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    Engine swap, 305 -->350 on a cobra

    I have a 350 block available, so I am researching the feasibility of swapping it out for my current (crappy) 305. This is in a 1986 SeaRay with a Cobra on it. I need to check that the rear seal and drive system will mate up, and that the outdrive can handle the extra power. I should be able to...
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    Voltage drop at ignition switch

    Tried this in electrical forum but no joy: When I turn my ignition switch on, I get a .9 (~12.7v to 11.8v)volt drop without the engine running. This is measured from (-) straight to the battery and (+) at the terminal on starter switch. No load in the circuit other than the instrument cluster...
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    Voltage drop on ignition circuit

    When I turn my ignition switch on, I get a .9 (~12.7v to 11.8v)volt drop without the engine running. This is measured from (-) straight to the battery and (+) at the terminal on starter switch. No load in the circuit other than the instrument cluster (standard gauges, nothing electronic) and...
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    Help! OMC 5.0 no acceleration

    Looking for a little help. Currently on a boating vacation, and the boat wont go... 86 OMC 5.0. Just resurfaced heads, fresh cam, new points, plugs, rotor, oil. Timing at about 6` BTDC. Dwell at 33`, and doesn't drift. Advance weights advance and return normally. Boat starts fine, idles at 500...
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    Timing retarding instead of advancing.

    OMC 5.0 Chevy 1986. Can't find an answer with search... I adjusted the timing to 13` BeforeTDC at 500 RPMs. When I idle up to about 2000RPM, the timing is retarding to about 20` BTDC. Could I have put my advance weights on upside down or something, or is 2k still to low for the advance to...
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    No Compression after rebuild

    I just finished rebuilding my OMC 5.0 Chevy. Heads were machined, new exhaust valves, and a new cam, as well as new exhaust manifolds. FELPRO Marine gaskets everywhere that needed them. I used OMC gasket sealer on all paper gaskets, but none on the head gasket as that is what the OMC book said...
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    Parts comparisons

    I've been reassembling my OMC Chevy 5.0, and am having trouble getting some parts. My book says that Oil filter should be purolator PER 40 or AC-PF 35. My parts stores only carry fram, and stp. Does anyone know the equivalent model #? Same deal with spark plugs. Book specs RV8C's, but parts...
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    Completing rebuild advice

    Hey everyone! I am just completing rebuilding my OMC 5.0. I got the heads machined, new exhaust valves, and a new cam/lifters. Is there anything that I should watch out for that might not be covered in the OEM manual before the first start up? Also, does anyone recommend any particular oil...
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    pulling the heads

    Hey all! 86 OMC 5.0 Chevy I'm pulling my heads to change the gasket, and wanted to ask if there is anything to look out for. I have my OMC manual, and will be following that. Once they are off, I will be taking them to the machine shop to get refurbed. I was quoted $425 for full machining...
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    Pictures from my engine. advice please!

    I took some parts off the engine, and need some advice from you guys please. I'll put links instead of inline pics because they are huge! Its an 85 OMC 5.0. Chevy Looking at the valve covers, there is rust on the inside. Is this normal? The valve springs and all of the parts on the engine are...
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    upgrade ignition on omc 5.0

    I suspect that I will need to replace the advance weights on my 86 omc. Should I take this opportunity to upgrade to an electronic ignition? If so, what are my options? Thanks!
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    OMC carb issues?

    Hey list! Took my 5.0 OMC out the other day, and have some questions. Boat starts fine cold. Idles nicely, etc. The boat is very slow to accelerate and get on plane, and generally runs like a dog until it gets up to speed. Once I'm at top speed (which is in spec at 4300 RPM WOT), it runs...
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    Compression and timing

    Just got back from a little engine work. V8 Chevy OMC. 1986. Getting ~120 psi on all cylinders except #3 at 50 psi and #4 at 90 psi. Squirted some oil into both, with no change in compression. #3 spark plug looked different than all the others: damp (I assume oil, didn't evap like gas) and the...
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    Troubles a-plenty with 5.0 V8 OMC

    I'm having troubles with my 19' 1985ish sea ray bow rider. It has a cobra I/O with the 5.0 V8. Hrs gauge says around 570 IIRC. More info available if you need... It has quite a few small problems, so help me with what you can please. I'm pretty mechanically inclined, but I haven't spent much...
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