196? 18 hp Johnson issues (need some suggestions)

[brabbit]

Took the old boat out on the river to test it out and motor ran great, wide open throttle for about 20 minutes. Stopped to fish for about 30 minutes, it fired up fine, and slowly throttled up to full and head toward the boat ramp. Five minutes in the motor started to rattle and smoke and then died. It fired back up and we traveled at 3/4 throttle for a couple of minutes and the same thing happened. Fired it up for a third time and ran 1/2 or less throttle for less than thirty seconds and it started smoking and died, this time the pull rope was hung. I got towed in and when I got home it fired back up.
I'm thinking something with the carb, any ideas or suggestions?

 

[Daviet]

Re: 196? 18 hp Johnson issues (need some suggestions)

Compression, spark and fuel delivery is what you need to make your engine run properly. Check them all.

 

[cajuncook1]

Re: 196? 18 hp Johnson issues (need some suggestions)

Did you notice if water was coming out of the exhaust relief hole (located upper 1/3 of the mid section) indicating if your impeller was functioning. There is a possibility that your motor over heated and blew a head gasket and/or locked up some.

Get your motor in a barrel and check to see if your impeller(water pump) is functioning. Water spraying thickly out of the exhaust relief hole. While your motor is running make sure it isn't over heating.

Daviet, is right, check your compression. Then your spark and then fuel delivery.

http://forums.iboats.com/showthread.php?t=313963&highlight=compression

http://forums.iboats.com/showthread.php?t=299680

http://forums.iboats.com/forumdisplay.php?f=31


If your motor overheated or blew a cylinder head gasket then your compression test will give you more information.


Oh, by the way, welcome to the forum!

 

[brabbit]

Re: 196? 18 hp Johnson issues (need some suggestions)

Water pump is fine, compression good, found fuel leaking around the lean/rich knob shaft (there is no knob on the shaft making adjustment a pain). The shaft where it goes into the carb looks like Billy Bob got ahold of it with a pair of channel locks. Probably would be a good idea to take it out and clean it up with some emery cloth, and sure won't hurt the carb to put a gasket kit in it. Know of any place to get a replacement adjustment knob?
(and the motor is a fd-15, 1961 model 18hp).

 

[tmcalavy]

Re: 196? 18 hp Johnson issues (need some suggestions)

Check the free classifieds at www.aomci.org

 

[cajuncook1]

Re: 196? 18 hp Johnson issues (need some suggestions)

Water pump is fine, compression good, found fuel leaking around the lean/rich knob shaft (there is no knob on the shaft making adjustment a pain). The shaft where it goes into the carb looks like Billy Bob got ahold of it with a pair of channel locks. Probably would be a good idea to take it out and clean it up with some emery cloth, and sure won't hurt the carb to put a gasket kit in it. Know of any place to get a replacement adjustment knob?
(and the motor is a fd-15, 1961 model 18hp).

Here is a few links for your motor. (Parts breakdown)

http://www.marineengine.com/parts/v...ntage-evinrude-johnson/378460/37846000001.htm

Breakdown of your carburetor

http://www.marineengine.com/parts/v...ntage-evinrude-johnson/378460/37846000001.htm

http://www.marineengine.com/parts/v...ntage-evinrude-johnson/378460/37846000001.htm

Type in the part number in the left hand part of the screen with parts search.

tmcalavy
Re: 196? 18 hp Johnson issues (need some suggestions)
Check the free classifieds at www.aomci.org

tmcalavy has a good suggestion if mulitple parts are missing on your carburetor, it might be cheaper to post a free Webervise want at the aomci forum to get a whole carburetor set up with adjustment linkage and nob than to buy the parts individually for a dealership. Alot the aomci.org member have parts motors and I have always walked away with a good part/s and have dealt with honest guys. Some salvage yards monitor the aomci.org Webervise site and make offers as well.

Just a suggestion. Hope you get your little lady up and going!!!

 

[Tim Frank]

Re: 196? 18 hp Johnson issues (need some suggestions)

Took the old boat out on the river to test it out and motor ran great, wide open throttle for about 20 minutes. Stopped to fish for about 30 minutes, it fired up fine, and slowly throttled up to full and head toward the boat ramp. Five minutes in the motor started to rattle and smoke and then died. It fired back up and we traveled at 3/4 throttle for a couple of minutes and the same thing happened. Fired it up for a third time and ran 1/2 or less throttle for less than thirty seconds and it started smoking and died, this time the pull rope was hung. I got towed in and when I got home it fired back up.
I'm thinking something with the carb, any ideas or suggestions?

If that means what it sounds like, your motor seized ....likely from overheating or oil shortage.
Was there water pumping? What mixture (oil/gas) are you using.
Is this rig new to you?

 

[outlaw241]

Re: 196? 18 hp Johnson issues (need some suggestions)

i agree sounds like overheat issue if you pull the head to change head gasket make sure to check that head is still flat an not warped

 

[cajuncook1]

Re: 196? 18 hp Johnson issues (need some suggestions)

Brabbit, is this old motor new to you? Water coming out of the exhaust relief hole means that the water pump is working......it 100% doesn't mean that it is cool the engine head.

- Sometimes sand, salts, and impurities build up in the passageways going to the head and water is not circulated to the head to cool it off.

- A plastic bag could have occluded to water uptake at the foot and while cruising along over heat the head and blown a head gasket, scuff up the piston, rings and cylinder. (The bag comes off when the boat stops and the culprit is not found)

(I am not saying 100% that your motor overheated...but the symptoms you describe are similar.)

Tim Frank brought up a excellent point.....what gas oil ratio are you using?

You should use 24:1 ratio with your motor. (50:1 ratio is not enough lubrication for your motor and should not foul up your plugs). Not enough oil will cause premature death of the motor.

A good investment and a piece of equipment that will give you peace of mind is a laser digital thermometer that you can get at Harbor Freight and other places of that sort for about $20 to $30 dollars. You can measure the temperature of the heads on side and near the sparks plugs (basically around the cylinder head).

**Some people say that you if you can hold your hand to a cylinder head for about 3sec then you should be ok......Well to me that is not a 100% reliable method, because we all have different heat tolerance of touch. I'll tell you 140 to 150degrees feels hot to me, but it is acceptable running temps. Best bet is just to get a temp reading with the old temp sticks or a laser digital thermometer....(they or cheap enough for a peace of mind and they can also be use to measure the temperature of cooking oil when frying a turkey(but that is another story).***


The thermostat(T-stat) partially opens around 135 to 140 degrees and is fully open around 160 degrees. The thermostat opens and allow water to circulate around the water jackets around the cylinders to maintain temperatures less than 163 degrees.

Exhaust relief hole or water indicator that is expelling or discharging water is an indicator that your water pump/ impeller is working only. It does not mean that your engine is properly being cooled and water is circulating around and through the water jackets.

Things that can cause an powerhead to over heat even though you have a good stream of water coming out of the exhaust relief hole or water indicator.

1. Stuck or obstructed Thermostat from salts, to junk, gunk and sand. Just bad T-stat

2. Obstructed passage to the cylinder heads caused by foreign material (bits of an old impeller), salts, and sand. (Obstructed water tube near power head or distorted water tube gromet)

3. Sand, salts or foreign material occluding the water jackets prevent water from circulating around both cylinders.( This happened to me and I removed the the cylinder head and cleaned out the passage ways and a new T-stat. My Evinrude 6hp was back in business)

4. Swollen water deflectors in larger motors and can be caused by an overheating situation. (these are never mentioned in service manuals)

5. Blown head gasket between cylinders that allows heated compressed air in the water jacket systems and prevent water from circulating.

6. Lean carburetor adjustment and not enough lubrication to inside the cylinders, pistons and rings.

If your engine is primarily used around salt water or sandy environments then chances are that statements 1, 2, or 3 are a high possibility. (So flush your motor well after a salt water run with fresh water)

If the motor is used but new to you, any of the situations could apply.

Again....not saying my suggestions are 100% correct.....just throwing out suggestions based on information given and an assumption.

 

[brabbit]

Re: 196? 18 hp Johnson issues (need some suggestions)

Running 50:1 fuel ratio (thought that is what the manufacturer recommends for this model motor at least that is what I have read, just read on one post that up to 63 should be running 24:1!!!), water pump is and has been pumping (motor staying nice and cool), the pawl on the pull rope assembly is worn and "mashed out" causing it to hang up. Fired it up in a barrel last night and ran it for over half an hour, and stayed cool on the head. I am convinced that it did not overheat and that 99% of my problems are with the carb. My dad bought a "nicer" boat this year and did not have room for this one too at his house, but he did not want to sell it. Since my ski boat is down for a major rebuild I offered to store it for him and keep it in good use. He had ran the motor for about two years and turns out (after talking to him last night) he has had issues with the carb.

 

[cajuncook1]

Re: 196? 18 hp Johnson issues (need some suggestions)

Water pump is fine, compression good, found fuel leaking around the lean/rich knob shaft (there is no knob on the shaft making adjustment a pain). The shaft where it goes into the carb looks like Billy Bob got ahold of it with a pair of channel locks. Probably would be a good idea to take it out and clean it up with some emery cloth, and sure won't hurt the carb to put a gasket kit in it. Know of any place to get a replacement adjustment knob?
(and the motor is a fd-15, 1961 model 18hp).

Well the reason I stated 24:1 fuel ratio, because you stated that you had a 1961 18hp Johnson.


This information was copied verbatim from a OMC (Johnson/Evinrude manual)
OMC12-20HP OLD OUTBOARD MOTOR
EVINRUDE, GALE AND JOHNSON
12, 15, 18 AND 20 HP

Carburetor
Make
Fuel?Oil Ratio?Before 1964
24:1

Fuel?Oil Ratio? After 1964
50:1

Well, I am certainly glad to hear that it is the head is cooling ok. You can ignore all the crap I posted about head cooling then. I guess you just need a good carb job and kit. The question about where to get a slow idle needle is list above in one of my enteries with the link for it and you can also get a replacement starter prawl as well. You might want to lube your starter spring it might have old thick drying grease in there.

If you do a carb rebuild with a kit, remember to remove the core plugs and clean everything out well. remove the old slow needle packing, because the old packing gets partially dissolved by the carb cleaner and also when they get old, they allow air in and mess up your fuel to air mixing fine tuning. Use that new packing that comes in the kit. Make sure you level your float as described in the links listed below.

Here is the forums link to carb cleaning and another link for adjusting your carb slow idle needle.

http://forums.iboats.com/showthread.php?t=244013

http://forums.iboats.com/showthread.php?t=167352

Hope you get your motor fix soon!!

 

[brabbit]

Re: 196? 18 hp Johnson issues (need some suggestions)

I appreciate the help. My old man and the owner before him had been running a 50:1 mix on the fuel, I'm sure some damage has already been done so I bought a brand new trolling motor for a back up when on the river. Thanks again.