring of those sensors between the timer base and the powerpack."
 
"We disconnected the sensors f

"We disconnected the sensors from the power pack and tested to each with a multimeter. 7.9ohms on both of them.
olrudedude, I personally, have not made any adjustments, but that's not to say it wasn't "adjusted" the last time it was at a shop. I was given the boat and motor after my neighbors dropped it off at some boat shop for a cost estimate to fix it. The folks there said about $1500. The neighbors opted not to get it fixed, and gave it to me.

Joe, shall I order the powerpack?"
 
"If that engine incorporates t

"If that engine incorporates the rubber plug in type conectors between the timer base and the powerpack and also between the powerpack and the coils, check those connections closely.

The pins or sockets have been know to back out slightly resulting in a poor or non existent connection.

Also, the wires attached to those pins/sockets have been know to break away from the pins/sockets, BUT still remained in the rubber plug. This gives the impression that the wires are attached properly when they are not.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
"It appears there is no rubber

"It appears there is no rubber plug between the coils and powerpack, or the sensors and powerpack.
The following is a picture. The ground wire on the right did break off, but I had repaired it before any testing.


292647.jpg
"
 
"Sorry about the rubber connec

"Sorry about the rubber connector plug mention. I forgot momentarily that the engine is a 1974 model.

When you test for spark, are all of the spark plugs removed? If not, remove them and do the spark test again.

Also, the engine must crank over at least 300 rpms in order for the stator to energize the ignition.

My remaining thought is that one timing sensor is not adjusted close enough to the inner flywheel magnets."
 
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