Can't keep engine running...

[mrallen007]

I just bought a boat with a 91 Merc 50 ELPTO. The day I bought it, it ran like a champ (of course). Now it runs more like a chimp. It takes a fair bit of effort to get her to start. It's not uncommon to kill the battery trying. Now, I can't seem to keep it running.

Once I get it started, it will run in short spurts and eventually die. When it is running, if I put the gas to it, it often bogs down and tries to die. I have to ease into it to get the rpm's up. I can't test it too much in my driveway even though I'm running water to it so I don't know what it will do at high rpm's. It runs kinda rough, backfires now and then, and lopes and shakes a lot. Is this just a timing issue? Is it a problem with the carbs? Is it something I can easily adjust? Or do I just need to find a good shop and say goodbye to the lake for a little while? Any advice would be appreciated.

 

[Mi duckdown]

Re: Can't keep engine running...

High rpms is bad in driveway, Hose or barrel. No resistance.
How mechanical are you?
An OEM (ONLY) MERC manual is about 100 bucks new. Boat shop is 80 bucks an hour.

 

[mrallen007]

Re: Can't keep engine running...

I avoid high rpm's out of the water. I've pushed it barely beyond idle in the driveway in working with it, but that's all. I admit, I don't know much about outboards, but I'm pretty mechanical generally speaking. I bought a tech manual, the SELOC manual, and I've tried some of the general maintenance tips. I'm just not sure where to go next.

I changed the plugs and the fuel filter. I went through the steps to ensure the carbs were all working in unison. I've not done much beyond that.

 

[Mi duckdown]

Re: Can't keep engine running...

Do you have fresh gas/oil mixture?

 

[mrallen007]

Re: Can't keep engine running...

It's an oil injected two stroke. There's plenty of 2 stroke oil in the resovoir and the gas is fresh.