Used Boat Test Drive -- Issues

[jwharan]

I test drove a boat yesterday that I am buying. I have a few issues that I could use some help with.<br /><br />First, The boat starts and idles properly, but tends to stall when I try to go into gear. Even if i throw the gear down hard, it wants to stall about 50% of the time. I want to say the engine just sounds like it is running way to rich. Once I am in gear, and moving around, the boat runs great.<br /><br />My next question is probably my misjudgement and not the boat. First, i am not sure how to use Trim, Should it be up down or in the middle? when do i need to adjust it? 2nd, If I accelerate beyond a certain point, or too quickly, the boat seems to "spin in place" the RPMs shoot up, but the boat doesn't go anywhere. I have to throttle down to almost neutral, in order to regain momentum. Also, sometimes the boat will shake when I accelerate to fast, perhaps this has to do with my trim setting, not sure. Can anyone offer some advice to my issues here? Thanks!

 

[vipzach]

Re: Used Boat Test Drive -- Issues

What year, motor and drive is it? There is a switch that is supposed to mometarily stall the motor to allow it to go into gear easily, maybe it is out of adjustment. <br />The trim should be down all the way when you first tale off and adjusted up(some) once on plane.<br />"spin in place", that sounds like the prop might be spun. Even if the trim was too high, the bow should come up and have a hard time planing.

 

[lenny2113]

Re: Used Boat Test Drive -- Issues

First, The boat starts and idles properly, but tends to stall when I try to go into gear. Even if i throw the gear down hard, it wants to stall about 50% of the time.

This sounds like lower shift cable is causing a problem. To replace the cable, you would need to get the boat out of the water.<br /><br />Start with trim all the way down. Once boat is on plane, trim it up just a little to get the bow out of water for comfortable ride.<br /><br />Your questions may be answered in more details once you provide information about your boat model, motor type and prop size.<br /><br />Good luck!<br />P.S. Take as much time as you need testing and examining the potential new toy before making it yours. There will be tons of other boats for sale even if you miss this one. DO NOT RUSH. DO NOT BY ON HIPE. Buy on careful research.

 

[jwharan]

Re: Used Boat Test Drive -- Issues

This boat is a sea ray 185, 4.3L Merc

 

[jwharan]

Re: Used Boat Test Drive -- Issues

What causes the RPM to jump, and the boat to essentially slow to a standstill, (similar to knocking a car into neutral while driving?)

 

[lenny2113]

Re: Used Boat Test Drive -- Issues

vipzach, <br />I did not copy your reply, I was typing mine. <br />I would second (possible spun prop hub).<br /><br />Stalling while going in gear:<br />Disconnect shift interrupt switch by taking off one of the two wires connected to the shift plate.<br />If the engine shifts without stall while the wire is disconnected, change lower shift cable. <br />Also change brass bushing and seal that are on the bell housing under the shift arm.

 

[lenny2113]

Re: Used Boat Test Drive -- Issues

What causes the RPM to jump, and the boat to essentially slow to a standstill, (similar to knocking a car into neutral while driving?)

Start with checking the prop (spun hub)

 

[vipzach]

Re: Used Boat Test Drive -- Issues

If the prop is "spun" like I mentioned above the rpm's can go up and the boat not move. What that that means is that the prop is slipping on the hub. You could also have other drive problems, but it sounds like a spun prop. Any sounds you hear when it happens. Lenny's suggestion about the lower shift cable would a likely problem with the stalling also.

 

[jwharan]

Re: Used Boat Test Drive -- Issues

I will check the prop cable Thanks. What causes a spun prop, and how do I remedy this problem?

 

[vipzach]

Re: Used Boat Test Drive -- Issues

The prop could be worn out, impact is what can cause them to be spun also. There is a rubber bushing inside of the prop that will break if the prop hit something to help prevent damage to the lower unit. You can buy a new prop to fix it. You can mark the prop with nail polish to confirm that is the problem.

 

[jwharan]

Re: Used Boat Test Drive -- Issues

Anyone else have any info on a spun prop? What is the procedure to test? and perhaps replace the prop? I have never done this? I am assuming a spun prop means the drive shaft is spinning around inside the prop, (essentially acting like stripped screw in a hole?)

 

[lenny2113]

Re: Used Boat Test Drive -- Issues

A little bit wrong... <br />It means the hub is spinning inside the prop.<br />Take the prop off and show to marine mechanic. It may need to be "re-hubed". This should be done by special prop shop

 

[novicetech]

Re: Used Boat Test Drive -- Issues

jwhararn, some times if you trim up too high the prop gets too high in the water it will be running on top of the water, this could cause the condition you are talking about. Go ahead and ask for another test and follow the instructions that lenny and vipzach have already given you. make a mark on the prop casing into the prop hub. If the mark does not line up when you get done, the hub is spun. About the trim start with the trim all the way down, when on plane trim up until boat starts to porpoise and then back down until porpoising stops.

 

[Wotknot]

Re: Used Boat Test Drive -- Issues

And to add my 2 cents of opinion..... If this is the first time you've ever bought a boat -new or used- take someone along with you that knows boats, whether a friend or a surveyor (money well spent) You'll be less likely to get burned.

 

[Uncle Dave]

Re: Used Boat Test Drive -- Issues

Where was the "owner" while you were test driving?

 

[DHPMARINE]

Re: Used Boat Test Drive -- Issues

Sorry ,I didn't read past your first post,so maybe I missed things here.<br /><br />What stopped me was 'stalls almost 50% of the time'<br /><br />Shouldn't that stop you as well ?<br /><br />DHP

 

[Don S]

Re: Used Boat Test Drive -- Issues

You're spending big bucks on a used boat. Owners selling the boat aren't going to tell you the things that are bad or going bad.<br />Best thing to do is get a survey, and as Wotknow said, it money well spent.<br />Also, if the boat passes the survey, have a good Mercruiser dealer do a mechanical check and test run on the boat. I just did one last year that the selling owner paid to get a new coupler, rear engine mounts, manifolds, risers, raw water pump, a lot of small items done so he could sell his boat. The bill was over 5K.

 

[jwharan]

Re: Used Boat Test Drive -- Issues

Let me be a bit clearer about the stalling, it stalls about 50% of the time, when I attempt to shift into gear, which means i could be doing something wrong, as well. While in gear, it runs great.

 

[lowshovel1]

Re: Used Boat Test Drive -- Issues

I'm curios like Uncle Dave----Where was the owner???????

 

[jwharan]

Re: Used Boat Test Drive -- Issues

I signed a promissory note, basically stating that I have one week to test out the boat, get a surveyor. and then either buy the boat, or return it. I am a great negotiator. Essentially, I have a free boat for a week, on the owner's insurance, and registration.