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1977 johnson 140 no power under load

G

gizmolvr

Contributing Member
have a 77 johnson 140 installe

have a 77 johnson 140 installed on an 18' center console. Took it out yesterday and the boat would not go over 10mph and the rpms would not go over 3500. Once in a while the motor would "kick in" and the rpms would go up and the boat would start accelerating as it should and you could feel the power was there. I tried 3 different props but since it would occasionally "kick in" i dont think that is the issue. Compression is good. I am assuming that I am not getting spark to one of the cylinders or the power pack is bad. Any ideas?
 
"just had similar problem with

"just had similar problem with V4 ,fauly power pack.Yours may be on the way out. feels like loosing half of the engine,smells rich,wont rev.
pull plugs and check condition."
 
It did start to smoke a little

It did start to smoke a little as it was running too rich and would not rev under load. What exactly should i be checking
 
"Compression is good? What is

"Compression is good? What is the compression readings of all cylinders by number? Standing in back of the engine, facing the spark plugs, the cylinders are numbered as follows:

2...1

4...3

Remove the spark plugs and do a spark test using a tester where you can set a 7/16" gap for the spark to jump. The 7/16" gap is important. The spark should jump that gap with a strong blue lightning like flame.... a real SNAP! Does it?

No tester? Here's one you can build cheaply.

(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

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

Let us know what you finnd."
 
"Follow Joe's advice, espe

"Follow Joe's advice, especially the homemade spark tester - its helped me out more than a few times in the past. Also buy a compression meter from your local auto store - only a couple of bucks but worth its weight in gold as you will know for certain whether or not the compression is good or bad

Also remember the following sequence:- pump, squeeze, bang, pop.

Pump is for fuel delivery and covers everything to do with fuel (lines, carbs etc.)
Squeeze is for the all important compression and the means of getting it (pistons, rings etc.).
Bang is for ignition systems (timing, plugs, etc etc).
Pop is for exhaust - are the exhaust gases getting out the correct way.

You have to have all of these in the right quantity, quality and order to get things to work.

I had similar problems with my 79 140 last year and with the assistance of Joe Reeves and Morten Ringvold found a multitude of faults including cracked coils and dirty powerpack connectors causing poor ignition, and finally a clogged carb float needle valve (though that last one was for loosing power after being at high revs for a short time as the carb couldn't deliver enough fuel demanded by two of the cylinders).

My engine has been starting and running better than at any time I've had it since these two talked me through the problems (until yesterdays minor fuel leak, but JWBMarine has allready given me the part number I needed)."
 
"checked compression, 115 on a

"checked compression, 115 on all cylinders. Did the spark test, found no spark on bottom left cylinder(looking from back of boat). I plan on replacing the powerpack and while at it the coils. I also found that the transom plate lists the model number as a 1977, the power head definately isnt because the 1977 has one power pack and my powerhead has 2. I believe the powerhead was swapped out at sometime. The only number i could find on the powerhead was on a small siler circle on the top left of the head- 392758RPH. Is the any way can determine what year the powerhead is? Any locations to look? thanks for the help"
 
any help would be greatly appr

any help would be greatly appreciated. The powerpack/coils i received do not look like the ones currently on the engine. Is there any other way to identify the powerhead?
 
"do u have a primer,or a choke

"do u have a primer,or a choke,...primer has hoses and squirts fuel,..choke,has flappers on carbs...primer was in 81....so if u have that,..i would say 81 or ltr....can u post a pic,..i bet we can guess it....edumacated guesstimation."
 
"i just saw the RPH......that

"i just saw the RPH......that stands for ----reman powerhead......which,...is a good thing...."
 
i believe it is choke. Push th

i believe it is choke. Push the key in it activates a small motor on the power head that opens or closes the flaps.
 
"Dual powerpacks? Check the pi

"Dual powerpacks? Check the pins and sockets and their attached wires within those rubber plug connectors. THey have a habit of getting pushed back (poor connection) or having the wires break off from the pins/sockets.

What is the number listed/imprinted on your original powerpack?

If able, show pictures of your original powerpack and coils here..... along with the new ones you received if you still have them.

If you have a problem listing pictures here, attach them to a email to me. Click on my name to the left for my address. Various pictures of the engine in general would also help."
 
The powerpacks currently on th

The powerpacks currently on the engine are # CD4 581805 . I ordered the replacements for this oe # and got CDI 113-2125. The part #'s were worn out on the original coils. I should be able to post pics of the engine tomorrow. Thanks for all the help. Is there anything else i should look for to determine the year of the powerhead?
 
"John.... The powerpack number

"John.... The powerpack numbered 581805 supersedes up to part number 582125. This is a powerpack that is also used on many 2 cylinder models.

The original coil, part number 581998 (yours) has been superseded many times in numbering and also in its design. From 581998, it superseds up thru 582330, 582336, 583737, and finally to 584561. This latest coil is completely different in appearance and has the push on spark plug type connector at the coil just as on the spark plug end. The white numbering on the coil is usually 582106.

Your engine, pertaining to the year. The only engine in the V4 range that has the dual powerpacks and the electric choke butterfly setup is the 1979 year.

The 1978 model has just one powerpack. The 1980 model has a fuel primer solenoid instead of a electric choke.

Bottom line.... your engine is a 1979 model. Now, if your engine has a bubble type exhaust baffle plate (large plate between the cylinder heads), the engine is a 140hp model. Let us know.

When time permits, visit my eBay store at: http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
"Joe, thanks for your response

"Joe, thanks for your response. Is the plate what you see if you are looking from the back of the engine? There is a large cover that is bolted on inbetween both cylinders.I will take a few pics and post tomorrow"
 
"John.... Yes, that's the

"John.... Yes, that's the plate I speak of. If it is flat, it is either a 85hp, 100hp, or a 115hp model.

If it is not flat but rather protrudes back towards the hood (bubble plate), it is a 140hp model."
 
"Thanks for all the help. I re

"Thanks for all the help. I replaced all the coils and the 2 powerpacks today. I am now getting spark on all cylinders and the motor seems to be running smoother. I will be taking it out on sunday for a sea trial, will let you know how it goes....thanks"
 
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