Out mowing with the AC 160 (leaky seal?)
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Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=172074
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Topic: Out mowing with the AC 160 (leaky seal?)
Posted By: garden_guy
Subject: Out mowing with the AC 160 (leaky seal?)
Date Posted: 16 Jun 2020 at 12:20pm
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Got the AC 160 mower out yesterday now that the ditch is somewhat drier here in IL. But man, I am getting a lot of oil leaking onto the deck from the gearbox... Any idea if I can replace the seals on this thing or what to do (or is corn head grease the way to go)?   It does a good job cutting -- but still ran into some mud!   Spent a good... hour out there down in the valley. Hit a log the size of my leg that had fallen in the winter; thankfully the rattle clutch still works good. Will have to get down there with the other tractor and chainsaw and move a few more downed trees.
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Replies:
Posted By: TimNearFortWorth
Date Posted: 16 Jun 2020 at 1:16pm
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That front is known to leak as they get older and I changed mine a few years ago, any bearing seal house should be able to set you up and I ran 80/90 along with good grease for a couple years before changing my front seal. Front cover and driveline may look daunting but it comes apart quickly, just watch that no parts go flying when you remove the ratchet assy. portion and leave the large tension nut where it is currently if it's been operating ok. Bottom seal on mine has never leaked and good to give that lower seal a shot of grease, seem to recall zirk fitting is at base towards rear.
FYI, good to check the breather fitting can breathe freely on that gear box as they will push oil out the front seal if plugged off. Mine was when I bought it and leak slowed at front seal after cleaning the vent fitting. Nice mower, mine is the 3-pt. version and one tough old gal.
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Posted By: garden_guy
Date Posted: 16 Jun 2020 at 3:36pm
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Yeah I'll take some better pics of the leaks next time I am out. Does the housing just unbolt to get to the seals? Fantastic mower. Does an amazing job, even with the blade being trashed on it for years now. Plenty of mower for the WD! Also.... There's a vent/breather on this thing? Where would I look for that?
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Posted By: Tracy Martin TN
Date Posted: 16 Jun 2020 at 3:53pm
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You will never get it to stop leaking. The seal runs on the od of the splined drive line. The part that drives the gearbox from PTO.Got mine apart right now. The oil will seep between the splined shaft and the internal splined drive of over running clutch. HTH Tracy ------------- No greater gift than healthy grandkids! |
Posted By: garden_guy
Date Posted: 16 Jun 2020 at 4:43pm
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Is the reason for that just due to excessive wear inside after all this time? I don't remember it leaking this bad 15 years ago, and I'm good about keeping the oil fresh and filled. |
Posted By: Alvin M
Date Posted: 16 Jun 2020 at 4:46pm
| There Should Be a O Ring Between The Over Running Jaw And The Brg |
Posted By: DiyDave
Date Posted: 16 Jun 2020 at 5:17pm
Also, make sure that the breather plug, on one side of the gearbox, is still breathing. If not, oil heats up, pressurizes, and leaks past seal... ------------- Source: Babylon Bee. Sponsored by BRAWNDO, its got what you need! |
Posted By: garden_guy
Date Posted: 16 Jun 2020 at 9:12pm
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Hmmm seems like I have just "plugs" on both the "fill hole" (that is basically a 90 degree pipe elbow that faces up?), and the side hole which I have always assumed is the "level plug", for how I've always filled it. Don't see a vent in either, unless I am missing something. |
Posted By: DiyDave
Date Posted: 17 Jun 2020 at 4:53am
Plug in the elbow should have a vent in it. Best ones have a sintered bronze insert, that lets air in, but not dirt. I've seen home made ones, where a hole is drilled upward, from the bottom of the plug, then another hole is drilled on the side of the plug, to meet the other hole. Here's a link: https://www.surpluscenter.com/Brands/Prince-Mfg/3-8-NPT-Bronze-Breather-9-4195-6.axd" rel="nofollow - https://www.surpluscenter.com/Brands/Prince-Mfg/3-8-NPT-Bronze-Breather-9-4195-6.axd ------------- Source: Babylon Bee. Sponsored by BRAWNDO, its got what you need! |
Posted By: garden_guy
Date Posted: 17 Jun 2020 at 2:14pm
Thank you for this! I am going to order one and see if this helps me out.
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DiyDave wrote:Posted By: DiyDave
Date Posted: 17 Jun 2020 at 5:11pm
Check the size, on your plug, before ordering, the link was an example, only...  ------------- Source: Babylon Bee. Sponsored by BRAWNDO, its got what you need! |
Posted By: garden_guy
Date Posted: 17 Jun 2020 at 10:04pm
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No worries -- that's my plan, haha! ;) |
Posted By: Dave (NE)
Date Posted: 18 Jun 2020 at 2:35pm
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I never knew that was supposed to be a breather plug in the 90 degree elbow pipe fitting. Did you figure out what size it is? I should get one of those bronze breathers too. This has been an informative learning post. I checked, and my 5 foot snap coupler shredder appears to have some sort of breather plug on it which I think I should replace with the bronze type as shown in the surplus center site. Dave ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: Dave (NE)
Date Posted: 18 Jun 2020 at 3:23pm
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Found that zirk Tim mentioned. Had never put any grease in there before. Hope I am preventing a problem. ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 18 Jun 2020 at 11:42pm
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Something had to have gotten plugged up somewhere, I just need to figure out where. There must have used to be a breather hole that is now plugged? Check the oil on my deck:  |
Posted By: Dave (NE)
Date Posted: 19 Jun 2020 at 8:41am
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I looked at the plug on the 90 degree elbow on mine and it sure looks factory without any breather. Don't see where there would have been a breather on the gear box when it came out from the factory. ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 21 Jun 2020 at 11:12am
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Going to take some pictures today to post later. Measured the plug and it sure does seem like 3/8 NPT, at least. |
Posted By: DiyDave
Date Posted: 21 Jun 2020 at 4:54pm
I may have been mistaken on the location, and My memory aint the best, it could have the breather on the top, too... ------------- Source: Babylon Bee. Sponsored by BRAWNDO, its got what you need! |
Posted By: Dave (NE)
Date Posted: 21 Jun 2020 at 5:15pm
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On the top? I'll have to go out and check again before going and just buying a breather plug, I guess. ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 21 Jun 2020 at 11:15pm
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Here's some photos, if anyone wants to point out where they think a breather may already be... Starting with the "filler" plug side:  Top shot:  Bottom shot:  Drain plug side:  And lastly, one of the rear:  |
Posted By: garden_guy
Date Posted: 23 Jun 2020 at 3:13pm
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I went ahead and ordered the 3/8 NPT breather plug, and figure I may as well fill her up and try it. Unless another breather port seems apparent that is plugged or that I missed? |
Posted By: DiyDave
Date Posted: 23 Jun 2020 at 5:22pm
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I did notice one more thing... That grease fitting is on the top, on yours, on mine, its on the bottom. I suspect someone has rotated that rear flange 180º... ------------- Source: Babylon Bee. Sponsored by BRAWNDO, its got what you need! |
Posted By: Dave (NE)
Date Posted: 23 Jun 2020 at 7:36pm
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It, the grease fitting, is on the bottom on mine. ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 24 Jun 2020 at 10:41pm
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So I think the little circle above the center in the back of the gearbox is the "breather" vent, but I could not get it to pop for me at all. I soaked it down with PB Blaster tonight. Will check it again this weekend, and if nothing else, will soak it again. Maybe it rusted up? |
Posted By: Dave (NE)
Date Posted: 25 Jun 2020 at 8:58am
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not sure about that. Isn't that about the height of the fill to plug on the side? seems like the breather plug should be higher than that. I will look again, too, at mine. ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: Tracy Martin TN
Date Posted: 25 Jun 2020 at 9:42am
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The relief fitting as manual calls it is part # 916619. It is in center of top two bolts holes in pics in my manual.Grease fitting for cutter shaft is at bottom. HTH Tracy ------------- No greater gift than healthy grandkids! |
Posted By: Dave (NE)
Date Posted: 25 Jun 2020 at 10:21am
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oh, I saw that there but didn't realize it was supposed to be a breather plug, as it is pretty much all rusted over on mine. ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 25 Jun 2020 at 12:06pm
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I forgot to double check my manual. I'll do that this weekend when I get back over to the tractors. Assuming it's a standard thread and pressure setting? Or else I can just put a breather in the filler neck to the same effect? |
Posted By: Dave (NE)
Date Posted: 25 Jun 2020 at 3:57pm
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Well, it wasn't rusted over but just had grease on it. Yes, it is some sort of breather, so makes sense where it is located. Also looked on my 5' snap coupler shredder and found a breather now that I know more of what I'm looking for. So, the consensus is that these breather plugs should be replaced by the bronze breather plugs from surplus center? ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 27 Jun 2020 at 11:30am
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Hmmm I see places like Fastenal sell a 1/8" NPT dynaflow "relief fitting"... It looks a lot like the thing that is already in there. Anybody know if 1-5 PSI would be about correct? Tempted to see if I can swap the one already in there... Or if anyone else has put a breather in the filler port.
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Posted By: SteveM C/IL
Date Posted: 27 Jun 2020 at 12:29pm
| I can't tell from pic but isn't that one of those spring loaded reliefs that look like a grease zerk at first glance. |
Posted By: garden_guy
Date Posted: 27 Jun 2020 at 1:19pm
Looks like this similar part from Fastenal to me. Maybe I'll just see if I can find a drop in replacement. 
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Posted By: Dave (NE)
Date Posted: 27 Jun 2020 at 4:17pm
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I plan on stopping by Surplus Center on Monday to see if they have the breathers that will fit the breather hole and how much they are. I need a couple of them. I'll let you know what I find out and how much they are. Dave ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: DiyDave
Date Posted: 27 Jun 2020 at 5:58pm
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The whole reason I posted it, was that its cheap, and has no moving parts, to fail. Only here can we debate the virtues of a part, that costs less than $5... ------------- Source: Babylon Bee. Sponsored by BRAWNDO, its got what you need! |
Posted By: garden_guy
Date Posted: 29 Jun 2020 at 12:56am
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Well it sure seems like a good upgrade to me. Works better than the "plugged vent" I've got going now, haha. Any idea how many PSI the original relief vent was supposed to be? I see replacements in the 0.25 to 1.0 PSI range, or the 1 to 5 PSI range, or even higher.
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Posted By: DiyDave
Date Posted: 29 Jun 2020 at 4:28am
It can't be much pressure. Brings to mind another thought. Have you got a IR thermometer? If so, see what the temperature that gearbox is running, when its hot. Much over 250ºF, and your oil is close to burnin... ------------- Source: Babylon Bee. Sponsored by BRAWNDO, its got what you need! |
Posted By: Dave (NE)
Date Posted: 29 Jun 2020 at 1:34pm
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Well, it takes a 1/8" breather plug for both my 172 spreader and my 5' snap coupler spreader. Surplus Center does not carry these. Plus, they only have curb side pick up due to the virus, so I wasn't able to go in and compare with what they had to readily determine the proper size. Ended up keeping the couple 1/4" plugs I purchased to compare with what I had. Went to Central States Hydraulic Services in Lincoln and picked up a couple of the 1/8" breather plugs and just got them installed. $2.88 each. Invoice says max press 150 psi and max temp 300F. All ready to go now, I guess. ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 02 Jul 2020 at 7:41pm
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Been spraying this with PB Blaster for off and on for a few weeks now. Came right out today, and man it was plugged up good. Nothing I tried would touch the gunk in here; I'd say its toast. I ordered a new one of the 1-5 PSI range from ebay.   Tried at Fastenal but the guy looked at me like I was crazy when I showed him the part I was looking for, haha. |
Posted By: Tracy Martin TN
Date Posted: 02 Jul 2020 at 9:26pm
------------- No greater gift than healthy grandkids! |
Posted By: garden_guy
Date Posted: 02 Jul 2020 at 10:04pm
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Got a pair of 1-5 PSI replacement plugs on my way from ebay. They appear to be 1/8" NPT. |
Posted By: Dave (NE)
Date Posted: 03 Jul 2020 at 10:40am
Here is a picture of the breather plug I installed. It is the screen type plug as discussed above. Also, are some pictures of the plugs I removed. The one on the left is from my 172 spreader. On the right, from my snap coupler spreader. Hope this works.    ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 03 Jul 2020 at 5:23pm
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Looks nice Dave! I got that kind of breather plug that will fit in the filler neck. I've got an original style "grease zerk" looking plug coming from ebay this week. Really hoping this solves the issue -- let me know how yours works for you!! |
Posted By: Dave (NE)
Date Posted: 03 Jul 2020 at 5:43pm
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Well, I was fortunate and didn't have problems to start with, so hope this new plug will prevent any possible future problems. Very interesting to find out all of this information about breather plugs and the need for them. Did not even have any knowledge of them until I had issues with the single action cylinder on my shredder. Got it rebuilt with one of those plugs installed and it has worked fine. Can anyone explain the PSI needs/requirements? As I mentioned, mine said 150 psi. You state 1-5 psi. What's the deal? ------------- Do not argue with an idiot. He will drag you down to his level and beat you with experience. Mark Twain. |
Posted By: garden_guy
Date Posted: 03 Jul 2020 at 7:49pm
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Dave, I could find zero information on what I was looking for. Whereas those breather plugs operate both directions all the time, I believe the ones I bought in the "1-5 PSI range" means that they have a 1-5 PSI cracking pressure before they open, which I feel is pretty low. Fingers crossed that fixes it for me, but if not, I have a breather like you have to put in the other plug spot. |