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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Yes I replaced the wires. The Thunder Bolt IV I have is a sealed box.
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Ok here's the latest update and summary: misfiring / stuttering bad under any load at all. By the end of the season last year we couldn't even use it. It got progressively worse all last year. What I've done so far: Sprayed fuel directly into carb while sputtering to see if it was starving for...
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Ok finally spent a full day on it before winterizing. Ruled out a lifter problem as there is no tapping at all. Ruled out stuck valve as compression test shows good on all cylinders when cold. Used a spray bottle to mist fuel into carb and nothing changed so it’s not a fuel delivery carb...
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Battery terminals are clean and tight. Also the battery is only a few years old and I always get the best one available. 14 volts when idling. Yes electrical bugs can be a buger. I’m an old EE with a lot of troubleshooting experience. I chased that about as far as it goes thinking it was an...
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Yes I adjusted the valve lash when I replaced the heads a few years back. I have seen the technique you’re talking about and yes that does sound messy. But I may not have a choice. Thanks
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Ahh that’s a great idea. Thanks
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Anyone ever had a lifter failure?
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    I tried this and couldn’t find anything. After it’s hot it runs fine. So I think I’ve ruled out ignition. Wire aren’t that old either.
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    It has through hull exhaust that is pretty loud so I can’t really hear the engine that well.
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Update 10/2. I tried misting fuel into the carb during rough idle to see if it’s fuel related. Like maybe water in the fuel or fuel pump problem. No change. It seems to be taking longer for the issue to clear up after starting. Today I attempted 3 times to get on plane before actually being able...
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Update today. Boat has been sitting for a week. Rough as can be when i cranked her up today. Same as before. Extremely rough for several minutes. Even smoked some leaving soot on the water line. Last week after sitting just over night it fired up and ran smooth. This sort of makes me think it’s...
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    I can see where a stuck valve might behave this way. However I’m not sure that would cause the tach to go buzzerk like it does. It will actually read zero for several seconds at a time. I ran it yesterday after pulling all the plugs and reseating all the wires. No change. Took the gray tach wire...
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Ok finally got all the plugs pulled. All dry as a bone and look real good. No water evidence. I’ll try disconnecting the gray tach wire. I’ve never had an ignition coil go bad. Could that act intermittently when cold? I still believe it’s an electrical issue. I’ve checked every inch of wiring...
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    I understand. If a plug is wet it won’t fire at first. That makes sense. What would that be a symptom of? Bad head gasket?
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    5.7L 1984, Rough idle at start up, then ok after a minute or so

    Extremely rough idle upon start up, as if two plug wires are off. Tachometer goes ape s*&t. Then suddenly smooths out after about 1 minute. It's not the choke. It seems ignition related. Could I have a couple plugs failing to fire but then start working? That's exactly how it acts.
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    Starter for 1984 5.7L I/O Mercruiserl

    So I’m experiencing some weak cranking after the boat is hot. Like after swapping skiers. All connections are tight, and my alternator is producing 13.5 volts at idle, and my battery is only a year or two old. I’m thinking it’s the starter or starter solenoid. But I’m having the darndest time...
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    1984 5.7L 260HP timing chain question

    I know I have between 6 and 7 degrees of slack in my timing chain. And I suspect this is the cause of lower than normal engine vacuum and WOT. I'm undecided but considering replacing the chain. Looking at new ones I see they are around $100 or more just for the chain. Looking at the chain for a...
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    couple questions about U joint bellow replacement on Alpha One

    Going strictly by the manual, it doesn't say to apply bellows adhesive to the gimbal flange, only on the bell housing flange. I assume this is just an oversight and the adhesive should also go on the gimbal flange as well. Also, my new bellows came with two clips. Again, the manual only makes...
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    Alpha 1 gen 1 U joint bellows

    So I pulled the outdrive yesterday and did a close inspection of my U joint bellows. I did find a hole about two ribs back from the gimbal bearing at about 11 o’clock on the port side. I could just push my index finger through the hole. And it felt rough like something had rubbed a hole there...
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    Protectant spray for bindings

    I’ve looked off and on for years for something to spray on my ski bindings to protect them from dry rotting. I’m not having much luck. I’ve been using an Armorall type product but it doesn’t seem to help. I’ve actually had people tell me it could be harmful to neoprene. I’ve definitely noticed...
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