Steel trailer rusted right through after only 3 years

[Rising Star]

I keep my MacGregor 2006 model on the factory (steel) trailer at a boatyard. I live in Hong Kong and flush the trailer after each launching. After only 3 years, the drawbar rusted right through where it meets the "V". Frankly, I am shocked that this could happen so quickly. It has really only started showing visible signs of rust in the past 12 months, and I have attacked it with rust converter and anti-rust paint (hence the grey and red coloration). But it obviously rusted from the inside out.



Luckily, it snapped at the bottom of the ramp when I was trying to retrieve the boat.

Looking at the new aluminum trailers, it still has the steel drawbar.

[kmclemore]

Unfortunately, this is a known problem with Mac trailers. I wish the factory would drill a drain hole near the "V" junction so that you could properly flush the drawbar, but i suppose they are worried about a strength issue.

To anyone in a salt-water environment, I would suggest drilling a small hole, about 3/8" or so, in the bottom of the drawbar, as close to the "V" as you can make one. Then flush the drawbar with clear water every time you dunk it. if you don't, salt water will accumulate in the bar, getting more and more saline as time goes on, and it won't be long before you'll have a failure.

[curtis from carlsbad]

Called Inman at the factory this morning over a leaky port-a-potti issue,decided to bring up your problem as I have a new alluminum trailer and was worried about the steel portion.He told me on the new alluminum trailers that it can fully drain as there is a large square opening on the rearmost portion of the steel section where it meets the alluminumsection.I went out to the trailer,crawled under and sure enough Inman was right. Now I will flush under there with a hose and give it a wd-40 bath as someone suggsted in a previous post.BTW I already have rust buildup coating the entire inside of that roughly 5 foot section of steel and the trailer is only about 6-8 months old by my estimation.( I bought boat about 4 months ago).First I am going to wire brush as far as I can get into there.Then I will follow the advice of the previous gentleman's post and do a post launch flush(pour over) on the steel parts,axle and wheels using some empty plastic 1 gallon milk jugs and quick spraydown with wd-40 ,then after the retrieval of the boat(even if only 8 hours later) I will use the free hose at launch site to wash entire boat & trailer and after boat is dry at home another spraying of wd-40 and also on topside stainless steel fittings.Lastly ,cover boat at home after water evaporates .If I have made any mistakes in my planning please respond to this post. Curtis Becker

[johnnyonspot]

One of the first tasks I was handed upon checking onboard the USS John Rodgers when I was in the Navy was to take the Nixie openings on the stern down to bare metal, prime and paint them. These are two holes in the stern through which the torpedo countermeasures are streamed and they get a lot of salt water exposure. I used a needle gun to bring them down to bare steel and then put on 2-3 thick coats of Formula 150 2-part primer that when dried was almost like a hard green rubber coating. I really slathered it on there since I did not want to be doing this job again. I covered this with white paint and when done it looked really good. I was on the ship for almost four and one-half years and all during that time I kept an eye on this paint job. Other than some very minor surface rust that could be rubbed off with a greenie weenie before touching the white paint back up there were never any rust issues or other issue at all. SO I gotta ask, is there not some high quality primer on the market one might apply to the inside of these trailer tongues to defeat the rust problem, at least for a while?

On Edit: I just googled the formula 150 2-part primer I used and found it on this site, which seems to have all kinds of different paints and primers available. It describes it as: "Polyamide Green Primer (Formula 150) For use where excellent adhesion is needed on solvent-cleaned steel or for a marine environment protective coating." This is also the stuff we used on the topsides underneath the haze grey, so you know its gotta be some pretty serious stuff. It can also be found here.

[Wind Chime]

I re-did our trailer while the boat was at anchor this past summer.

I used an electric grinder with rotary wire brushes and got as much rust off as possible. About 4 hours work. I was afraid to use a grinding wheel and expose all the metal. I then used 5 cans of black rust spray-paint from Home Depot.

I stood back and said "that looks great, good job" to myself. It's two months later now, and it's rusting already. Sounds like I should have used this 150 stuff.

[puggsy]

If a NEW steel trailer is hot dipped galvanised right from the start, it will last a lot longer than a aluminium one...
And you can buy galvanised springs and wheels for same...only the solid square axle cannot be dipped because the ends have been machined...for the bearings....



note the condition after seven years...

[The Mutt]

A good friend of mine is a steel specialist, he is adamant that the vertical weld at the V point is a built in time bomb waiting to happen, if I get what he said right the steel molecules re-arrange to vertical around this point where they should be horizontal from the original extrusion, similar to a perforation line on a piece of paper, he wants to put a 6mm plate on each side of the V rounded over on both ends so that there is no full line vertical, he also wants us to hot dip gal the trailer.

We're looking at getting it done next year.

Glenn

[Erik Hardtle]

I've owned both macgregor powersailors (19 & 26X) and had both factory trailers rust to an unusable condition in just a few years. Yes I live near and boat in salt water areas. Yes I did the sand, prime, paint every time I could but just couldn't keep up with the rust. Eventually I replaced both trailers with galvanized ones and haven't had to do much expect the usual wash down.

The last factory trailer (26X) actually snapped the axle from rust while on a bridge in traffic... not fun.

It was pricey for the replacements ($3000) but for my piece of mind, and especially because I trailer mine everywhere, I am pleased with the investment.


I would highly recommend saving now for a replacement with dual axles before the trailer rusts itself to death... and it will.

Erik
Knot Shore

[Kelly Hanson East]

Ive had seven good seasons with my 2002X trailer, but Ive always religiously dunked it in the Hudson (mixture of fresh and PCBs) after use in salt water. Axle seems strong from tapping and visual inspection, but Im not sure how well this really tells the tale...

[TAW02]

This problem is a real odessy, since this portion of the trailer never gets dunked. At least to my knowledge.

A few years back I purchased a dual axle trailer to convert over to haul my MAC25 with. Paid only a hundred dollars for it, and mainly because it was rusting out in the same area around the drawbar siderail area. How does this happen?

Like I said, how does salt water get in the drawbar in the first place. Especially on a MAC trailer that carries a low-draft vessel like the or the , that doesn't need to slip the trailer that far into the water?

Oh well, just some thought going on inside my head.

Big T

[LOUIS B HOLUB]

I once saw Mac X trailer failure at a mast up Marina locally, and the axle snapped where it's welded to the hub. If you notice, there is a "hollow" area underneath this weld site, and rust will form easily. The owners of this trailer had to spend the entire day, and next day, running around for parts, another axle, etc. It was a serious mess, and couldve been far worse if it occurred on a busy highway.

When we trailered regularly, I checked this weld site closely. The hub-axle site seems to be a seriously weak weld point on a Mac X trailer if rust is overlooked.

Since we now slip our Mac, the trailer is stored dry within my barn.

Suggestion: Check your hub-axle weld site, underneath.

[Rising Star]

To add to my original post, there is a hole at the end of the drawbar where it meets the cross "T" member. I had mistakenly assumed that all water would drain out of this hole. What I did not realize was that water was stagnating midway up the drawbar.

The other oversight I made over the last couple of years was paying attention to the lower parts of the trailer which were dunked regularly, not really thinking much about the front parts. The lower frame consists of open "C" sections, so water drains out and any rust is visible. But now I learnt my lesson.

I am getting this drawbar replaced with a galvanised piece, so hopefully, that will last a bit longer. But given the low quality of this trailer, I think that at some point, the whole thing will need to be scrapped and replaced, so not worth spending a lot on it.

[LOUIS B HOLUB]

But given the low quality of this trailer, I think that at some point, the whole thing will need to be scrapped and replaced, so not worth spending a lot on it.

For safety's sake, and if your trailer has already failed once, one cant help wondering if it may have other potential problems, and somewhat risky to tow-loaded on long trips.

[opie]

I bought my galvanized trailer from a guy in Maryland who only used a few times in fresh water. I used a Hot Galvanizing Silver Paint from the home improvement store, and it said it was to prevent rust on galvanized items. I used it alot, thinking more was better. On close inspection recently, after three years, a screwdriver poking around each trailer bolt and clamp resulted in big flakes of paint and rust coming off on every bolt I painted. All I had done with that Hot Paint is to make little rust incubators around each bolt. What a mess. I found two bolts I had missed under a fender and without that stupid paint on them, they were in great shape with only some slightly rusty color here and there. WD40 or axle grease are going to be my only preventive covering from now on..... after I replace everything. $$$$