Bunk placement

TinBoats.net

Help Support TinBoats.net:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Boomer85

Member
Joined
Oct 20, 2021
Messages
7
Reaction score
0
Location
St. Louis MO
Hi everyone.

First post follows buying my first boat and problems that come along with it :roll: :

Purchased a 1997 Lowe 170. Price was more that right, no complaints. 24 volt trolling motor, 50 hp Merc(that runs but needs some work) all new batteries, etc. I didn't think I got hurt too bad.

Problem is it takes on quite a bit of water. The first couple of times it took a couple of hours for me to notice it just starting to come up from the drain in the middle of the floor. Bilge pumped it out, no problem and only had to use it one more time. Next several times I took it out, I would have to turn the pump on within 10 minutes and maybe every 20 min or half hour afterwards.

Long story short, there are two crack in the transom(?) right above where the boat rests on the bunks. Bunks stop short of the end of the boat and have indented into the bottom of the hull.

I guess my questions are; is this common and is there any lasting structural damage after I have it welded-repaired and should the bunks extend past the end of the boat? I have new bunks to put on and don't want to add to the damage or cause the same thing to happen after the repair.

Thanks for the help.
 
My thinking is that either the bunks or at least the rear keel-roller should support the underside of the transom. At least that's how I've set up the boats I've owned...including the newest one.
 
If the bunks are for sure the problem, I would personally extend them all the way through to the rear of the boat. Also, maybe this is the type of boat and motor combination that needs a transom saver if you don't already have one, but it's hard to tell with out any pictures what your set up looks like. It's true what they say: Pictures are worth a thousand words.
 
Good deal. I hate to hear that you are dealing with something like this on your first boat. I also can't believe that the guy that sold it to you never brought up that the boat took on water. I mean, I can believe it, but whenever I have sold boats, I tell the buyer every single detail and problem up front because I believe in being honest and I don't want anyone to ever call me back and accuse me of hiding something or lying to them.
 
Striper57 said:
Good deal. I hate to hear that you are dealing with something like this on your first boat. I also can't believe that the guy that sold it to you never brought up that the boat took on water. I mean, I can believe it, but whenever I have sold boats, I tell the buyer every single detail and problem up front because I believe in being honest and I don't want anyone to ever call me back and accuse me of hiding something or lying to them.

We need a 'Like' button on this board. :D
 
Striper57 said:
Good deal. I hate to hear that you are dealing with something like this on your first boat. I also can't believe that the guy that sold it to you never brought up that the boat took on water. I mean, I can believe it, but whenever I have sold boats, I tell the buyer every single detail and problem up front because I believe in being honest and I don't want anyone to ever call me back and accuse me of hiding something or lying to them.

Full disclosure: He did tell me it leaked - a little. Again, the price was right. Unless, of course, I have to spend 5k to get it fixed. I don't think it will come to that but I am learning about this as I go.
 
MN Fisher said:
My thinking is that either the bunks or at least the rear keel-roller should support the underside of the transom. At least that's how I've set up the boats I've owned...including the newest one.

No roller just two 8 ft bunks. Maybe this is something I should add to help distribute the weight?
 
Boomer85 said:
MN Fisher said:
My thinking is that either the bunks or at least the rear keel-roller should support the underside of the transom. At least that's how I've set up the boats I've owned...including the newest one.

No roller just two 8 ft bunks. Maybe this is something I should add to help distribute the weight?

I would - the keel is the base for the whole boat and the single strongest part of the hull. Having keel support, at least IMO, is necessary.
 
Boomer85 said:
MN Fisher said:
My thinking is that either the bunks or at least the rear keel-roller should support the underside of the transom. At least that's how I've set up the boats I've owned...including the newest one.

No roller just two 8 ft bunks. Maybe this is something I should add to help distribute the weight?


The transom should be fully supported by the bunks. The bunks should extend past the transom.

The following is my opinion:

There is no need to have the keel sitting on rollers except for the roller under the bow. Think in terms of a three leg stool - it is stable even if one of the legs is slightly shorter. The boat is supported by the two bunks and the bow roller. It is stable. You don't want the boat bouncing up and down on a center roller. That doesn't mean you shouldn't have rollers along the keel. They are great for loading/centering the boat, but not for transporting it.
 
I was looking at some online pics of Lowe 170s and they use the same trailer design that most all Lowe boats still use. The trailers just use two bunks and a bow roller to support the boat and the connecting pillars on the trailer frame are bent down into a U shape in the middle, so I don't think he could install a center keel roller if he wanted to. How much weight is in the rear of the boat while trailering it? Also, avoid bouncing the trailer as much as possible while driving. Also, I assume you are using rear transom tie downs, so make sure they are tight and secure when trailering.
 
Striper57 said:
I was looking at some online pics of Lowe 170s and they use the same trailer design that most all Lowe boats still use. The trailers just use two bunks and a bow roller to support the boat and the connecting pillars on the trailer frame are bent down into a U shape in the middle, so I don't think he could install a center keel roller if he wanted to. How much weight is in the rear of the boat while trailering it? Also, avoid bouncing the trailer as much as possible while driving. Also, I assume you are using rear transom tie downs, so make sure they are tight and secure when trailering.

I looked at quite a few pics myself but it's hard getting a good view of the rear of the boat as far as where the bunks end. It would make sense to me that they should be at least even with that back of the boat. Since that is where my problem is I could simply be assuming too much. And yes, I do use the transom tie downs.

I think when my son and I go fishing this weekend, I will let him fish for a while and I will put the new bunks on and move them back a couple of inches to where they are even with the boat. I bought some marine urethane to temporarily patch the cracks and at least slow down the leak. I don't see any harm in trying that for the next couple of months. I'll get it fixed this winter while I'm not using it.
 
Boomer85 said:
Striper57 said:
I was looking at some online pics of Lowe 170s and they use the same trailer design that most all Lowe boats still use. The trailers just use two bunks and a bow roller to support the boat and the connecting pillars on the trailer frame are bent down into a U shape in the middle, so I don't think he could install a center keel roller if he wanted to. How much weight is in the rear of the boat while trailering it? Also, avoid bouncing the trailer as much as possible while driving. Also, I assume you are using rear transom tie downs, so make sure they are tight and secure when trailering.

I looked at quite a few pics myself but it's hard getting a good view of the rear of the boat as far as where the bunks end. It would make sense to me that they should be at least even with that back of the boat. Since that is where my problem is I could simply be assuming too much. And yes, I do use the transom tie downs.

I think when my son and I go fishing this weekend, I will let him fish for a while and I will put the new bunks on and move them back a couple of inches to where they are even with the boat. I bought some marine urethane to temporarily patch the cracks and at least slow down the leak. I don't see any harm in trying that for the next couple of months. I'll get it fixed this winter while I'm not using it.

I think that you have a good plan to move the bunks back. However, instead of moving them to be even with the transom, consider extending them past the transom by 1/2" to 1". Sorry for being repetitive.
 
How is the tongue weight and how close to the transom do the bunks end? You might be able to pull the boat farther forward on the trailer and not need to move the bunks. You would need to move the front bow roller forward as well as the neck. My bunks extend past the transom about 1/2 - 1". My trailer originally had rollers and the boat sat too high so I swapped them out for bunks. Here's mine the day I put the bunks on and ended up tweaking it a little more after this picture.
 

Attachments

  • trailer7.jpg
    trailer7.jpg
    453.1 KB · Views: 632
How is the tongue weight and how close to the transom do the bunks end? You might be able to pull the boat farther forward on the trailer and not need to move the bunks. You would need to move the front bow roller forward as well as the neck.[/quote

Being new at this boat stuff, I hadn't thought about the boat being properly balanced on the trailer. The boat does seem to lean back or up just an inch or so when I release the strap from the eye in the bow to put it in the water which could be putting undue stress on the bottom of the boat. I guess? Moving the whole boat forward kinda makes sense.

I will try to get some pictures uploaded ASAP.

Thanks for the replies.
 
It is important that the tongue weight be 10% to 15% of the boat/trailer weight. Too little tongue weight can cause catastrophic fish tailing. Too much can potentially overload the tow vehicles rear suspension causing control issues.

Sounds like the boat is rocking forward when you tighten the winch strap. You don't want to lever the boat with the winch strap. When the boat is fully loaded on the trailer the winch post roller/pad should be right up against the boat. Take a look at JL8JEFF's photo above.

There are different ways to adjust the bunks so they extend past your transom by 1/2" to 1". You can move the boat forward, move the bunks back, or put longer bunks. If the tongue weight is OK the way the boat currently sits, then IMO the easier way is what you described. Launch the boat. Move the 2x bunk boards where they should be (no need to remove the bunk support brackets).

Sounds like a few tweaks are needed to have the boat fully supported on the trailer.
 
$5K sure sounds high for patching the cracks. Are they completely replacing the transom?

For that kind of money, you could buy a welder & do it yourself.

Whatever they do, they should reinforce it so it is stronger than original.

All the above advice on transom saver & trailer support is spot on.
 
I took everyone's advice and moved the bunks back to where there is about half an inch sticking out from the back of the boat. Then researched how to lift the boat off the trailer to better see and fix the cracks in the hull.
Long story short, I used flex seal tape as a temporary fix. I've had the boat on the water twice for a total of 8 hours or so and haven't used the bilge once! If that gets me through the fall I'm happy.
Anyway thanks for the help and I realize how much I have to learn about boat ownership and maintenance.
 
Phil Swift would be proud!!! Glad that you found something to work for you to get through the fall fishing season. Be sure to get it worked on this winter and don't procrastinate (which we are all guilty of) because spring comes faster than you think!
 

Latest posts

Top