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1979 Cobia Monte Carlo Won't start

Hounds

New member
Ok. I am BRAND NEW to working on boats and just got one for almost free. Its been sitting for 3 years tilted upright with drain hole open. And appeared to be winterized ( sort of ). All water drain plugs on the engine were open, plugs looked "mediocre " .
" Shell " appears to be fine or the fiberglass. Anyway, I want to get it running first then work/refinish some of the exterior/interior,etc. My 'plan' is to get it started and running first to see if any major oil leaks, etc. THEN tear everything apart and clean,etc. without total rebuild. Replace all rubber/hoses,etc.,

The Engine is a 4cyl what I believe is a 3.0 L 140 HP engine. All it says ( that I can find ) is OMC on the top and 909466 that's what it sure looks like to me but IDK for sure its hard to read.

ANYWAY, I drained the fuel, put a gallon of clean fuel, new plugs ( but not wires or distributor or cap/rotor ). Oil looks clean, almost too clean.

Turns over but does not fire. I don't think its getting fuel, the pump appears mechanical. Do I need to prime it somehow? When I put small amounts of gas in the carb it starts to fire but won't stay very long. As soon as I take my fingers off the key it stops. Wont stay running.

This boat does not appear to have any plain throttle? Meaning I can't rev it up without being in gear.

Should I go ahead and replace the plug wires and rotor then give it another try? The thing looks brand new inside.

Once again I'm totally new to this. Maybe someone could list the things I should try after this?
Like I said, what my plan was to do is : Replace plugs and wires, rotor, change oil, new fuel and rebuild the fuel pump with new fuel filter. Oh and re-build the carb. THEN go to all the rest of engine and prop,etc.
That's as far as I was gonna go to see if I can get it running.
THANK YOU.
 
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just got one for almost free

Nothing free is ever free, or cheap.
Anyway, I want to get it running first then work/refinish some of the exterior/interior,etc.
I would recommend doing the opposite. That is, inspect the hull for soundness and worthiness. Only if the boat's hull is worth saving would I spend any time on the engine. However, a plastic boat can be brought back from the dead with enough love and money thrown at it.

As to the engine, usually the reason a bot ends up sitting is that there is something wrong with it and the owner is too cheap or lazy to get it repaired. Often it is a small thing
 
Yeah, already did the body and hull inspection fairly well before I took the boat on. All visual . no cracks and the areas that I could see under the floor look super. One spot I found in the center of the boat, looks like it was a live-well or access hatch. Small area maybe 18" X 24". Was covered with plain old ply wood and rotten. I tore the entire carpet off too to check the floor. What appears to be OEM fiberglass laminated plywood? But not 100% certain that's it. BUt it all looks and feels solid all the way to the side of boat.
Some fiberglass rips in the thin area covering half the motor and around the fuel tank on top where obvious tinkering or whatever with motor and tank were going on over the past 36 years.
Already 'plan' on spending thousands in the motor. I'm planning ahead, not planning to fail.
Assuming the boat ran last year, what steps should I take with the motor? Should I simply yank it and work on it in garage? Or is that a bastard to put in and take out? It is a smaller engine ( compared to my diesels ).
I'm even contemplating taking just the engine to a local marina to have them re-build. What sort of price is that for a 3.0L depending on where ya live I"m assuming. But if I were to do that is it better to drop off and leave the entire boat so they could inspect or also check out the rear end and everything?

I'm fairly good with engines, ( diesels more so ) but this has got me slightly baffled. For the immediate time being I am thinking go get the fuel pump re-built, put a new rotor and cap with wires, re-do the carb THEN check to see what happens then.

I'm not overly worried about the hull and shell, however is there some specific thing I should be doing as a test of sorts? Like I said, no obvious cracks or signs of repair, all looks original faded gel coat. minor scratches. There are two large storage areas under the bow seats that come out. I looked under them and that area looks real good. Whatever black thick coating they put on the fiberglass looks good and clean.
Is there some sort of stress test that marina's do?

https://youtu.be/5tGxkFX6KJU

This video is the engine I have. At the 2:00 min. mark I noticed they installed what appears to be an electronic fuel pump. Are these old mechanical ones known to not provide enough fuel?

Thanks.
 
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First thing to check is whether PO left it out in the winter full of water and cracked the block. That would certainly be a downer.
Honestly the only compelling reason not to buy a remanufactured engine and turn in the old one as a core is if it is such a valuable or oddball thing that nobody has a replacement ready to go. Our hosts sell remanned engines at very very competitive prices, and for way less than what it will cost you to do it on your own.
 
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