My Tractor Forum banner

1 - 20 of 21 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter #1
I need some advice from the Lawn Boy veterans; I've searched the forum to no avail. The lower oil seal on my Lawn Boy model 10515 won't stay in. I have installed a new seal three times (cleaning the crankcase and seating it with a length of prepped pvc pipe), but each time the seal promptly drops out while mowing. The last time I double-checked the crankcase bolts (they were very tight) and used a thin layer of Permatex gasket sealer, but no go. The mower still runs surprising well, perhaps because the seal only drops to the top of the self-propelled drive pulley?

Does someone make a slightly oversized oil seal for a tight fit? Do you think it would work to set a second seal on top of the drive pulley to keep the first seal in the crankcase (so it can't drop completely out)? Anyone else have this problem? Suggestions/solutions?

Thanks!
 

·
Premium Member
Joined
·
1,301 Posts
Use some loctite when putting it in and let it sit until dry


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
11 Posts
Discussion Starter #3
Thanks, ReedZ! Do you use loctite threadlocker, or is there a type to use where it isn't a threaded fitting?
 

·
Registered
Joined
·
2,345 Posts
I would just use the blue loctite. make sure its completely clean and oil free. Use some brake parts cleaner. Like Reedz said make sure its good and dry before you flip it over and let some oily gas drip out.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #5
Thanks - I actually just walked next door to a John Deere dealer - they recommended using Loctite gasket maker 515 - purple stuff. I also have the blue threadlocker...let's see what works. Thanks for the advice! Have a great weekend!
 

·
Registered
Joined
·
11 Posts
Discussion Starter #6
F-Series - I'm using the rubberized one (looks just like the 2nd picture you posted). I verified the part with my local Lawn Boy service place...it wasn't completely loose, but went in w/o much pressure.
 

·
4K Poster!!!!
Joined
·
4,798 Posts
I agree that loctite should be used in this case, even though the books don't mention it. From my experience either seal, metal rimmed or the OEM rubber coated seal will benefit from a bead of thread locker around the lower perimeter of the crank bore. That ridge that will be formed with the thread locker will make it much harder for the seal to migrate down and out of the bore, I've heard a lot of folks say it's rubbish, that it won't stick to the rubber, well I can tell you from experience of removing quite a few seals that it takes a much greater effort to get those seals out where loctite was used, which is exactly what you want. It's really not mandatory for the loctite to adhere to the seal, it just needs to adhere to the inside bore of the crankcase, that strong ridge that is formed will do the job, and that is exactly why the brakes parts cleaner, or similar non-residue solvent, should be used to prep the crank bore surface for adhesion. Another thing to consider is to lower the pressures within the crankcase by making sure the engine is breathing well with the least amount of exhaust restrictions. It's Bernoilli's principle, pressure is directly proportional to the restriction to flow, and that is true no matter what is being moved, fuel/air mix, hydro fluid, gas, etc. etc. A pump doesn't create pressure, it's the restriction to flow that creates the pressure.
 

·
Registered
Joined
·
428 Posts
611396 was the seal used on the 10515. These seals have been known to fall out. Seal 609342 (C/R 8624) is a better choice.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #9
Wow, that's an interesting thought! My yard is sloped, so I do use the self-propelled feature most of the time. That would put some sideways pressure when it pulls on the crankshaft...I just hope that doesn't mean there's no solution!
 

·
Registered
Joined
·
11 Posts
Discussion Starter #10
Thanks for the feedback! Would you apply the loctite after seating the seal in order to form the ridge, or apply to the seal, or the crankcase. When I tried the permatex, I only applied to the seal so as not to push any into the crankcase. Is the other seal number given a larger OD seal? I will have to double check the PN of the ones I bought. Thanks!
 

·
Moderator
Joined
·
5,262 Posts
Hey Mike72! Care to offer some additional information on that optional seal? According to ereplacementparts.com that part number was only used on about 9 machines. What's the inside scoop? Bill
 

·
4K Poster!!!!
Joined
·
4,798 Posts
Thanks for the feedback! Would you apply the loctite after seating the seal in order to form the ridge, or apply to the seal, or the crankcase.
What I do is apply the loctite to the seal prior to installation and then after it's driven in I put a bead around the outside perimeter, wipe off the extra, but leave a ridge around the outside perimeter.
 

·
Registered
Joined
·
428 Posts
Copied from earlier posts:


Echoman, I don't want to bore you with too much detail,though there is a story behind the 605020 seal. Let me just say that in later years there were some bad runs of product (undersize OD) and at least 2-3 different manufacturers. Look for the green ones from C\R. The coating (bore tite) is made to activate when the seal is pressed into the bore. A good seal should measure 1.253-1.255 for a good press fit assuming the bore you are pressing into in not worn.


From my experience the LB 609342 (C/R 8624) with green bore-tite coating fits tighter than the 611396 and will not drop out. The seal dropping problem started when Lawn Boy switched to the 611396 seal.
 

·
Registered
Joined
·
45 Posts
Hi guys, for me this in an interesting and timely topic. Yesterday I took my well worn, 2004 model 10323 apart, removed the old lower seal and stopped for the evening. This is my first seal replacement in a Duraforce, and last week I went to the local hardware store that has lots of old Lawn Boy parts and picked up a new seal. Both my old and new seals are the rubberized type and have on top of the seal: TTO D714 2 TC 25 47 6. Not sure if these are the "good" seals, but I'm probably going with it since I already have the new seal.

I've not used Loctite on seals before, but I do have a large tube of Permatex brand, medium strength Blue threadlocker GEL. Does anyone know if the Blue, medium strength threadlocker GEL from Permatex will work as well as Loctite blue liquid on the outside of the seal?

Thanks,

Joe H.
 

·
Moderator
Joined
·
5,262 Posts
Not an expert on Duraforce but from what I know we are talking two different types of installation. The F series and older get the seals driven in but the Duraforce engine case has to be split to install the seals. Should be no need for any sealant on a Duraforce since the seal sits in a groove, hence the reason it is not driven in. If this info is incorrect please feel free to post the correct info. Bill
 

·
Registered
Joined
·
45 Posts
Hi Bill, my Duraforce's lower seal was secured with a lock ring. And after I took out the lock ring, the seal came out fairly easily by puncturing the seal with a small screwdriver and lifting/prying the seal out.

On my 2004 Duraforce, I don't see any grooves where the seal seats. Instead, the area where the seal goes is machined nicely smooth and circular. And I read online where other guys have "pressed in" the lower seals with PVC pipe, but I'm not sure if they were working on Duraforces or not. Anyway, I just got back from a local store that had schedule 40, 1 1/4" inside diameter pipe, and that pipe comes close enough to the outer edge of the seal that I'm going to give it a try.

I'll let you know if it works,

Joe
 

·
Registered
Joined
·
45 Posts
Oops, please excuse my lack of LB knowledge, but I just figured out that a 10515 is an F series. Dang, thought that it was a Duraforce like my 10323 and 10550.

And Bill, the seal was pretty easy to install using the piece of PVC pipe. I did use Loctite Blue242 on the outside edge of the seal, so I've got the engine sitting upside down until tomorrow, to let the Loctite cure.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #18
As an update: I cleaned where the oil seal sits with brake cleaner (was doing a brake job on my wife's car at the same time!) and cleaned it well. I applied some permatex gasket maker (instead of the sealant I used previously) to the seal and a bead of loctite blue thread locker to the top of the seal after pressing it in. Left upside down for abt 20 hours. The good news is that I mowed abt half of my lawn & the seal is still in place!

Thanks for the advice. Hopefully it will hold, otherwise, I'll have to try something else!
 

·
Registered
Joined
·
45 Posts
Hey Love my LB, that's great. Hope that your mower is fixed. On my 10323 lower crankcase seal job, I did a similar cleaning with brake parts spray cleaner and used Loctite blue on the outside edge of the seal. And even though my engine is a Duraforce, I pressed in the seal using a piece of PVC pipe. And like you, I left the motor upside down for over 20 hours. Put the mower back together around lunch time today, and my high mileage 10323 is back in service and running very well. While my motor was upside down on the workbench, I observed some side play in the crankshaft. Anyway, all is well so far, and I mowed three yards this afternoon with my Lawn Boy.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #20
That's great - sounds like it works. I will know better w/in this week when I mow the full lawn - sure hope it's "the fix." Btw, I did a quick web search for seal 609342 - seems like most refer to 611396 as the replacement for that part number. Hope I won't need it.

Thanks for all the suggestions - have a great week!
 
1 - 20 of 21 Posts
Top