Boat Maintenance and Repair Q&A

The information contained herein is the opinion of ABA member and marine mechanic Tim Harrington of Madison Marine Service, Harwich, Massachusetts. Tim is responding to a question solely based on the information an ABA member provided. Neither ABA, nor Tim Harrington, nor Madison Marine Service assume any responsibility or liability for events that occur due to actions you or others on your behalf take based on the information given in Tim's response.  You are proceeding at your own risk.

Q. I was curious to know why my boat pulls so hard to the right. I don't see a problem with the prop. I just bought the boat and was curious what the problem may be. I have heard of stabilizers and such but just not sure so I'm asking the expert. Thanks for your help.

A. I have received your question regarding your problem with torque pull on your boat. I see that you have 115 hp on a 15' boat. I hope that it is equipped with seat belts!

Above your prop you will see a fin with a single bolt. Mark the position of the trim tab plate and move it in a counter direction to the prop rotational direction in small increments. This trim tab is there to counter the torque that the prop creates in rotation. Following this procedure should stabilize your pull problem

Q. Why is synthetic oil specifically not recommended by Mercruiser for the 4.3 engine?

A. I have not checked with Merc directly, but I would think there might be problems with performance to engine and viscosity breakdown of synthetic oil. Personally I do not use synthetic unless it is recommended or stated as an acceptable alternative to oils. If your engine is one of the new 4.3s, I think they recommend 25/40 or something like that. You need to use what is recommended by the manufacturer to protect any warranty you may have on your engine.

When I have catastrophic failure in a new piece of equipment or if something is out of place with a failure, I send out my oil and other liquids for analysis and try and determine the failure problem, and manufacturers do the same. I would use what is factory recommended to protect yourself and your equipment and to keep any current warranty valid.

Q. I have just had my carb rebuilt and my performance has increased greatly, at take off and speed. I am still having trouble with the engine stalling about 60% of the time when I pull the throttle down to neutral or try to reverse from an idle forward to reverse to dock, here it dies about 90% of the time. The friend that overhauled my Rochester 2bbl carb is a GM master mechanic but has said that he would like some direction from a marine expert. Any ideas to check or solutions?

A. It sounds like things are okay with your carb, and I do not believe a master technician would have a problem with a rebuild kit. From what you're telling me and not knowing the year or serial numbers to your inboard, I don't think your problem is in your carb. You seem to have idle and high rpm with no interference, and it sounds like when you are in low rpm range and shift from forward to reverse at low rpm, you stall. Based upon this, I would look to the interrupter switch, if you have one, and/or your lower shift cable. Take your serial numbers and look at the manual to your engine. Here you'll find rigging and all of the other parts we just mentioned. Troubleshoot by checking the shift cables and interrupter switch to see which is the culprit. Your mechanic friend sounds well qualified to help and the manual will fill in the gaps for him. Hope this is helpful in getting you in the right direction.

Q. I just bought a 1990 Wellcraft 196 Eclipse and I was wondering about the size of the gas tank. The gauge doesn't seem to go much below 3/4, but the first time I filled it I put in 19 gallons. It's a 4.3 liter engine. I'm on Moosehead Lake and it's a long way between gas stations.

A. I think your gauge is ok because it is indicating! I believe that the problem lies in your float being stuck. You may have filled her right to the brim and it rotated to the top of the track on your sending unit.

If you can't bang it loose by running the boat, you will have to remove all your screws to remove it from the tank. You need to scribe a mark that you can match when you put it back in. Try and clean carefully and see if you can get it to go up and down. If it doesn't want to operate, you may need to replace it. Measure it and match the screw holes if you need to replace.

Q. My instrument gauge plastic covers on the bridge are scratched and cloudy but are clear enough when dampened. How do I get them to be clear when dry? I read that polishing with peanut butter would help. Is there a polish that you would recommend?

A. There are several products you can try. Sooner or later, though, you will most likely have to change your instruments. The one thing I would try first is Lemon Pledge. This is used on a lot of plastic materials because, like peanut butter, it leaves not only wax but has lemon oil. Also, there are products like Rain-X and Star Bright that you can try. Hope one of these remedies solves your problem!