Boat Sliding up Bow Stop Roller on Braking

[Gearhead62]

I slid my winch stand forward today 1.5" on the tongue, to get more tongue weight. Additionally, I moved my winch base up 2.0" on the winch stand, in order to get my winch strap level w/ boat eye (possible mistake?). You'll notice I also have a red shackle strap that pulls boat eye down towards trailer frame for added stability.

Got it all tightened and torqued, but noticed boat itself never really pulled forward on rollers. The tension on the transom straps were almost unchanged, but I was very tight on the winch....strange

Went for a spin, drove fine, did a hard brake check and the boat slid forward and up a few inches, up the bow roller stop, and made a thud...Turns out boat slid forward 3-4 inches on rollers - and my very aft rollers (4), that support just underneath the stern, had slightly broken the plane on the transom and were starting to climb up transom on a 45 degree angle - not good. Rolled in reverse, hit brakes and snapped boat back up on all rollers, bow came back down to normal, retightened, parked.........I'm puzzled on the physics here - why is this happenening? Never did before. Any ideas beyond another red strap to pull eye down tighter, so boat won't crawl?

Thanks!
Gearhead

 

[Gearhead62]

Re: Boat Sliding up Bow Stop Roller on Braking

A few additional shots

 

[foodfisher]

Re: Boat Sliding up Bow Stop Roller on Braking

Bow eye under the lowest roller would prevent the ride up.

 

[Expidia]

Re: Boat Sliding up Bow Stop Roller on Braking

Bow eye under the lowest roller would prevent the ride up.

Ya, I was thinking the same thing. I'd even swap out that double roller for a single one. That double is always going to give you a wobbley effect in my opinion. The bow only need rest aqainst one decent sized roller. Try one out from your local Walmart. If nothing changes just swap it back and return the new one.

 

[Gearhead62]

Re: Boat Sliding up Bow Stop Roller on Braking

If bow eye goes under lowest roller, I'll need a taller winch stand...Winch strap is currently fed between the 2 rollers on bow stop

I read that winch strap should always be level, so I adjusted. Maybe that's how the winch lost the down ward pull force when I slid it up "to level"

 

[04fxdwgi]

Re: Boat Sliding up Bow Stop Roller on Braking



Actually, the bow eye between the 2 rollers is the proper way for it to sit, if the winch strap pulls it straight, or slightly downward. Here is a pic of mine and I have zero problem like you describe, bit I don't have rollers (which move much easire than the bunks I use). Looks like you could lower your winch a tad, so it pulls down just a little, as it looks like it is pulling upward a bit. I added a safety chain running from the bow eye to just aft on the trailer to keep rig from sliding forward in addition to the chain running forward, to prevent rearward sliding. I don't keep the chains super snug, using them basically as safeties, but use ratchet straps alongside the chains to keep things tight, but flex a bit to prevent excessive stress on the bow eye when going over bumpy roads.

 

[JB]

Re: Boat Sliding up Bow Stop Roller on Braking

Disconnect the safety chain from the winch stand and connect it, with a turnbuckle, directly to the trailer frame. That will correctly secure your boat in any emergency maneuver.

 

[Home Cookin']

Re: Boat Sliding up Bow Stop Roller on Braking

this is also why you do not have your transom sitting on the roller. the last roller should be at least 4" from the stern. Most boats are set with more than that and no it will not hurt your boat.*

I think I gave this advice to someone concerned that his boat was 14" hanging past the rollers--I said leave it or at most cut the distance in half.

*tinnies may need support further back than glass boats do due to soft bottoms

 

[Gearhead62]

Re: Boat Sliding up Bow Stop Roller on Braking

Thanks for posts...Will try some more adjustments today. I like the turnbuckle idea for tight safety

 

[Thalasso]

Re: Boat Sliding up Bow Stop Roller on Braking

Thanks for posts...Will try some more adjustments today. I like the turnbuckle idea for tight safety

Your straps on the transom seem to be going in a forward angle Secure them to the boat so they are at
least straight down from the transom.

 

[Expidia]

Re: Boat Sliding up Bow Stop Roller on Braking

If you google winch strap position you can see some some trailer manufactuers recommend that the eye comes up snug below the roller. That's why I'm not a fan of those double rollers. If you bring it up snug under the lower roller why would you need the top roller?
I also use an added safety strap to further keep the bow from bouncing around plus if one doesn't have one of those chrome bow protectors the extra strap helps from execess movement which wears down into a boat's finish.

 

[UncleWillie]

Re: Boat Sliding up Bow Stop Roller on Braking

The witness marks on the trailer indicate the winch was recently moved forward.
Move it BACKWARDS so the bow eye is just under the front roller.
When you brake, the bow eye hitting the front roller will stop the boat from moving forward.

Edit: Re-read the thread. :facepalm:
Moving it forward was OK for the weight shift you wanted.
Moving it UP was bad for the braking issue.
Moving it back DOWN should return you to a well behaved boat!

 

[Gearhead62]

Re: Boat Sliding up Bow Stop Roller on Braking

I moved winch plate back down the stand, got better control back on preventing boat trying to climb up rollers, when braking. I left the stand adjustment forward on the tongue for now.

So it appears the only way to accomplish my primary objective - "more tongue weight",.... is to slide the axles back a few inches, but seems like not much room left. Any other ideas on hitting 10% tongue weight?

FYI - I can lift the tongue rather easily and when I stand on the swim platform, the trailer starts to bounce up (I weigh 205 lbs), hence my concerns. I like tandems but this one has me puzzled

Thanks again

 

[Thalasso]

Re: Boat Sliding up Bow Stop Roller on Braking

I moved winch plate back down the stand, got better control back on preventing boat trying to climb up rollers, when braking. I left the stand adjustment forward on the tongue for now.

So it appears the only way to accomplish my primary objective - "more tongue weight",.... is to slide the axles back a few inches, but seems like not much room left. Any other ideas on hitting 10% tongue weight?

FYI - I can lift the tongue rather easily and when I stand on the swim platform, the trailer starts to bounce up (I weigh 205 lbs), hence my concerns. I like tandems but this one has me puzzled

Thanks again

You move the winch stand forward more and you will obtain the tongue weight you want. Then move the boat to the stand. I see from your pic that there is a few inches left. You don't need much to get more weight there.You will need to adjust the rollers on the stern forward also for they might be to close to the transom. The rollers on the hull closest to the bow will need to be lowered also. They will become to high because the bottom of hull be be at the lowest part.If that makes any sense.

 

[04fxdwgi]

Re: Boat Sliding up Bow Stop Roller on Braking

Disconnect the safety chain from the winch stand and connect it, with a turnbuckle, directly to the trailer frame. That will correctly secure your boat in any emergency maneuver.

The pic doesn't show it, but the chain passes below the winch and down to the trailer frame to the hardpoint connection. So, yes, it is directly to the frame of the trailer, along with the second chain that connects to the frame, aft of the bow eye area. And before you ask, the ball of chain was excess that has since been cut off.

 

[captain zac]

Re: Boat Sliding up Bow Stop Roller on Braking

First thing is
what is the weight of the trailer and boat?
what is the tongue wt.?
Is the toung wt. about 10% of the boat and trailer?
if not move boat until you get desired tongue wt. and move any rollers if need be.
loosen bow stand and move it to the boat so that the bottom of the top roller is touching the top of the bow eye.
tighten bow stand and you are good to go

Think of it like this
move the stand to the boat not the boat to the stand
The boat can only be in one spot to have desired tongue wt.
the stand can be moved to keep the boat from moving forward

Harry

 

[Mi duckdown]

Re: Boat Sliding up Bow Stop Roller on Braking

second. the transom straps, forcing the boat forward my .02

 

[Gearhead62]

Re: Boat Sliding up Bow Stop Roller on Braking

Boat wt is approx 3000-3500 lbs? (1987 Celebrity 21' I/O V8 350, Open Bow)
Tandem Trailer wt is approx 800 lbs?
Gas - When Full approx 450 lbs (50 @ 9 lbs / gal)
Total 4250-4750 ?? This is all a swag as I have never weighed officially

Tongue is light - feels like a 100 lbs on dead lift

***Tandem Axle*** When full of 50 gal gas (450 lbs), tank is over back roller assembly and that must decrease tongue weight

When tank is full, I notice a fair amount of tailend vehicle bounce ..... Pulling it w/ an '01 Navigator and back end sometimes feels slight pull up on bumpy terrain...That's why I am trying to correct the tongue wt, make it heavier, reduce upward play

 

[04fxdwgi]

Re: Boat Sliding up Bow Stop Roller on Braking

Boat wt is approx 3000-3500 lbs? (1987 Celebrity 21' I/O V8 350, Open Bow)
Tandem Trailer wt is approx 800 lbs?
Gas - When Full approx 450 lbs (50 @ 9 lbs / gal)
Total 4250-4750 ?? This is all a swag as I have never weighed officially

Tongue is light - feels like a 100 lbs on dead lift

***Tandem Axle*** When full of 50 gal gas (450 lbs), tank is over back roller assembly and that must decrease tongue weight

When tank is full, I notice a fair amount of tailend vehicle bounce ..... Pulling it w/ an '01 Navigator and back end sometimes feels slight pull up on bumpy terrain...That's why I am trying to correct the tongue wt, make it heavier, reduce upward play

Just answered your own question. Tongue weight should be between 330 and 475 pounds, if your weights are correct. 100 lbs is way too light. Move boat forward on trailer until you achieve the recommened weights, then move winch stand to meet the bow. You will notice a huge improvenment in the way the boat trailers. Plus the transom may then sit where it is supposed to over the bunks. Hopefully the trailer is long enough for this to be corrected.

 

[captain zac]

Re: Boat Sliding up Bow Stop Roller on Braking

Now you are getting somewhere
It appears that you have plenty of room to move the stand foreward
but also appears that you will have to move the rear rollers foreward also
use this method to determine the tongue wt.
Bathroom Scale



http://www.etrailer.com/faq-how-to-determine-trailer-tongue-weight.aspx


It also looks like you can take and jack up the stearn so you can move the rollers foreward

Harry