'93 Malibu Echelon: Transom leak and hesitation from idle

[sticknrudder]

‘93 Malibu Echelon 350 Mercruiser magnum competition ski carbureted. Got it out on the water for the first time since purchase. Two issues: 

1. Leak above floor level. After 1 hour on the water of testing water coming up through carpet from back of boat. Pulled carpet up on that side and its drenched underneath. Some have mentioned rub rail leak. Seems like a lot of water for something so high above water level…

2. Engine stumbles accelerating from idle. Have to milk it to keep it running then it jerks to life. After that is accelerates normally no problems. Idles 650 rpm. Reman carb last year, fuel filter last year, fresh ethanol free gas. Runs and idles great otherwise, just coming off stop. Seems to be worse longer it has idled prior to acceleration.

[justgary]

650 is the correct idle.

Your leak might be caused by the platform bracket bolts also.

Do a full tune up including plugs, wires, cap, and rotor.

[justgary]

Oh, and the hesitation could also be a misadjustment of the acceleration pump in your carb.  I would still do the full tune up first.

[sticknrudder]

Ok I could do a tune up. I am thinking maybe your guess about the accelerator pump might the most accurate. But...also odd considering the carb was just remanufactured...

[Steve B.]

Plop a timing light on that machine too and see where you are at.

Steve B.

[sticknrudder]

I finally was able to upload a video I got of the boat the other day when testing it. Does this help narrowing the diagnosis any?

 

 

[justgary]

45 minutes ago, sticknrudder said:

I finally was able to upload a video I got of the boat the other day when testing it. Does this help narrowing the diagnosis any?

 

 

Is that after the tune up?

[sticknrudder]

No, haven’t had a chance to do that yet. Just a video I found from when I tested it.

[Woodski]

+1 on accel pump arm position, float level could also be an issue.  Is the reman a true marine carb with the correct calibration?  Cars & boats are very different.

[sticknrudder]

40 minutes ago, Woodski said:

+1 on accel pump arm position, float level could also be an issue.  Is the reman a true marine carb with the correct calibration?  Cars & boats are very different.

I like the idea of it being accel pump arm position. Sounds like an easy fix. How do I check that and what is correct vs incorrect? The extent of my knowledge is cleaning a set of jet ski carbs. I bought the boat this winter, previous owner took it to a marina to have the work done and they're the ones that put the reman carb on there. I have the invoice for it. But not sure beyond that. I assume it would be marine being it was a marine mechanic who did the work. Boat starts very easily.

[sticknrudder]

This was the receipt given to me by the previous owner. All work was completed last June.

[Woodski]

It may end up a trial and error effort, it’s an easy change (but get a bag of the little circlips first) to do and go run.  Assuming a Weber carb from the era of boat.