User Tag List

Page 1 of 5 1 2 3 4 5 LastLast
Results 1 to 15 of 61
  1. #1
    Join Date
    Aug 2017
    Location
    Grand Cayman
    Posts
    301
    Thanks (Given)
    175
    Thanks (Received)
    17
    Likes (Given)
    206
    Likes (Received)
    144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Lower Unit Oil Leak: Fix with Epoxy?

    After taking my modded XR6 gearcase out of storage yesterday to install it on my boat, I realized that it was leaking oil, and there was a bubble on the side where the oil was leaking from. I bought this gearcase back in October of last year from a S&F member as a freshly built unit (billet carrier/ cut down SM gears, etc.), and I noticed when I got it that it had a small bubble on the side, with a small trace of gear oil, which I assumed might have been from a very slight leak where the original oil drainplug was (I actually have no idea where that would be), and the leak was caused by the drop in air pressure in the cargo hood when it was air-frighted to me.
    I contacted the vendor and was assured that the unit was solidly built and sound, so I put it in storage until I was ready to use it.
    Now, yesterday when I took it out to cut a slot for the shifter linkage and to fit the 12Ē adaptor plate on it, I noticed oil on the side of it and saw that the bubble was much bigger, so itís obviously been leaking just sitting in the box.
    I used a screwdriver and ripped the epoxy bubble open and it was saturated with gear oil (you could smell it too) and I scraped it down to the aluminum underneath (it came off easily), but I canít see any leak, so it must be small.
    Iím thinking of putting some low air pressure inside the case through the air vent and see where that pushes oil out, to figure out where the leak is.

    So, hereís my question:
    If there is a small pin-hole or crack in the case (it has some pretty deep gouges in the aluminum from a grinder), can I repair that with a good epoxy? If so, what works best, in terms of strength and being impervious to oil seepage?
    Or do I need to get it welded? If so, can I take the chance to have it professionally welded while itís still together?
    Canít believe Iím having to do this sh!t after what I spent on this unit.

  2. #2
    Join Date
    Feb 2009
    Location
    Edgewater,B.C. CANADA
    Posts
    8,122
    Thanks (Given)
    152
    Thanks (Received)
    293
    Likes (Given)
    3226
    Likes (Received)
    1152
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The hard part will be getting the area totally oil free for epoxy to stick or even weld to stick. Would try epoxy first, grey Marine Tex or Belzona would be first choices on epoxy.

    Dave
    1980 Cougar 19 tunnel,90 2.4L Bridgeport EFI in middle of restoration.
    1988 BAJA Sunsport 186, 96 225 Pro Max
    79 12' Auminum, 95 Merc 9.9
    RIP Stu
    "So many idiots, so few bullets"

  3. Thanks CI STV, phillnjack thanked for this post
    Likes phillnjack, specboatops liked this post
  4. #3
    Join Date
    Aug 2017
    Location
    Grand Cayman
    Posts
    301
    Thanks (Given)
    175
    Thanks (Received)
    17
    Likes (Given)
    206
    Likes (Received)
    144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thanks. I’ll drain the oil and would clean everything good with acetone to make sure there’s no oil residue.

  5. #4
    Join Date
    Feb 2011
    Location
    HUDSON, FLORIDA
    Posts
    1,132
    Thanks (Given)
    304
    Thanks (Received)
    47
    Likes (Given)
    361
    Likes (Received)
    300
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dave Strong View Post
    The hard part will be getting the area totally oil free for epoxy to stick or even weld to stick. Would try epoxy first, grey Marine Tex or Belzona would be first choices on epoxy.

    Dave
    JB WELD i works good has never failed me. fixed a large case hole,worked great.

  6. Thanks CI STV, phillnjack thanked for this post
    Likes phillnjack liked this post
  7. #5
    Join Date
    Aug 2017
    Location
    Grand Cayman
    Posts
    301
    Thanks (Given)
    175
    Thanks (Received)
    17
    Likes (Given)
    206
    Likes (Received)
    144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by KIRCHNER View Post
    JB WELD i works good has never failed me. fixed a large case hole,worked great.
    I actually already have some of that in my garage. Have always had good results with that too.

  8. Likes phillnjack liked this post
  9. #6
    Join Date
    Aug 2017
    Location
    Grand Cayman
    Posts
    301
    Thanks (Given)
    175
    Thanks (Received)
    17
    Likes (Given)
    206
    Likes (Received)
    144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Here’s what my fancy $3800+ XR6 L/U looks like under the three layers of filler, not sure whether it’s all epoxy, and/or Bondo and fiber-strand/filler… The green chunk is the bubble that lifted off.
    Click image for larger version. 

Name:	7E984B1F-1213-453C-9CA6-08ACE5E9BC3F.jpg 
Views:	203 
Size:	414.3 KB 
ID:	491320


    Note the puddle of oil that seeped out overnight.

    Click image for larger version. 

Name:	156833F0-01E2-44BA-BFFA-3E6F29637939.jpg 
Views:	201 
Size:	400.0 KB 
ID:	491322


    I pressurized it with low air pressure and sure enough oil started to leak out. It’s leaking in two spots where it was welded to fill in the original water pickups. One looks like a hairline crack in the welding, and the other is a bubble or pinhole in the weld. The crack leaks a pretty significant amount of oil when you put just a little air pressure in it, so that’s the main problem. It’s pretty visible when you look at it up close too.

    Here’s a close-up, with the two problem areas circled:

    Click image for larger version. 

Name:	FF2987E4-3D6B-4AEE-9DF7-C3A1BF154F90.jpg 
Views:	200 
Size:	421.6 KB 
ID:	491321
    Last edited by CI STV; 08-03-2021 at 08:17 AM.

  10. #7
    Join Date
    Aug 2017
    Location
    Grand Cayman
    Posts
    301
    Thanks (Given)
    175
    Thanks (Received)
    17
    Likes (Given)
    206
    Likes (Received)
    144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I bought a big pack of JB Weld today. I’m hoping that it will hold and not allow any oil seepage.

  11. #8
    Join Date
    Jan 2004
    Location
    Florida
    Posts
    30,476
    Thanks (Given)
    35
    Thanks (Received)
    1225
    Likes (Given)
    196
    Likes (Received)
    13423
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    ...time for a new housing...

  12. Likes Capt.Insane-o, phillnjack liked this post
  13. #9
    Join Date
    Jun 2009
    Location
    Bristol, Connecticut
    Posts
    716
    Thanks (Given)
    74
    Thanks (Received)
    15
    Likes (Given)
    62
    Likes (Received)
    113
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    3800 for a coned xr lower unit??
    The epoxy might be enough to stop the leak
    Probably cracked from having water freeze in the pickup cavity
    Should fill that cavity with epoxy also

  14. Likes phillnjack liked this post
  15. #10
    Join Date
    Aug 2017
    Location
    Grand Cayman
    Posts
    301
    Thanks (Given)
    175
    Thanks (Received)
    17
    Likes (Given)
    206
    Likes (Received)
    144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FUJIMO View Post
    ...time for a new housing...
    Really? Sh!t! I haven’t even run this one yet. The guy I bought it from says he does them all the time for a bunch of big name racers, and that this one was was freshly built and never run. I guess that means it wasn’t tested too. There’s no such thing as a new housing with these things anyhow, is there?

  16. #11
    Join Date
    Aug 2017
    Location
    Grand Cayman
    Posts
    301
    Thanks (Given)
    175
    Thanks (Received)
    17
    Likes (Given)
    206
    Likes (Received)
    144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Aaronhl View Post
    3800 for a coned xr lower unit??
    The epoxy might be enough to stop the leak
    Probably cracked from having water freeze in the pickup cavity
    Should fill that cavity with epoxy also
    Yep, it has a billet carrier and cut down SM gears, supposedly. It actually cost me $4250 with overseas air freight and then 27% import tax, so I have like $5,400 invested in it. So, yeah, I’m p!ssed about this.
    I’m not sure what cracked it, but there’s no way it should be leaking oil, since it was professionally built. The cavity appears to be welded up and the two leaks are in the welded area. I have no choice to try to epoxy it and hope that it holds.

  17. #12
    Join Date
    May 2016
    Location
    keys
    Posts
    813
    Thanks (Given)
    31
    Thanks (Received)
    42
    Likes (Given)
    254
    Likes (Received)
    415
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Can I assume that case will be run in saltwater? Grand Cayman can't have fresh water big enough to run fast boats in?

    A bondo conned case in saltwater will be a never ending maintenance job. It will just keep bubbling and peeling and popping chunks. Epoxy will last a little longer but water will still eventually get behind it and pop chunks loose.

    I don't think you'll have much luck trying to seal those leaks with any type of epoxy, jb, marine text,. I might still try though if I couldn't get access to a competent welder.
    Give them a slight v grind and put the case under a slight vacume to help draw the epoxy into the crack, after you clean, clean, clean, then clean again.

    Down side is if this doesn't work it will make it a much bigger nightmare to weld later on.
    ANTI40​It's just an idea.

  18. Thanks CI STV thanked for this post
    Likes JR IN JAX liked this post
  19. #13
    Join Date
    Jun 2018
    Location
    Floating around
    Posts
    2,672
    Thanks (Given)
    252
    Thanks (Received)
    234
    Likes (Given)
    1676
    Likes (Received)
    1390
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    There are products that will seal that leak. Seals all comes to mind and I’m sure there are others. It’s not any kind of epoxy nor does it have strength but it will stop the leaks.

    if it were mine I’d find someone with a spool gun and start laying in tacks and pressure test til it was leak free. Grind as little as possible to allow for fairing. Pressure test again to ensure it’s still leak free and then use epoxy over it. I haven’t had a lot of luck with regular jb weld when submersed. The marine jb weld works well but it’s approx 1/3 the strength or marine Tex which is excellent product in my brief experience with it. Holds strong and fully water proof.

    if the welder option is off the table if so some testing on scrap aluminum with seals all and epoxy over it and test for bonding. This way you get the leak sealed and hopefully the epoxy over it for strength.


    I have no skin in this game so I cannot comment on the build quality but those imperfections would be easy to miss during fabrication. Maybe a pressure test would have indicated these leaks but only if there was lube in it. It’s doubtful that a dry pressure test would have revealed that leak.

    I used this on a damaged transfer case on my plow truck that was leaking a steady drip. I smeared it on and filled it because snow doesn’t wait for repairs. It’s been three years and it’s still not leaking

    Click image for larger version. 

Name:	DBD9BF5B-E459-456A-9765-AC13C6645C67.jpeg 
Views:	16 
Size:	169.4 KB 
ID:	491329
    Hydrostream dreamin

  20. Thanks CI STV thanked for this post
  21. #14
    Join Date
    Aug 2017
    Location
    Grand Cayman
    Posts
    301
    Thanks (Given)
    175
    Thanks (Received)
    17
    Likes (Given)
    206
    Likes (Received)
    144
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Many thanks, folks.
    Yes, it is going in saltwater, although only for short periods, since itís a single seat race boat that Iím setting up for drag racing.
    That Seal-All stuff is something I looked at yesterday when I picked up the JB Weld. Good to know it works.
    Iím going to see if I can find a competent welder around here, but my worry is that when they try to ďfixĒ it, they f@ck it up worse than it is. Thereís a guy around here that welds leaky radiators and I got him to patch a hydraulic oil cooler on an excavator before and that worked. If that doesnít work, Iíll try the epoxy.
    I know these flaws may have been hard to spot with the naked eye, but when youíre selling parts to racers, and youíre welding on an aluminum case that obviously needs to be leak-proof, I would expect at least a vacuum or pressure test after itís assembled.
    I already have an old JC coned XR6 that was built in the 90s that doesnít leak, and I stupidly opted to buy this unit because it was advertised here on S&F as a newly built unit, rather than rebuilding the old one.

  22. #15
    Join Date
    Jan 2003
    Location
    aalsmeer
    Posts
    1,025
    Thanks (Given)
    0
    Thanks (Received)
    64
    Likes (Given)
    4
    Likes (Received)
    77
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Hard to see how thick that bondo is but maybe weld an aluminium plate over it?
    Because they might have gone overboard with the grinder with multiple thin spots!
    I thought the cayman islands where suppose to be a tax evasion paradise!?

  23. Thanks CI STV thanked for this post
Page 1 of 5 1 2 3 4 5 LastLast

Similar Threads

  1. Epoxy for Lower unit
    By banchee6 in forum General Boating Discussion
    Replies: 3
    Last Post: 06-16-2017, 09:48 PM
  2. Epoxy that closely matches aluminum lower unit color
    By Mr. Demeanor in forum Technical Discussion
    Replies: 12
    Last Post: 08-10-2014, 05:20 PM
  3. Another epoxy-filler lower unit-question...
    By Hydro-T20 in forum Fiberglass and Composites Discussion
    Replies: 4
    Last Post: 07-29-2007, 02:38 PM
  4. Lower unit leak
    By 300Procraft in forum Technical Discussion
    Replies: 9
    Last Post: 05-17-2005, 10:38 AM
  5. Lower Unit Epoxy Filler
    By C/E in forum Technical Discussion
    Replies: 15
    Last Post: 06-22-2004, 08:52 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Aeromarine Research