Unknown O/B problem, please help

[Franco749]

Hello All,

I have an 82 Boston Whaler which has an 82 Mercury V-150 outboard. I was boating yesterday, everything was running wonderfully. Boated all day, took a break and then went back out. I was running it for about 5 minutes only, and I put it to full throttle for maybe thirty seconds before the general tone of the engine change slightly, and then about 10 seconds after that, the engine started running really crappy and quit. Then it wouldn't start again and I had to get a tow in. It sounded like it wanted to start, but you'd only get 3 or 4 cylinder fires out of it.

Here are some things to note about this motor:
I did notice that when idling it tended to not sound like it was running completely evenly, like maybe occasionally misfiring or something,
AND
It's always been a hard start, maybe 15 minutes of screwing with it sometimes, but once warmed up you could shut it down and start it up fine.
ALSO
Although ALWAYS being very cautious to give correct fuel mix, it always seemed to smoke more than average two stroke motor, like it was running super rich.


I don't know much about repairing outboards. I'm wondering what the problem could be. Would it be possible that the spark plugs are just bad? I won't be able to work on it for a few days yet and I kinda want to have an idea of what it could be.

Thanks,
Steve

 

[Laddies]

Re: Unknown O/B problem, please help

Sounds like Ign. trouble here's a test from CDI

 

[Franco749]

Re: Unknown O/B problem, please help

Thanks for the post. I went to start following this page you posted and started with removing the spark plugs. Then one I removed one of them I saw a chunk of metal. I blew a rod right through the piston. $5k to rebuild according to the marina.

QUESTION: I have helped people rebuild car motors/cylinder heads,etc., but never done a full rebuild start to finish. I have the repair manual specific to my motor, and found a rebuild kit with new rods, pistons, bearings, gaskets, etc., supposedly EVERYTHING I need to rebuild. How much difficulty am I looking at? The kit is $1200. Also how much time am I looking at (and remember that I'm a beginner).

Thanks,
Steve

 

[Laddies]

Re: Unknown O/B problem, please help

Most rebuild kits are a rip, if you want to tear it down do it if you don't have a manual available to look at go to a online part book to see how it comes apart then tear it down to see what it will take to fix it. It may have a damage block where it's not worth the cost of repair. You may be able to find a used powerhead or at least some parts from a doner engine. Remember alot of the advise on these forums comes from people with a lot less experiance than you have so if the advice don't sound right to you it probable is not right.

 

[Silvertip]

Re: Unknown O/B problem, please help

By all means DO NOT buy anything until you are absolutely certain the block has not been damaged. Chances are the metal that bounced around inside that cylinder has scored it. YOu cannot put a new piston and rings in that cylinder and expect it to last more than 10 minutes. Even if there is no cylinder wall damage, all bores need to checked for diameter, out of round, and taper. If out of spec it needs to be bored and oversize pistons would be needed. If you do intend to rebuild the engine, you are advised to rebuild the carburetors as well since one of them probably contributed to the problem because it was clogged and the engine was running lean. Running lean on fuel also means it was running without enough oil for lubrication. Failure to do this will certainly cause the same problem again.

 

[Laddies]

Re: Unknown O/B problem, please help

Its a chrome bore, if damaged and you can't find a doner, US Chrome are the people to repair it.