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    random misfire

    I figured out an intermittent misfire on my 70hp omc last year. Just thought I'd share my find.<br /><br />The connections on the powerpack to the sensor coils were oxidized. Not really visible corrosion, but just a darkened appearance. First time I 'fixed' it I just wiggled the wire then...
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    low compression 70hp omc

    I just reringed my 77 model Johnson 70hp. It runs great on the muffs although the idle seems lean[no smoke and white plugs after an hour of running]. It smokes real good when you romp on it. Just for grins I checked the compression with a known good gauge. 80psi on every cylinder. It had...
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    470 to 350 swap?

    I've seen 4 bangers get swapped for v8's before. I have a nice set of v-8 manifolds from an old Chris-Craft and will be buying an 19ft v-hull with a 470 merc in a few days. I don't need to hear 'it can't be done'. Just wondering what snags I will run into. Mostly I'm worried about the crank...
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    transducer mount

    Currently my transducer for the fishfinder is mounted outside the boat. I'd like to know if epoxying it to the floor would work just as well. Where its at now I get false readings in shallow water and high speeds. Would a floor mount help this? Also what kind of glue should I use?
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    dual outboards

    I have a 15 1/2 foot trihull that seems very heavy. Current engine is a 70 hp evinrude that runs fine. I had a complete spare johnson 70 that I overhauled last winter. Would it be feasible to mount both on the back of my 85hp max rated hull? If so where could I find a cheap bracket or would I...
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    OMC gaskets?

    I just tore down a '89 model 350 Chevrolet..er omc in need of a valve job. Will standard fel-pro gaskets be fine? Reason is the gaskets on there are very strange looking to this auto mechanic. I am afraid of long term corrosion affecting the fel-pros. Also the leaky intake valves on 5 and 8...
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    porting 70 johnson

    I have a spare powerhead in need of a ring job. It's a 1977 70hp johnson. I have some experience with porting 2 strokes and I'm an auto mechanic for a living. I'm just wanting some guidelines on port height/shape to increase power in the midrange. Durability is important and I don't want to rev...
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    rollers

    I just bought a dilapidated trailer. My original Dilly trailer never has fit my 15' Invader trihull. The broken dilly spring was enough to make me want something better instead of fixing it. I got this trailer real cheap because the crossbars were bent. I welded some 3 in. channel with corner...
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    exhaust flow

    Reading from this forum made me wonder... I noticed a difference in a couple of props for a '78 OMC 70hp. One has much bigger exhaust holes in it. More than double the size. Would this make a difference in power or is there a restriction somewhere else?
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    old seized motor

    Me and a friend just went halves on a boat with a '78 Evinrude 70 horse. We finally got it freed up after lots of oil and removing the lower unit. The cylinders appear to have rust coming out of them. We've cleaned the carbs and when cranking w/o plugs a mist of fuel sprays out. This blows out...
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