Bigger Hammer

I posted about this on another forum a year ago, and wanted to follow up with my experience since it's been a year. And then I got this personal e-mail from Wiley inviting me to post more often. So the first part of this was written a year ago, with my follow up appended... First let me state that I have no connection with AirTight hubs, and at this point don’t have a final opinion of their product. That will be determined by how long my trailer goes without leaking hubs. I have a 4 year old, triple axle, 15K lbs GVW trailer. Trailer manufacturer is unimportant, as I never contacted them about any of the problems I’ll describe due to distance and time. Very early on my trailer was leaking from one of the grease seals; shortly thereafter two of the other seals began to leak. Over the last 4 years I’ve replaced these seals at least 4 times, they would typically go for a few months and several hundred miles before the new seals would start to leak. Last year, going to my third set of seals, I looked a bit closer at the spindles to see if I could figure out what was going on. I’m no expert in these things, but what I saw didn’t look anything like I expected. I found that the sleeves the seals ride on had manufacturing defects, axial grooves or creases, that looked like they would prematurely wear the seals and allow leakage across them as well. When I replaced the seals last year I polished the sleeves to try to reduce/smooth out the creases, but was afraid to polish them too much because I was afraid of reducing the sleeve diameter too much. What I ended up with was much smoother than what I started with, but the creases remained. After several ~100 mile trips we left for south Florida, and before we got to our destination the seals were leaking again, slinging grease all over everything. After returning I bought a replacement set of sleeves to replace the original equipment sleeves. The truth is that I didn’t look at the new sleeves until I was ready to replace them. The new sleeves also had the same grooves or creases, but far fewer than the originals had. I didn’t want to go through this again, so I started looking for other alternatives. AirTight Hubs (http://www.airtighthubs.com/) has a system that seemed like a big improvement over what I had. A machined ring/bushing, approximately ¼” larger in diameter than the original equipment sleeve, is installed on each spindle to give the seal a perfect surface to ride on. The seals supplied are manufactured by Chicago Rawhide, I looked up their applications online and they fit something on a commercial, heavy duty, truck. I wasn’t convinced about the pressurization system since I’ve been perfectly satisfied with the past few trailers I’ve had with standard Super Lube-style bearing/hub lube systems. I figure that if the pressurization system doesn’t work I’ll just go back to the standard plugs, I’m really only looking for a reliable rear hub seal. I ordered 10 sets of the AirTight Sport Hub Kits to fit my trailer, but not all at once. The Sport kits are the cheaper versions without the pressure gauge, just a standard cap with a rubber bellows plug, and inflated with a ball inflation needle. 6 hubs on the trailer, 2 spare hubs, and 2 spare spares. I bought 6 first, and was impressed enough that I decided to get the rest of them. I actually found that West Marine had the best deal online, on a closeout sale. The photo below is of one of the original sleeves after it was removed. Recall that this is after 4 years of service, and after having been polished last year. The wear from the seal is clearly visible. This is one of the replacement sleeves that I didn’t use. Certainly nowhere near as bad as the originals, but I really don’t like changing seals… The biggest pain about this whole thing was the grease all over everything where the seals were leaking. I’ve got Kodiak all stainless brakes. Strangely, the tabs on the original brake pads were bent on installation, apparently to help retain them. There’s no need for this, the new ones went on without being bent like this: I ended up replacing several sets of bearings. In this picture I was trying to capture the staining of the bearing rollers, they were not a consistent color across the length of the rollers, so they were replaced. Any set that had any discoloration or evidence of rust anywhere was replaced. To remove the original sleeves I cut into the original sleeves with a cutting wheel on a Dremel tool, then rapped them with a hammer and chisel to break them off. The spindles were cleaned up with scotch brite, then sprayed with brake cleaner and wiped clean. The kits come with retaining compound which is spread over the mating surfaces of the spindle and sleeves, or what AirTight calls shims. In hindsight I should have checked to see if the bushing (the ring the seals ride on) would fit without the sleeves ‘cause they were a very tight fit. I used a galvanized pipe and coupling as installation tools, along with an old inner bearing, to seat the sleeves/shims. They are really the same sleeves as were originally installed for the seals to ride on. Funny, other than some minor rust these parts from AirTight were completely free of the creases. The sleeves are then cleaned, and retaining compound applied to the mating surfaces of the sleeve and bushing. The bushing then goes on over the sleeve, just as the sleeve went on the axle. As I said above, it’s a very tight fit, took a good size hammer. The bushings are supposed to be recessed about 1/8” past the end of the sleeve, and the directions say to use a brass or aluminum punch to move them back. This didn’t work well for me, so I ended up using another bushing, along with the galvanized pipe and hammer, and inner bearing, to do this. This is a bushing fully installed. You can see where the grease comes out from the spindle, this needs to be opened up with a punch to allow the grease to get to the bearings after the sleeve/shim is installed. Injecting some grease into the spindle will force any debris or retaining compound out where it can be cleaned away. The directions say to use retaining compound to seal the seal to hub, I chose not to. The supplied seals are coated with a sealing compound on the outside, and after having to remove a cap that was “retained” I’m sure that trying to remove the seal in the future would be a real PITA. I put everything back together, and everything looks like it’s working as designed. Although I’ve only taken very short trips, some of the hubs have been assembled for several weeks with no sign of leakage. This is what an assembled hub looks like. The bellows on the plug expands to indicate the pressure in the hub, less than 10 psi is required. If the bellows goes flat it’s an indication that there’s a leak. Some of mine have been holding up for several weeks now. Some thoughts: One of those “Why didn’t I think of that before?” moments: A few minutes with a Dremel tool eliminated the burrs on the inside of the caps that so easily slice your finger when you scoop the grease out of the cavity. A few other things to watch for: 1) The threads in two of the brake caliper mounting brackets were stripped, one of the bolts couldn’t be tightened even snug. I don’t know what caused this, as they were both on hubs that had never been disassembled 2) Three axles, 12 bolts holding them to the trailer frame. Only one was snug, the other 11 were loose. One of the hubs went flat after the first night it was installed. Troubleshooting guide suggests that a seal replacement may be required, I just lubed the plug better and reinstalled it, so far everything looks good. I used zinc plated caps rather than the chrome plated versions that came with the kits. If anyone wants 10 chrome plated caps for shipping costs let me know. I’ve now got about 300 miles on these, and they’re retaining air much better than I expected. And still no leaking grease. The real test will be the upcoming trip to S. Florida in a few weeks. I’ve got no other explanation for this than how tight the spindle nuts may have been and the ambient temperature not getting so high yet, but my bearing temps have dropped from 130 – 135 F to 110-115F. So now the follow up... It's been a year now, and I've just completely replaced all the grease in all 6 hubs, and flushed out all of the old grease, in preparation for our annual trip down to Ft Lauderdale and across to Bimini. Knock on wood... For the first time since I've had this trailer I've gone a full year without any sign of blowing a grease seal. All of the rubber covers are holding pressure, it's very rare that I need to pump them up. There was no visible sign of moisture in any of grease that was flushed out. Gotta call this a huge success for me, I've spent way too much time pulling hubs to replace seals.

Galvanized wheels will get dark quickly even after cleaning. If you're looking for something that will make them surprisingly bright, for a short time, try Meguiars Hot Rims wheel cleaner. I used some on my galvanized wheels a while back to remove some grease, was very pleased with the results.

Autotether head unit in the purse or pocket, a FOB on each one of the kids. Maybe reduce the number of idiots leaving their babies locked in parked cars. Or kids left at the rest stops on the Interstate. Bill

This is what I'm using: http://shop.easternmarine.com/index.cfm?fu...;categoryID=194 Bill

Do you need the wheel? I took mine off, replaced it with a metal foot. Helps keep the trailer more stable. If the jack is not tall enough you could add a support (4x4 or 6x6, for example) underneath it. Iv'e been doing that just to minimize the wear on the jack, and how long it takes to wind the jack to the ground to pick up the tongue. Bill

I went through several console upgrades on my last boat, and using Starboard makes future changes very easy. If you decide you want to add or delete something in the future you just replace the Starboard panel. I've read that it expands and contracts too much with temperature for this application, but that wasn't my experience. I agree with the positive comments above. Bill

Experience has taught me that a water pressure gauge is a necessity with an outboard engine. It may pee until the pump is completely dead, a pressure gauge will give you a warning of impending failure. Bill