81 35hp johnson white smoke and stuttering

borro

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Joined
Apr 12, 2004
Messages
7
I have a 81 35hp johnson electrical start. (J35ELCIG) Last year it died whilst running (not a full block but just stopped firing) and it turned out that the nipple holding the water drainpipe on the engine had broken of. So I suspect that it either overheated or the electronics got wet. I have the engine running again, but it does not run steady and it produces a lot of white smoke (or steam?). If I turn the carburetor knob to rich it keeps running (although not smoothly) if i turn it leaner it starts to backfire and especially when i throttle it up. The two holes on the back of the tail (what are they called?) sputter water and on revving it up it sounds like steam explosions (hissing sound). The spark plugs looked reasonably okay after letting it run for about half an hour (dark, little wet with fuel). I will check the compression and post the results over the weekend but was wondering if anybody has any clues on this with this information. My first thoughts were on a faulty ignition timing, however i don't have a clue on how to check that.
 

Hooty

Rear Admiral
Joined
Oct 2, 2001
Messages
4,496
Re: 81 35hp johnson white smoke and stuttering

Hmmmm.<br />I'm guessin' the the "water drainpipe" is the tattle tale and when the nipple broke it hosed everything under the cowling, including the electronics. They should all be okay after they dried out unless something shorted when it got wet. The timing is probably okay because it can't change by itself. Do you have a manual for the engine?<br /><br />c/6<br />Hooty
 

borro

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Joined
Apr 12, 2004
Messages
7
Re: 81 35hp johnson white smoke and stuttering

nope i don't, i ordered one though :) figured it might help... I'll post the compression numbers once i've measured them. I want to rule a possible blown head gasket or piston rings out.
 

OBJ

Supreme Mariner
Joined
Dec 27, 2002
Messages
10,161
Re: 81 35hp johnson white smoke and stuttering

Welcome aboard iboats borro...<br /><br />Question...while running the engine, was the bock so hot you couldn't touch it? There's a flat place on top of the block just forward of the head. At idle, you should be able to lay your fingers there for several seconds before having to remove them.
 

borro

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Apr 12, 2004
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Re: 81 35hp johnson white smoke and stuttering

tnx obj, a great site it is! lots of knowledge here :) <br /><br />I'll try the test with the fingers tomorrow when i've got time to look at the engine again and'll let you know. From what I can recall it didn't run too hot, but i'll have to retest.
 

Dan McCosky

Recruit
Joined
Apr 11, 2004
Messages
3
Re: 81 35hp johnson white smoke and stuttering

Sounds like your thermostat is stuck closed.
 

borro

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Joined
Apr 12, 2004
Messages
7
Re: 81 35hp johnson white smoke and stuttering

I did a quick compression test yesterday and both cylinders had 100 psi (98 top and 96 bottom). I'll try the hand on the top of the cylinder test today. <br /><br />How can I check the thermostats functioning dan?<br />and where can i find it? (it'll take two weeks for the manual to arrive :( and i would like to be in the water before that, spring has started here...
 

borro

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Joined
Apr 12, 2004
Messages
7
Re: 81 35hp johnson white smoke and stuttering

I tried running it and putting my hand on top of the cylinder, but it was way too hot, so something with my water supply. Can anybody somehow explain where i can find my thermostat? I could test how it works without.<br /><br />Tnx for the help so far!
 

dragula65000

Petty Officer 2nd Class
Joined
Apr 14, 2004
Messages
180
Re: 81 35hp johnson white smoke and stuttering

It definantly sounds like a thermostat problem. Most likely when the water got in there, it shorted a wire out, or the thermostat had a moment all over itself. But where to find it, I'm not sure. Try to find a wire thats pressed into the cylinder head, or around the bottom of the motor. Thats about all I can say.
 

saffi

Seaman Apprentice
Joined
Oct 2, 2003
Messages
44
Re: 81 35hp johnson white smoke and stuttering

Hi there,<br /><br />The thermostat is behind the cylinder head cover (on the top). I can give you adresses of places to buy a thermostat and gasket etc. if you want. (I bought one a week ago). Greetings from sunny Amsterdam.<br /><br />Saffi
 

borro

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Joined
Apr 12, 2004
Messages
7
Re: 81 35hp johnson white smoke and stuttering

Saffi, <br /><br />If you could give me the address that would be grand, i was afraid i had to mail order stuff from the states cause all i've heard from the dealers etc. so far is that parts for these kind of engines are not available anymore out here...<br />but u say they are :) <br /><br />p.s. u r all helping with getting tfb into the water: http://borro.xs4all.nl
 

saffi

Seaman Apprentice
Joined
Oct 2, 2003
Messages
44
Re: 81 35hp johnson white smoke and stuttering

I also had problems finding thw spares (I have the 25HP '82 model, almost identical I think). It is just a bit cheaper to buy the parts from the US but delivery takes up to four weeks and shipping can be very expensive. I order the spares from Renautic in Haarlem. Nice people and they also have lots of used parts. They order from Sierra or OMC. You can find the sierra catalogue here: http://www.abcjb.com/sierra_catalog.htm <br /><br />The thermostat is OMC 434841 or Sierra 18-5709 I think. Shouldn't be more than 15 euro's including the gasket. I also list another place in Amsterdam. Oranjemarine never returned my e-mail but they do have a shop and have a lot in stock. I use the Seloc 1971-1989 Johnson/evinrude outboard guide volume 2. Bought from Amazon.<br /><br />Renautic<br />Lagedijk 1 <br />2065 AP HAARLEMMERLIEDE <br />Netherlands <br /> <br />Telefoon<br />023-5310790 <br />Fax<br />023-5340134<br /><br />Oranjemarine BV<br />Nieuwendammerkade 28 <br />1022AB Amsterdam<br /><br />Tel: 020 6341202 <br />Fax: 020 6328316<br /> <br /><br />Nice boat by the way. Hope to see you around the canals soon :) <br /><br />greetz, Saffi
 

borro

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Joined
Apr 12, 2004
Messages
7
Re: 81 35hp johnson white smoke and stuttering

Tnx saffi, I've called them and should be able to work it out with them.<br /><br />Honk your horn if you see me on the canals this summer (she'll bear the name TFB), I owe you a beer.<br /><br />Of course that goes for all of you, but 'cause of location saffi is the most likely person to run into :) <br /><br />Big big tnx to all, you saved me buying a new(er) engine!<br /><br />B
 
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