Fan Hub Bearing…

Fan hub bearing lubrication…

Learning a new engine can take time, but the RV’ing forums help a lot with ideas about things that must be checked quickly during or after purchase. One of those things I learned about the Cat 3126e engine was that they mounted a zerk fitting in a difficult to access place on top of the engine. Used for greasing the rotating fan hub bearing. Most maintenance procedures by most shops and owners ignore it and it doesn’t get greased, leading to an early and costly failure. Winnebago compounded the difficulty of regularly greasing there with the poor design of the access hatch. The zerk cannot be reached from the bottom, so you must access from the top. And to do that, I had two technicians at different shops tell me that the bed needed to be removed. Well, BS. Takes 3-5 hours to remove and replace the bed, and owners of this model on the RV’ing forum tell me that it doesn’t need that for this job.

I didn’t find any maintenance records from the previous owner, so I don’t know at 70,000 miles if it had ever been greased. Dust in the engine compartment suggests no. Cat specs it should be greased regularly but I don’t recall how often at the moment. After this engine design, when they discovered people weren’t greasing it, they changed to a sealed bearing design. And the experts (Wolfe10 on think the greasable is better. I’m happy to hear that as that’s what I have. Other forum posts indicate Cat is asking that the sealed bearing be replaced every 40K miles. I’m not certain of that and it doesn’t sound reasonable but if you have the sealed bearing, you should check that.

I happened to bump into a RV tech living here in this campground, told him what I needed and arranged for a visit. Before the tech arrived at his appointed time, I found that I only needed to remove those three bolts shown below, and the lid pulled right off. Some techs think there’s more bolts in the back of the cover (two techs told me that)…which is one way they justify disassembling the bed stand. Wonder how many shops neglect to change that 3-5 hours back to 1 hour after they discover they screwed up?

OLYMPUS DIGITAL CAMERA Here’s the lid. Not all that large, but surprisingly heavy.OLYMPUS DIGITAL CAMERA

Here’s a shot that shows that removing the bed frame really wouldn’t gain much work room. Maybe a couple inches at the top.


My first look at the engine.

There’s the back of the surge tank on the top left, the fan shroud and fan, and a few hoses visible. But you can see how difficult it would be to work on the engine. Yikes! No room!

But when you climb a little ways into the bed frame, you can see there may be enough room for some things, like hose replacement, the alternator, the serpentine belt, filter, etc. It’ll be expensive to have a shop work on this for sure. You’d want a skinny and short tech to do the job too. A large tech just wouldn’t be advisable. Looks like most major work will require the radiator be removed. Not fun at all as that would probably require removal of much of the back of the RV as well.

OLYMPUS DIGITAL CAMERA And a look at the back of the rad shows an accumulation of road grime. And dust covers the engine. Also, there’s lots of rust.

Well, one thing at a time. The tech arrived, looked at the opening and he thought the bed frame should be removed, I insisted it didn’t, so he and I moved the mattress into the kitchen as I wasn’t going to let him tear apart the bed frame. He figured out he could remove the gas struts to get the bed base up higher, used a broom stick to prop it open. Now with as much room as he’d ever get with this design, he crawled around on the engine searching for the zerk. Even crawled around under the engine. No luck. So off he goes to Camping World to look at their books for the engine. Turned out he use to work as a tech at the CW just across the street from where I was parked. If I’d known that, I probably wouldn’t have hired him to begin with, as CW techs are usually very poorly trained.

While he was gone, I took some more pictures.OLYMPUS DIGITAL CAMERA OLYMPUS DIGITAL CAMERA Finally, the zerk is discovered, and the tech points out it’s position to me so I’ll know where it is when I need to regrease it next time. It’s necessary to rotate the fan a little to get it into a position where you can see the zerk. He gives it a good 8 squirts of grease. It’s a small gun so the squirts don’t hold much. A big grease gun, I’m told, only gives it 3 squirts. It’s position is around 3″ behind the fan.OLYMPUS DIGITAL CAMERAI only paid the guy $20/hour for 2.5 hours work so it was worth hiring someone to do it for me. A total of $50, includes grease. Compared to what a $125/hour shop would have charged? I’ll take it.

Next time, I’ll know exactly how to do it and will likely hire a mobile tech. A shop would just charge far too much for this easy job. And I’ll let the tech know it’s only a 1-1.5 hour job.

Here’s a photo of the front of a Cat 3126 engine sans rad and fan. The fan hub with the 6 fan bolts sticking out is in the middle of the engine, the zerk fitting just on top of that. With this example the owner had added a hose extension to the zerk fitting in order to grease it with less difficulty. I may try that later on.

Engine What’s up next? I’ll need to find a RV campground, or a wash facility where I can spray Purple Simple Green all over the engine & compartment, and the rear of the rad, let it sit, then low pressure wash it off. That’s going to be a chore. Don’t know when I’ll be able to get to that. Took almost two years to find the appropriate place for that kind of thing in my travels when I needed to do that to the Bounder.

Following the cleaning, I need to treat most of the exposed metal in there and on the undercarriage to stop any rust, and for that job I need to find a RV park where the RV pads are cement or blacktop and I can use my creeper. Ahh, the joys of full time RV’ing.

My Bounder had rust all over the undercarriage when I bought it, and I had several shops, where I went in for estimates of jobs, tell me, “Oh, that rust is going to make the job harder so it’s going to cost you extra, and you need to replace this and that!”. And it wasn’t true. It’s a scam, just like telling people they need to turn the rotors every brake job. You don’t.

I can attest that wherever I had a shop work on the rig, there was never any extra time caused by rust. I watched. Usually, extra time was taken by the shop because they didn’t know what to do or how to do it and they’d have to spend time researching. That’s why I always try to find out how a DIY’er does something on their similar rig before going to a shop.

Anyway, my point about rust is that these chassis are soooo stout, the metals soooo thick, that rust would never penetrate anything important in a thousand years. Some rotating parts might be adversely affected if the road salt splashed directly on the rotating shaft, perhaps, perhaps not. If you’re unlucky enough to be in a part of the country where they often salt the roads, and you’re foolish enough to drive your RV through it often without immediately spraying off the salts, then it’s quite possible you’ve had more rust caused problems than the average RV’er. From the looks of my Winnie, the previous owners did drive on salted roads, but not often.

At this point, I’m not worried about all the rust under my Winnie. Only time will tell if I bought a rust bucket liable to fall apart in the near future, OR, if it’ll give me the 10 years I’m looking for…after I stabilize the rust.

Jan. 2018

I did need to clean my engine compartment in preparation for the surge tank replacement that I did and here’s what it looked like afterwards…

I had a spray bottle of Simple Green Purple that I sprayed all over the engine compartment, let it sit for a while, than lightly dampened it. Used my scrub brush wand to get all the nooks and crannies afterwards and than finally a through rinse.

While I was at it, I also did a double treatment of the backside of the rad, spraying it with Simple Green Purple and rinsing it off well, twice. I noticed an immediate change in how high the temperature gauge went on the dash meter the next time I drove. At least two needle widths less than before. I can still see some crud plugging the fins on the rad and over the next couple years I’ll do the occasional wash and rinse. I’m not trying to make it a clean as it was when new, not sure that’s even needed. But I don’t want the engine to overheat either. Hopefully, now that I’ve cleaned it, and with the lowered amount of oil I use in the crank case, (less chance of it blowing out of the slobber tube, mixing with road dirt and clogging the rad) the rad will stay reasonably clean and help keep engine temps low as I drive up and down mountains.

One Response to Fan Hub Bearing…

  1. Larry Allen says:

    I seen your response in the Good Sam site about the fan hub bearing. I have purchased the extension for the grease zerk and trying to install it. In the photo of the newer engine with the extension installed I can see a small adapter between the hub housing and the tube provided with the extension kit. Do you have any info on who did the installation or who may know what and where I can get the adapter. Grease Extension didn’t do it and knows nothing of what it is.

    Sorry, it was too long ago for me to remember where I found that picture. I am pretty sure it was from someone’s blog but I don’t have any idea where I found it.

    Oh, wait, yes I do: Link to forum…

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