Should I be cautious on this engine?

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NJCoastFlyFish

Petty Officer 3rd Class
Joined
May 22, 2005
Messages
92
I am going to take a look at this engine, it is a 1986 evinrude 70hp. Motor has no problems EXCEPT cracked emulsion tubes (tubes that pick the gas up to the carbs) that cause the engine to run ruff, it's compression it also around 80 on all cylinders. Would these bad carbs somehow cause unusaly strain on the engine, or is it not that big of a deal?<br /><br />I don't know what to make of this, if I put new carbs on will the engines compression go back to normal (I think around 100)
 
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phatmanmike

Captain
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Oct 24, 2003
Messages
3,869
Re: Should I be cautious on this engine?

carbs do not make compression. they have nothing to do with each other<br /><br />check for a nother engine
 
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rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Should I be cautious on this engine?

thats a new one on me. I guess its possibvle. usually cracked emulsion tubes just cause a loss of power at high speeds. mostly the emulsion tube problem was on the minlon bodied carbs. have it checked out. I think the only way to fix it is carb replacement. maybe dHadley has a better solution.
 
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NJCoastFlyFish

Petty Officer 3rd Class
Joined
May 22, 2005
Messages
92
Re: Should I be cautious on this engine?

Hey guys, is 80psi way to low on this engine? I just thought that it is that way because of age but I don't know what there PSI should be, I was thinking 100. If all cylinders are showing the same PSI I would think there is nothing wrong with the heads, but please corrct me if i'm wrong! He said he just had the whole thing serviced by a mechanic, that is how he found out about the emulsion tubes. He said the emulsion tubes make the motor run ruff at idle and sometimes makes it tricky to shift. <br /><br />I am just looking for an outboard to use a season or two before I am in the position where I can afford a new one, and he is offering this one fairly cheap.<br /><br />Also if you have followed my other posts "what outboard to pick" it has been a nightmare trying to find a decent used engine for the right price. Someone tried to fraud me on ebay as posing as a seller of a yamaha 90hp so that didn't work, and then I drove over 400miles saturday to pick up an evinrude I thought I had already bought only when I got there was told it was sold the night before, but he forgot to tell me! No luck
 
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djzyla1980

Chief Petty Officer
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Jul 26, 2005
Messages
640
Re: Should I be cautious on this engine?

No expert..... but I believe that as long as there even it should be ok. If you get it you might try a decarb on it as this may bring the comp up. <br /><br />Not sure on the emulsion tubes tho. Carbs will only effect the gas getting to the cylinder. <br /><br />If the motor was cheap enough....and seemed to run good (understanding cracked tubes) I would grab it. see how it does for a bit and then if all goes well look for some used carbs. Just depends on what you want to spend.<br /><br />Another thing. New or old motors can have probs. The guy could have told you everything was fine but he didn't. He told you what was wrong. At least you would go into this motor knowing there is and could be more probs. <br /><br />Might end up with a really great motor....that just needs decarbing and a set of carbs, but on the other hand you could end up with a money pit.<br /><br />My deciding factor would be how much the motor cost is.
 
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Goodoleboy

Chief Petty Officer
Joined
Nov 20, 2003
Messages
555
Re: Should I be cautious on this engine?

I doubt that all cylinders have exatly 80 pounds each. <br /><br />If it were me I would squirt some wd40 into each cylinder and let it set for 30 minutes or so. <br /><br />Then useing a known to be good compression gage run a new test.<br /><br />With throttle wide open, all plugs removed, spin motor for a count of 5 seconds on each cylinder.<br /><br />Use a compression tester with a screw in type adaptor. Not one of the old rubber tiped jobies. <br /><br />If you can get it above 100 pounds and not more than 10 pounds diff. in all cylinders.<br /><br />Then mabey I would think about offering uh few bucks for this engine.<br /><br />If it wont come up to these numbers. I would touch it with a ten foot pole.<br /><br />Your gona spend 500 or more just for carbs. If you have to rebuild power head your looking at another 1000 just for parts and machening.<br /><br />Even if you do all the work your self. your looking at 1500 dollars. If you have a marine shop do it. your gona spend close to 2500 to 3000.<br /><br />Iam not trying to discourage you, I just thought mite wana know before you start.<br /><br />Good luck!
 
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NJCoastFlyFish

Petty Officer 3rd Class
Joined
May 22, 2005
Messages
92
Re: Should I be cautious on this engine?

Good point, I might want to do a compression test again.<br /><br />I figure I wouldn't go compleately all out for new carbs, I would probably pick up carbs from a 70hp junker that are in reasonable shape. <br /><br />And the cylinders don't have 80 each, I think he said they were all 85-90 and the middle cylinder was scuffed up when he looked at it, also the comp readings were done a year ago and the engine has been sitting winterized since then. Among other things, the carbs with the cracked emulsion tubes were rebuilt despite the cracks, it got a new powerhead in 1988 and the lower unit was just resealed. As well as the usual stuff, new water pump impellar, the tilt was rebuilt, the starter was rebuilt, this was a high hour motor, you can tell, but it also received a decent amount of parts. <br /><br />And as for price, he said $500 but would let it go for cheaper, i'm thinking $400 or $350 if i'm lucky
 
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G DANE

Commander
Joined
Nov 24, 2001
Messages
2,476
Re: Should I be cautious on this engine?

Take my advise and do your own investigations. I've heard a lot of: It ran fine when it was put away for winther. It just needs an impeller job. Mechanic told me all it needed was new spark plugs. Its just been serviced a.s.o. Unfortunetely not all people are being honest, some try to pass on a problem. You cant do a realistic comp. reading on a wintherized motor, the fogging oil will raise compression.
 
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seantim

Seaman Apprentice
Joined
Jul 21, 2005
Messages
48
Re: Should I be cautious on this engine?

i hope its ok to post this if you buy the engine i have a perfect set of carbs for $75 fresh clean and have tried them on my engine i like them better than mine because they have idle adjustments
 
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rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Should I be cautious on this engine?

the oil and wd 40 tricks are an absolute waste of time. period. will tell you absolutly nothing of the cylinder sealing. <br /> if the compression is within 10 PSI on all its ok. aint no way two strokes will wear evenly. once one set of rings allows blowby the motor fails soon after.<br /> emulsion tube have NO effect on idle quality.<br /> they will affect the atomization of the airful coming from the main jet, however they have no effect on idles as no fuel flows from the emulsion tube at idle. seems some one is poofing smoke up the rumpus or someone just has no clue.<br /> and rebuilt to some means Rusty bolt Bob and his can of crylon worked on it.
 
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NJCoastFlyFish

Petty Officer 3rd Class
Joined
May 22, 2005
Messages
92
Re: Should I be cautious on this engine?

Seantim shoot me an email<br />Saltfli@aol.com<br /><br />Yeah I suppose I could be getting smoke blown up my (you know what) but I think he is just telling it as he knows to the best of his knowledge. Sounds like a good guy though, it's just tough sorting through an engine like this with so many what if's and maybes, i'm beginning to think this engine just won't last another season, I don't know, but anyway I think the best thing is if I go and take a look for myself
 
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