This topic had already been well cover by others. Especially the threads started by craneman and Sven, were most helpful. Thanks, Gents. 8)
hydraulic fan motor (http://www.foreforums.com/index.php?topic=27326.msg223479#msg223479)
Replacing the radiator (update) (https://www.foreforums.com/index.php?topic=30623.0)
That being said, I'll only cover what I did differently. Technically, we're not "rebuilding" the motors. This is a shaft seal replacement that, done in the conventional way, requires a $120 "rebuild kit", for each motor. I took a pass on the captive audience priced kits. Let's just pull the seals from the assembled Sundstrand motors and install new seals. I was going to make a seal puller but, once I got a look at the seals, decided not to do that for only two seals. The seals have a rubber coated OD and pull/install easily.
The solution was very easy: Drill two holes, 180 degrees apart, through the face of the seals with a 7/64" drill. Partially screw a #6 sheet metal screw into each hole (Anything more than 3/4 turn will be too much) . Using an appropriate block of wood as a spacer, and a flat steel bar (medium screwdriver), gently pry on the screws, alternately, until the seal is out of the bore. The first one took about 10 minutes to figure out what I needed, and to pull the seal. The second one took about 2 minutes.
A few things to be aware of:
Do not drill beyond the metal embedded in the seal. (Don't drill into the motor housing!)
Do not damage the motor shaft with the drill or the screws. (I made a sleeve from aluminum flashing to help protect the shaft)
Drill the holes biased slightly towards the housing bore, rather than the shaft. (I drilled using two of the six rectangular marks in the seal as a guide)
Seals I used: https://www.mcmaster.com/1199N313/ (https://www.mcmaster.com/1199N313/)
Greg
Excellent technical post! Concise instructions + clear close-up photos. Valuable addition to our Forum knowledge archive. ^.^d
Greg slight variation of how you did this has worked well for me. Instead of drilling I use a small prick punch and tap a very small hole in the soft metal part of the seal then insert a self starting drywall screw. I actually have a small slid hammer puller made to slip over the screw head to gently tap the seal out. Great post. I will order seals for future install.
Thanks Scott
Amazing work. I know I can't do this sort of thing in my older age but can pass it onto my mechanic. Thanks
The perfect photos! Your DIY could make it in a shop manual.
Pierce
Scott, I like your technique better than what I did. Punching the holes should generate no chips that could get where they shouldn't be. (Inside the motor) I should have mentioned that I gently blew the few chips away from the area before pulling the seals. Then I inverted the motors (Shaft facing down), and squirted mineral spirits into the seal bore, to flush any debris out. Then I blew compressed air into the case drain port, and repeated both for good measure.
Greg
I had to buy the seal kit to get the seal information for the first motor, then just bought a seal for the other one. Now that the seal info is out there and this post on the easy way to reseal, more DIY's can take place. The motors can come out without removing the radiator.
Thanks for sharing your approach for pulling the seal and doing the replacement. Not sure I trust my drilling skills enough to avoid drilling into the housing. Protecting the shaft is a smart idea.
Anyone used puller like this? Video makes it seem easy of course.
Lisle Shaft type seal puller (https://www.amazon.com/Lisle-58430-Shaft-Type-Puller/dp/B000FPYW4K/ref=asc_df_B000FPYW4K/?tag=hyprod-20&linkCode=df0&hvadid=312065537890&hvpos=&hvnetw=g&hvrand=1852213786674566830&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9013543&hvtargid=pla-633100651832&psc=1)
How to use video (https://www.youtube.com/watch?v=BtsGU2nLrJg)
@ craneman,
I didn't pull the radiator, since the PO had a new one installed a few years ago, and it's in like new condition. The CAC appears to be the original, and is in decent condition. Both motors had a small leak when we bought the coach. The front motor developed a pretty bad hemorrhage on our last trip to TX. I noticed she was marking her spot the morning after we pulled into Xtreme. I did pull everything else to clean and detail. Putting it back together, with clean parts, has been a much more pleasant experience than the grimy disassembly. I'm hoping to finish this project over the weekend .... and move on to the next one :o
Greg
Sure is nice having smart people like you and crainman doing all the hard work and letting me make a simple job almost as thou I had done it before. Thanks for all the great posts and information, part numbers. This should all be included information in the maintenance manuals I wish we had.
Scott
Greg how did the removed seals look? Sharp inner sealing lip? Or worn down. Any shaft wear?
I am making my records from all i can find. Thank you for another huge CB saver!
Mark
If I were to order these seals as spares or for future use, would I need two per motor or just one?
Richard
Good question and what other seals are needed. The kit in Craneman's post look like there were some o-rings and other seals needed to do the job.
Perfect idea "FT shop manual"...Chuck???
Those would be to solve internal leaks or to replace internal parts.
The seals didn't look too worn but at 21 years of age, minimum, it's no surprise that there was leakage. The backup washer that goes between the seal and the snap ring was missing on the front motor. It could have been a contributing factor in the front motor leaking more, but I can't say for sure.
There was no measurable wear on the shaft where the inner lip rides. There was some light rust on the shafts, just outside the exclusion lip of the seals. I polished that off with 1200 paper before removing the seals. It wouldn't have affected the seals as installed, but might have caused some minor damage to the lips during installation. (I could have put a mylar wrap on the shaft during seal installation to negate any damage)
Greg
Was the sharp edge still visible on both surfaces?
The inner lips had a slight flat where they would have been sharp when new. I didn't measure it. The exclusion lip looked pretty sharp
Thanks Greg I rebuilt dirt engines and the seal sharpness is the key. Not sharp I toss them
I want to give THANKS to everyone on this thread, especially Mister Ed (Greg) for all the information here.
My shaft seal was leaking and I decided after reading this thread to give it a shot. Started by degreasing everything, then blasted it all with brake cleaner to clean as much as I could.
Made sure I had caps and plugs to cover the lines as I took everything apart. Only lost maybe 2 quarts of hydraulic oil.
Greg was a big help with info on sourcing the seal, removing the fan hub, and just inspiring me to do the job. As I've stated in other posts, this Forum is Great ! Here's a pic of my seals (new & old) and my finished job with seal, washer, and clip all back together.
Now just got to put it all back together !
Did you do the pump or the fan motors?
The seal on the fan motor shaft.
Did you pull the radiator to get to the motors? Or did you pull them with the radiator in place?
Did not pull the radiator. I removed them from the back side. It really wasn't that difficult of a job, just a little messy. I did drain the radiator and removed the lower metal radiator pipe that runs along the bottom of the radiator. It might be possible to pull the motors without removing that pipe, but pretty cramped in there with a lot of lines.
While I was doing this, I went ahead and flushed the radiator, and drained the hydraulic oil and did a filter change.
I did the whole project over a couple of days, but if someone really wanted to stick to it, could do all in a days work.
I have given it a test drive since finishing, and everything is clean and dry. Looks like it was a success!!!
Motor oil and filters-check, Radiator flushed and all new antifreeze-check, Hydraulic Oil and filters-check. Same for Generator.
Going to do all the Fuel Filters this weekend and will be ready to go. I will say, it did give me a feeling of accomplishment
Thanks again to everyone for their tips and information..
My Hero !
Thanks for the reply.
So the fan motors are on the preventive maintenance list and the steering gearbox. Getting closer. Getting everything brought up to speed is a great feeling. Glad you got em done.
Scott
Just finished, resealing the fan motors. Not a particularly technical job. Just dirty and 15 gallons of coolant and 5 gallons of hyd oil to deal with. Takes longer to clean and drain everything. Also helps to have a friend that doesn't mind getting dirty to help.
Can you post brand of motor and part number and source,thanks.
Sun strand motors looks like, no part # I could see. The shaft seals are 20x30x7mm. Got mine off of Amazon.
One off the list.. It seems never ending ^.^d
I saw this posted earlier in the thread and had bookmarked it
Fan Seal (https://www.mcmaster.com/1199N313/)
But I still have not found a source for the rebuild kit. I am still researching. Seems there is a lot of different motors out there and I have to figure out exactly which mine is. I had this bookmarked too.
Fan Motor Breakdowns (https://hydraulicpartsxchange.com/breakdowns/)
I want to be prepared when I replace the radiator and have them on hand just in case.
I just replaced the shaft seal in mine. I didn't see any need to open the motors up. The shaft seal where just hard from age
I did the same as Bruce and just changed the seals. There is no reason to open the motor.
How did you guys remove old seals? I have my radiator out and plan to replace the fan seals while the motors are still in the RV fans and brackets are strapped into should mount back up to the radiator when I get it back
Thanks
Mike
Remove the fan and fan retainer and drill a small hole in the old seal and screw in a metal screw
and pry the seal out and reinstall the new seal. Put a little grease on the seal lip before installing.
Thanks
Here is a post with some pics that might help.
The Project Coach (https://www.foreforums.com/index.php?topic=47103.msg478267#msg478267)
Mike
hey Mike I use a small awl and punch a small hole, use a small sheet metal screw in the hole, then a pair of pliers to pull the seal. The seal comes out very easy. To install the new seal use a deep socket or other suitable tool that will fit inside the body over the shaft, start the seal then start the snap ring, lightly tap the snap ring until it snaps in place. That way the seal goes in straight. I just don't like the drill method you have to be very careful not to nick the aluminum motor body.
Thanks Bruce, going to tackle that next week, the hydraulic lines are kind of nasty so will be cleaning and inspecting them too ,a line must have burst at one time, or maybe just oil flung from the weeping seal but they are crusted up.
I cleaned the motors and lines up twice with a pressure washer and still went through 3 shirts. Also the hydraulic fittings are JIC. If go to your local Hyd shop they have inexpensive plastic caps and plugs for the fittings helps keep the dirt out and the drips down. It will take 7 # 12 caps and plugs one #6, 5 #4
Although these are flexible lines that was when they were young. They are twenty plus years old now and have taken a set to there current position. They will flex but can be damaged if flexed excessively.
Ithe old line are " set" pretty good. I found if yo loosen the top and bottom fan bracket bolts getting the the hoses on and off is way easier.
Thanks i think I will try to find some of the fitting plugs and go from there, I appreciate the help makes it a heck of a lot easier, to know kind of what to expect
If you are just going to change the seals and clean the area up why not do the seals where the fans are mounted? If you have a 5 gallon bucket to set on you should be able to do the complete job rite there. Clean the area up with your favorite degreaser and put the blades back on. No need to unhook the hoses the inside is clean.
Mike
I agree with Mike, just pull the fans and adapter, you will need a crank damper type puller( available at HF as a kit) and a small pair of inside snap ring pliers. leave all the hoses connected. Whole lot less mess. Yours are clean compared to mine, that have been seeping for years.
Yes dont disturb if you can help it. KISS. Check to see if any lines are riding against each other. They will actually wear thru the steel braid.
Sounds a whole easier than pulling the lines they're really stiff, will just blow off the loose stuff and spray down with some gunk remover,
Thanks
Mike
My favorite for the past decade has been brake cleaner. Auto zone and buy by the case when on sale, sometimes the manager will give me a break on price by the case also
Another way is a gallon can of mineral spirits and a air powered syphon gun,cheaper then the brake cleaner and don't smell
as bad,another tip,if you need new lines they cost a little more but the braided stainless will stay flexable as opposed to the black
type.
Question is the fan hub center nut standard thread having a tough time getting it off, or does it need an impact wrench?
Thanks
Mike
The ones I have removed were standard thread and I use an impact never tried a breakover bar. No good way to hold a back up.
Mike
Make sure you use a 6 point socket with the impact,I'm assumming it's not reverse threads.
They are standard RH thread, at least mine were.
Thanks guys I looked at the threads on the pictures of the project coach from Mike, appreciate the help though,
When you do this job check the supply line going from hydraulic pump to first fan motor. Ours had a chafe where it was tied to another line that wore through and caused us a major breakdown incident. Funny story I now have a repair kit and know that I can get one of these hoses made up at any NAPA so I am a lot less worried these days about it. But it was a huge problem at the time!
I'm wondering if hydro hose fittings are available, like a weatherhead fitting ?
Other than Cat hoses with their 3x and 5x line's which have to have a machine to build those small lines on our coaches can be fixed with a WH fitting and 2 wrenches. Closest I can think of is AN fittings on fuel lines etc. screw on the outside then screw in the inner part.
Maybe I spent too much time in the field crawling around yellow iron ?
I'm sure they are. Try a marine supply store, or any hydraulic shop.
If you have a National Oil Well store nearby they can get/have fittings,they use a brand called Aeroquip,you can make the hose up yourself,have made hoses for years from 1/4 inch up to 2 inch.Anywhere there is oil and gas they have a store.
Ok anyone see this pump and seal and replaced theirs??
I had ordered the 20x30x7mm seals others have mentioned but apparently I have different motors and seals.
Mine weren't leaking horribly, I was just trying to get most of the bigger leaks taken care of. I'm reluctant now to mess with this without some guidance....inclined to put it all back together and try some power steering stop leak unless someone speaks up with advice on these pumps/seals.
Got the motor make and model.
From your picture the seal is 20-47-7. See if your have a seal shop in your area and go get the
seals from there. Take your picture into them and they will look after you. I would not put it back
together without new seals. When you put the new seals in grease the seal lip before installing the m.
Curtis,
I'm pretty sure you already saw my old post on my fan motors, but if not, linked below. Same as your motors. I'd forgotten all about my search for a seal kit way back then. If you do find a source for seals at a reasonable price, I
might get motivated enough to get greasy and tackle re-sealing our motors. Not a prospect I relish.
hydraulic fan motor (https://www.foreforums.com/index.php?topic=27326.msg223491#msg223491)
Pull one of your seals, have a bearing and seal shop
match them up, hydraulic shop may be able to help too.
Chuck,
Less than $10 bucks seems reasonable to me. The only thing better would be free or less. Here is you a link if you don't have a Motion Ind. in your area. EAI Oil Seal 20mm X 47mm X 7mm TC Double Lip w/Spring. Metal Case w/Nitrile... (https://www.amazon.com/20X47X7-EAI-Grease-Rubber-20mmX47mmX7mm/dp/B07FVCG5CH/ref=sr_1_2?dib=eyJ2IjoiMSJ9.qYKPYIiVvDlZ4P8IFnpCVwZw6q2nJHmhb6VCL3BuzrkggYmbS2vdJWZAGNHZSvRLrOpLMeg1fauBUpGnxxHacPC1tVX66mrjLXn1gle1cLZr6KFVvND8vCrRWp8q0qF0Q1yEUsctMGItzUQ9VIQbGIYGJHQimKtm-aBBn3wne1Nj8iNC0gO9aBB_9GBclXfLESxxh2RtNRSKiimaodNZdLrH4T4-HK_6dfekeWjjNpQ.m6Jvr_SZPXBkJb86O9LVokF12g2WWBp8nKpg9nyPRKg&dib_tag=se&keywords=20mm-47mm-7mm+seal&qid=1713264495&sr=8-2)
Can't help with motivation though.
Mike
Yes, I could probably scrape up that much cash. I don't remember WHY I had so much trouble finding fan motor seals when I was looking 8 years ago. As I recall, it wasn't as simple as just running down to the local hydraulics shop...we certainly have lots of those around here in the Oil Patch. Perhaps I was just as lazy then as I am now. Of course, I never actually removed my motors, so I couldn't read the seal number at that time. I was just doing a search based on the motor ID plate info.
Anyway, my motors are
still just seeping a little - not actually leaking - so not a critical problem. I'll let Curtis play around with his motors, and if he tries re-sealing them, we'll see if the seals work as expected. If they do, THEN I'll think about addressing my motivation problem. Until then, I'll just sit here in my armchair and have a nap..........
Looked up the Motion Ind.,have one nearby in Memphis.
Ok Chuck....heres another project for ya.....if we were closer I'd come help do the messy job as it seems I'm going to be pretty experienced 😳. ....and maybe a tad bit more nimble as you have a few more years of wisdom.....but I am getting pretty stiff myself.
The seals: I'll confirm fit
Shaft Oil Seals TC 20x47x7 – AVX Seals Store (https://avxseals.com/products/shaft-oil-seal-tc-20x47x7-rubber-covered-double-lip-w-garter-spring-id-20mm-od-47mm-20x47x7-20-x-47-x-7-mm)
Ok the job is done. Of note, on my '93 U280 the radiator tube does not run under the fans and there is no need to mess with the radiators or fluid. I was able to poke a hole in the old seals with a pick, tried to screw a screw in but wasn't working and I was able to just pry the seals out. A woodruff key was a bit in the way to R and R the seals, the first one I was able to pop out with effort, the second I couldn't. The taper of the shaft actually made it easy to get the seals off and on over the woodruff key, I wouldn't mess with the keys.
I had drained the reservoir by siphoning, it drains slowly and I pulled a few lines at the fans off and let it drain a day before getting to work on the messy job removing the fans. .....if you like your clean concrete driveway I'd suggest doing this job in your neighbor's driveway when they're gone on vacation. 👍👍👍😜
I was a bit concerned about whether the system would refill its lines, motor and fans without cavitation when I was done. It took about a minute or two of running then the fans started turning. All seems good so far.
This was happening before this job but my fan system seems to have a surging when idling ....sort of a whoooup, whoooup, every five or ten seconds, not always but often, seems to go away off idle....any thoughts?
'Hoping it's not any issue to worry about with the motor.
Curtis
Curtis,
I think I recognize the weird surging "thing" you're talking about when your engine is idling. Our coach also does that, not on every start but sometimes. Usually happens after a cold start, when it has been sitting for a longish period of time. It always goes away as soon as I raise the idle up a little (with the cruise control). It has never been associated any other recognizable problem. I have no idea what causes it - and since it seems to be harmless I have never worried about it.
Congrats on getting the seals installed. After you've put a couple hundred miles on them, try to remember to come back and tell us if they are still holding up well.
Cheers
The sound sounds like surging in the hydraulic fan system. I'll keep an eye one it. ...and check to see if fan speed surges with the sound.
Planning a trip in a couple weeks. I'll let y'all know if my leaks are solved , fingers crossed...all good so far just running it in the driveway so far.
As Bruce said in post 65 best bet is to pull a seal--from what I am seeing on these post there is more than one size for the fan motors when I replaced my seals they were 20 ID x 30 OD X 7 thick-- I got my seals off Ebay they were CR brand(Chicago Rawhide)
I think I paid 10.00 for 5 seals--currently they are 9.00 each
Chris