Boat Trailer Conversion??

wmgeorge · Dec 20, 2007

I've got a chance to buy a used tandem axle boat trailer... cheap. Said he hauled a 2000 lb boat trailer and it was not even to the capacity of the trailer.

Anyway, don't need much, just to haul JD650 tractor and loader + mower estimated weight at 4,000 lbs max. I'm going to look at it soon and just wondered, if the axles and tires were up the the load carrying capacity I needed.... has anyone here done such a conversion.

I have lots of time, two good welding machines and a small shop.

Ideas?

MrJimi · Dec 20, 2007

I see that your going to have some kind of deck/floor and an axle relocation and some real good tie-down points
Should be easy and fun and make sure you grind galvanize off before welding to it and recoat after there are some good galvy paints out there and check your wheel bearings and tires
Jim

chrpmaster · Dec 20, 2007

Had a friend do the exact same thing only with a smaller capacity single axle trailer. He added some cross members to the existing frame and added a flat deck of 5/4 treated lumber. Very strong. He hauled his Ford 8N a couple times with no problems. I don't know exactly how much weight that would be but I would think it would be over 2000 lbs.

Andy

Diamondpilot · Dec 20, 2007

I looked at doing the same thing. I am one of the few who like surge brakes and most boat trailers have them. Like stated above you will need to move the axles forward but there should be a lot of good parts there to start with if the price is right. Hopefully it will have dual 3,500# axles under it.

Chris

wmgeorge · Dec 20, 2007

Diamondpilot said:
I looked at doing the same thing. I am one of the few who like surge brakes and most boat trailers have them. Like stated above you will need to move the axles forward but there should be a lot of good parts there to start with if the price is right. Hopefully it will have dual 3,500# axles under it.
Chris

The tires in the picture look decent, but I'll need to check the load range. I can't see any rust and its inside his garage. He has an 18 ft fiberglass boat on it now... did I tell you its selling for $400?

Tig · Dec 20, 2007

The price seems right.

ampsucker · Dec 20, 2007

it's a good project. i've been involved in a few of these and i'll give you my take on the usual problem areas:

- axles have probably been submerged several or many times. depending on salt or fresh water, you'll definitely want to go over them and check for pitting/corrosion and repack. bearing buddies are a cool mod to add so you can just pump fresh grease into the bearings with a grease gun through a zerk.

- lights and wiring - same deal. depending on water and how often, may have to do a full replace.

- axle location if set up for a boat will be pretty far back since motor and gas tanks are usually in back of the boat. this makes for a very nice towing trailer (long tongue) but you may need to relocate forward as previously mentioned to get your 10% tongue weight. i would just recommend not going any farther forward than needed. if you know how you are going to load your tractor, you'll be way ahead of the game in getting this right. i can't emphasize enough how much your choice of axle location will affect the trailerability and ride of finished trailer.

- spring shackles will probably need new sleeves due to water submersion. also, check the u-bolts and centering tab for rust and replace as necessary.

- tires need to be carefully attended to. biggest problem with low mileage tires is dry rot from UV exposure. biggest problem with replacing them is finding the correct load range in the size rim you have. often times older boat trailers have the older and smaller sub-15" size rims. it's getting harder and harder to find these tires for the 14" and 13" rims. also, the less air volume, the less loading capacity on the tires. very important to match the load rating on the tires (x4) to the axle rating (x2) and ultimate load on the trailer. don't forget to subtract the actual weight of the trailer from the GVWH to get the actual size load you can carry. i weight my finished trailers empty at the local quarry scale (for free) to get my actual weight and finished capacity. tool boxes, gas cans and binding chains can add significant weight.

- if going with surge or elec brakes, don't forget that significant load shifts can occur during hard stops and your tire weight carrying needs to account for that (ie safety margin).

- surge brakes are notorious for leaking seals and low hydraulic fluid. at the least, you need to do a full fluid flush and replace with fresh fluid due to the hygroscopic nature of brake fluid. it's not the boiling point reduction so much as the rust on internal components from the moisture and breakdown of additives.

- carefully check out the hitch for wear, rust, etc. replace if necessary.

good luck and happy building!

amp

wmgeorge · Dec 21, 2007

ampsucker said:
it's a good project. i've been involved in a few of these and i'll give you my take on the usual problem areas:

- axles have probably been submerged several or many times. depending on salt or fresh water, you'll definitely want to go over them and check for pitting/corrosion and repack. bearing buddies are a cool mod to add so you can just pump fresh grease into the bearings with a grease gun through a zerk.

- lights and wiring - same deal. depending on water and how often, may have to do a full replace.

- axle location if set up for a boat will be pretty far back since motor and gas tanks are usually in back of the boat. this makes for a very nice towing trailer (long tongue) but you may need to relocate forward as previously mentioned to get your 10% tongue weight. i would just recommend not going any farther forward than needed. if you know how you are going to load your tractor, you'll be way ahead of the game in getting this right. i can't emphasize enough how much your choice of axle location will affect the trailerability and ride of finished trailer.

- spring shackles will probably need new sleeves due to water submersion. also, check the u-bolts and centering tab for rust and replace as necessary.

- tires need to be carefully attended to. biggest problem with low mileage tires is dry rot from UV exposure. biggest problem with replacing them is finding the correct load range in the size rim you have. often times older boat trailers have the older and smaller sub-15" size rims. it's getting harder and harder to find these tires for the 14" and 13" rims. also, the less air volume, the less loading capacity on the tires. very important to match the load rating on the tires (x4) to the axle rating (x2) and ultimate load on the trailer. don't forget to subtract the actual weight of the trailer from the GVWH to get the actual size load you can carry. i weight my finished trailers empty at the local quarry scale (for free) to get my actual weight and finished capacity. tool boxes, gas cans and binding chains can add significant weight.

- if going with surge or elec brakes, don't forget that significant load shifts can occur during hard stops and your tire weight carrying needs to account for that (ie safety margin).

- surge brakes are notorious for leaking seals and low hydraulic fluid. at the least, you need to do a full fluid flush and replace with fresh fluid due to the hygroscopic nature of brake fluid. it's not the boiling point reduction so much as the rust on internal components from the moisture and breakdown of additives.

- carefully check out the hitch for wear, rust, etc. replace if necessary.

good luck and happy building!

amp

OK well I found out this trailer has 13 inch tires, said the rating is 11?? so I'd need to actually See the trailer as this guy is mentally challenged, also has problems reading a tape measure. The other big problem is no brakes... so I'm assuming 2,000 lb axles, vs 3500# once again the guy is no help. Brakes I can install if it has a name brand axle, I'm assuming anyway... but can that tire size be used?? Max load on trailer 5K, so I'm thinking 7,000 GVW. How close am I on this thinking???

Diamondpilot · Dec 21, 2007

I think I would pass on it. By the time you buy axles, wheels, tires, brakes, steel, wood, on and on you could buy a good trailer ready to go. I bought a 2003 16'x6.5' tandem axle 7000# trailer with spare, brakes on one axle, and winch for $950. You will have near that in this conversion.

Chris

wmgeorge · Dec 21, 2007

Diamondpilot said:
I think I would pass on it. By the time you buy axles, wheels, tires, brakes, steel, wood, on and on you could buy a good trailer ready to go. I bought a 2003 16'x6.5' tandem axle 7000# trailer with spare, brakes on one axle, and winch for $950. You will have near that in this conversion.

Chris

Thanks Chris... Still looking for one like yours...

AndyMA · Dec 21, 2007

Surge Brakes aren't legal anyway. People get away with them but they do not meet the DOT regulation that the trailer brakes need to be indepently operably from the operators position. I'd hate to loose all my assets as a result of an accident resultng from using surge brakes.

See "SURGE BRAKES

However, there have always been questions about the actual legality of surge brake systems. DOT regulations specify that trailers with brakes must be fitted with an actuator that allows the tow vehicle driver to operate the trailer brakes independent of the tow vehicle brakes. In other words, he must be able to actuate the trailer's brakes without stepping on the tow vehicle brake pedal. Surge brakes do not offer this feature. They work using the deceleration force present as the tow vehicle stops. When the driver applies the tow vehicle brakes, the surge brake coupler's internal master cylinder compresses against the coupler body, forcing brake fluid through the brake lines to the wheel cylinders which forces the brake shoes against the drum (or pads against the rotor, if equipped with the newer disc brakes). If this sounds like a description of how the tow vehicle's brakes work, that's because surge brake systems work very much like car and truck brake systems. Unfortunately, there's no way for the driver to independently apply the trailer brakes in case of emergency. Are surge brakes legal? Technically, no — but that's a "technicality" that's been overlooked for decades. Surge brakes are still very popular on marine and rental trailers, and probably will continue to be for years into the future. "

Andy

Skyco · Dec 22, 2007

ampsucker said:
bearing buddies are a cool mod to add so you can just pump fresh grease into the bearings with a grease gun through a zerk.

Common misunderstanding.

Bearing Buddies do not replace any grease. Their sole purpose is to keep pressure on the seals when the axle is submerged in water.
Grease still needs to be replaced periodically with the bering buddy contraptions.
The grease systems where a longitudinal hole is drilled deep into the axle with a cross hole behind the bearings and then a zerk on the end of the axle lets one replace the grease. In that case the grease flows through both bearings from behind then out around the zerk typically through a rubber plugged hole in the grease cap where the zerk is accessed.
There is no fresh grease being applied through a bearing buddy into anyplace that matters...there is no where for the old grease to go, unless you rupture the rear seal

Skyco · Dec 22, 2007

AndyMA said:
Surge Brakes aren't legal anyway. People get away with them but they do not meet the DOT regulation that the trailer brakes need to be indepently operably from the operators position. I'd hate to loose all my assets as a result of an accident resultng from using surge brakes.

They are no longer illegal under federal rules since earlier this year.

"American Rental Association
March 7, 2007 (MOLINE, IL) - After more than 10 years of struggle, rental businesses can finally declare victory on surge brakes. The U.S. Department of Transportation's Federal Motor Carrier Safety Administration (FMCSA) in Washington, D.C., announced the publication of their final regulations that will allow surge brakes on all small and medium-sized trailers, even those used in interstate commerce. The new final rules are effective 30 days from March 6, 2007, which is April 5, 2007."

There may still be state laws that ban them in some states but many states never did ban them. Now federal rules make them OK on most trailers.

Marlowe · Dec 31, 2007

Skyco said:
Common misunderstanding.
Bearing Buddies do not replace any grease. Their sole purpose is to keep pressure on the seals when the axle is submerged in water.
Grease still needs to be replaced periodically with the bering buddy contraptions.
The grease systems where a longitudinal hole is drilled deep into the axle with a cross hole behind the bearings and then a zerk on the end of the axle lets one replace the grease. In that case the grease flows through both bearings from behind then out around the zerk typically through a rubber plugged hole in the grease cap where the zerk is accessed.
There is no fresh grease being applied through a bearing buddy into anyplace that matters...there is no where for the old grease to go, unless you rupture the rear seal

Bearing Buddies are a boat trailer thing. You are absolutely correct that they do not replace grease in the bearings, but what they do very well is to prevent water intrusion into the hub assembly. They do this by holding spring pressure on the grease inside the hub. The beauty of this situation is that a hub will warm up a bit as the trailer is hauled on the highway. When that warm hub is submersed into water at the boat ramp the rapid cooling will form a vacuum inside the hub. Even a new seal is not designed to prevent water from being sucked in when a vacuum exists inside the hub. That's where the spring pressure of a Bearing Buddy is the cure. The Spindo Seal system with the hole through the center of the spindle for greasing works great for re-greasing the bearings, but it is pretty much useless for preventing water intrusion. They are two different systems with two very different purposes.

By the way; I have a boat trailer conversion utility trailer I did a couple of years ago. It has a single 3500 lb. axle under it. The deck size is a generous 12' X 6'. The load rating is fine for material and mulch, but the tractor would be way too much. The axle, springs, lights, and tires were fine, so the investment was minimal. I bought a few pieces of iron and the rest of the material was laying around the yard anyway.

ampsucker · Jan 2, 2008

thanks for the edumacation on bearing buddies! i've always had them on my trailers but also, i must admit, most of my rear seals where either blown or were on their way to being blown by the time i got the trailers! so, i guess you could say, in my application, i was able to sort of grease the bearings from the front by squeezing old grease out the back ;-)

i'm sure you're right about it not working if you have good inner seals. it only keeps pressure on during submersion. i go ahead and give them a pump or two every time i'm headed out on a long trip just to be on the safe side. maybe that's how i blow out my seals??? i much prefer having the illusion that i'm doing something beneficial even if it's not actually helping much.

something else i always do is feel my hubs when i stop for gas. a warm or hot hub is always a tip off that bearing failure is imminent. doing it by the side of the road is a very dirty job and if they get too hot and sieze, you'll be buying a new axle, so i figure it's better safe than sorry.

on the topic of surge brakes, never been a big fan. like i previously posted, they are a pain to maintain and without proper maintenance, you don't have much braking power. and, then there is the issue of activation. surge brakes do you little or no good in slippery conditions. if the tow vehicle can't can't enough traction to slow down and force the trailer inertia to activate the brakes, you don't have trailer brakes. ditto with sway. stepping on the tow vehicles brakes when you have a bad sway can induce a jack knife. the proper thing to do is activate the trailer brakes to slow down to a safe speed to get the sway under control. can't do it with surge brakes.

i wouldn't doubt the is a strong rental lobby to get this surge law passed, but i'm not convinced it's made the roads any safer.

Skyco · Jan 2, 2008

Marlowe said:
That's where the spring pressure of a Bearing Buddy is the cure. The Spindo Seal system with the hole through the center of the spindle for greasing works great for re-greasing the bearings, but it is pretty much useless for preventing water intrusion. They are two different systems with two very different purposes.

Well there is a little pressure maintained by the rubber caps..I have several trailers with the drilled axle and the rubber caps. After towing you can see the caps bulged out a good bit from internal pressure buildup. After cooling they drop back down, so there is some pressure when hot and dunked in the water, but not as much as Bearing Buddy types.
The biggest failure I've seen with Bearing Buddies is over greasing, some of them have an indicator line on the internal piston to show one when to stop pumping, over grease and pooch the rear seal and trouble is on the way

Diamondpilot · Jan 2, 2008

Over greasing is a major problem with Bearing Buddies. The last four sets I bought have a hole drilled in the side wall so when there is enough grease the extra comes out (all over your rims). A good way to check if there is enough grease in them is if the plunger will rock with finger pressure you are good.

Chris