New boat, issues found on the water.

[jimmydean_71]

I just picked up my first boat a few weeks ago. It's a 1987 Marlin Aries bowrider with Mercury Black Max 200hp outboard that sounded good when I bought it. I got it all loaded up and ready for the first trip out on Saturday. I got it in the water, running, idles fine, cruised it out of the no wake zone and as soon as I gave it gas, it stalled. Restarted, idles good, open the throttle to rev it, sounds good, put it in gear and it stalls above idle. Does it in both forward and reverse. It sounds a little clunky going into gear, but nothing too awful.

After floating a few hundred yards down river killing the battery trying to get back, a nice couple fishing towed me back in. They said it sounded like my lower unit was bad, but the shop I called said it's usually a dead cylinder or more. If it doesn't have spark or weak power, it will stall under load.

When I got the boat back home, I put the hose on it, rev'ed it up, had it in gear and it seems fine (but again, no load) I adjusted the idle up a little and it sounds great. But I don't want to take it back down to the river and have it leave me again. I will be checking for spark when I get home and will also check the oil in the lower as well.

Would a bad lower unit cause it to stall in gear? Are there any checks I should do to help identify the issue? I am pretty good with cars, but this is my first boat. Thanks for any help.

 

[Guest]

Re: New boat, issues found on the water.

a compression test will rule out your cylinder being bad (if that's not the issue). buy/rent a compression tester asap

 

[jimmydean_71]

Re: New boat, issues found on the water.

a compression test will rule out your cylinder being bad (if that's not the issue). buy/rent a compression tester asap

Compression showed 100psi on all cylinders. Not great numbers, but they were even. After doing some more reading, I will check the spark next. I would think it would not sound as good if one or more cylinders were not firing, but I am not a 2 stroke guy in general.

I hope it's something stupid and NOT expensive, but I know it's only hope. :lol:

 

[GA_Boater]

Re: New boat, issues found on the water.

Welcome aboard, Jimmy. Couple of questions - Do you have fresh fuel and a clean fuel tank? Have you changed fuel filters?

On the lower unit, it's probably a good, no it is a good idea to change the impeller and lower unit oil. I doubt if the lower is the source of the trouble, but it gives you history.

 

[jimmydean_71]

Re: New boat, issues found on the water.

Not sure on the fuel. The boat has twin 15g tanks and one was empty and I put 10g in the other tank before I hit the $99 max on a single fill up. I put plus in it and added 50:1 (might be a little richer than 50:1, but not lean). I was running off the full tank Saturday.

 

[jimmydean_71]

Re: New boat, issues found on the water.

The previous owner had the boat out a few times, one of the pics in the original ad was from last summer, so I know it USED to run just fine. I am a little worried hearing all these stories of people buying boats with issues because I am often a little too trusting sometimes.

I guess since I've never sold anything with a known problem hidden that I assume others do the same. But I know that isn't the case. I do so hope it's a minor maintenance type oversight or issue and not a major problem. I got the nicest boat I could with the budget I had, but my main concern was fining something I could put in the water now and enjoy, but it seems it won't be that easy.

 

[1stgenbird]

Re: New boat, issues found on the water.

I would drain and replace the fuel and replace fuel filters as a 1st step. Likely needs to be done anyway.

 

[jimmydean_71]

Re: New boat, issues found on the water.

Well, I'm not too keen on dumping $100 worth of mixed fuel just yet, but the fuel filters and separator look good. There was almost no fuel in it when I went to the pump, so one tank is full and the other shows 3/4 (about right for 10g into a 15g tank). If I run out of options, I might. Or at least drain it and save it for later if other things don't resolve it.

If I had a 2 stroke dirt bike, I would just use the gas for that, but I only put premium in the Corvette. :lol:

 

[GA_Boater]

Re: New boat, issues found on the water.

Are you spending 9.90 a gallon for gas, $99 for 10 gallons? How much TCW3 did you add for a 50:1 pre-mix? Should have been 28.6 oz.

And sellers are as honest as the day is long.

 

[jimmydean_71]

Re: New boat, issues found on the water.

Are you spending 9.90 a gallon for gas, $99 for 10 gallons? How much TCW3 did you add for a 50:1 pre-mix? Should have been 28.6 oz.

And sellers are as honest as the day is long.

15 (passenger side tank was empty)+10 (drivers side tank is now 3/4 full)= 25 gallons of fuel @ $3.80ish a gallon for plus. It was a total of 25 gallons and I added roughly 2.5oz per gallon, 2.5 quarts I think.

<edit> I tried to fill the boat so I could enjoy it. Guess I should have known better my first time out. :lol:

 

[Guest]

Re: New boat, issues found on the water.

15 (passenger side tank was empty)+10 (drivers side tank is now 3/4 full)= 25 gallons of fuel @ $3.80ish a gallon for plus. It was a total of 25 gallons and I added roughly 2.5oz per gallon, 2.5 quarts I think.

<edit> I tried to fill the boat so I could enjoy it. Guess I should have known better my first time out. :lol:

This might be dumb but does the tank have an air valve and was it completely open when running the outboard. Also check your Lower unit oil by opening the lower screw cap and look for metal in the oil or on the screw. This should help you rule out damage to the Lower unit. Can you post a 2-3 min video of your problem we have super knowledgeable people on here that will diagnose you in a heart beat.

 

[jimmydean_71]

Re: New boat, issues found on the water.

Not sure when I'll get her back in the water, but I'll get a video if I can. I am going to try and work on it this week. I just have to drag it home first.

Its tough because I have to keep it in storage due to HOA rules about boats in the driveway. But I am supposed to move it into a slip on the first. Not sure I want to until I can run it above idle.

 

[1stgenbird]

Re: New boat, issues found on the water.

I still suspect a fuel or fuel flow issue over an internal engine issue. Was the empty tank you filled clean? Possibly it could have had some residue that was stirred up and ended up in the lines clogging filters and impeding fuel flow at higher rpm.

 

[wired247]

Re: New boat, issues found on the water.

I'm thinking more of gummed up carb jets. That and the horrible compression for a 200 but that could just be stuck rings. Decarb!..

 

[1stgenbird]

Re: New boat, issues found on the water.

Yes, a clogged carb is also suspect.
As I don't have familiarity with higher HP outboards (I have and work on <25hp older motors) what would be good compression numbers?

 

[jimmydean_71]

Re: New boat, issues found on the water.

I still suspect a fuel or fuel flow issue over an internal engine issue. Was the empty tank you filled clean? Possibly it could have had some residue that was stirred up and ended up in the lines clogging filters and impeding fuel flow at higher rpm.

I honestly don't know. I didn't inspect the tanks (not something I have ever done on any vehicle). The filters are full of clean fuel, so I don't think there is a flow problem. The filters also stay full as you rev the **** out of it when not in gear without hesitation or miss.

I talked to a guy at a marine repair shop and he gave me a list of things to check as well. If I can't resolve it, they will charge me no more than $100 to go through the whole motor and make a list. I really hope I can get this pig running and in the water for less than a grand. Otherwise, boating aint for me. I'll go back to hotrods and motorcycles. :rofl:

<edit> I was told 110-120 psi was "good" compression on a 200. I know 100 isn't great, but it's at least even across the cylinders.

 

[jimmydean_71]

Re: New boat, issues found on the water.

I will pick up some cans of powertune tonight and give that a go. After seeing the wiring job that was in this boat, I can only guess the engine has never been decarbed.

I've never worked on an outboard, so this should be at least interesting. Hope for the best, thanks for all the tips.

 

[wired247]

Re: New boat, issues found on the water.

100 psi on a 200 merc is pretty bad. 110 is bad but passable. 120 is OK. Its even but on a motor that has sat for a long time the rings could just be stuck in the grooves. Try to get the compression back up with a decarb and pull the bowl plugs out and give the mains a good hosing out with carb cleaner and one of those red straw things. Check the timing.

 

[jimmydean_71]

Re: New boat, issues found on the water.

So the plan for this week is a good decarbing (at least in the driveway), check for spark, check all the plugs and coils and see if this ***** will run.

It's frustrating because everyone who has seen my boat says "Man, that looks fast. I bet it hauls *** on the open water..." :rofl:

 

[jimmydean_71]

Re: New boat, issues found on the water.

Wired247, your boat looks great. I hope my Marlin looks that good eventually (if I don't set it on fire in the middle of the Columbia) :lol: