Old Hanna came to me with a crack in the differential that had been welded. I have attached pics for reference. The problem is that the crack still leaks gear oil. Over the winter it would lose about a pint a week (into a bucket I stuck under the crack). Mobile Maintenance is a local outfit that services heavy equipment, including sophisticated welding. I will be speaking with them on Monday or Tuesday, but wonder if there is wisdom in the community about this. Perhaps questions that I should put to Mobile Maintenance? Of course the ideal would be to replace the differential housing. But that is well beyond my budget... Grateful for the wisdom in this community!
I'll just put this out there to see if anyone shoots holes in it. If the weld/structure is sound, what about some sort of epoxy repair to seal it up? I say the structure us sound part, because another weld attempt might open up a can of worms.
Thanks, skyking1. I have been wondering the same thing. The structure is appears sound. There is no visible crack or evidence of structural integrity being compromised. It simply leaks. Have others had success with such issues using epoxy? And, if so, what did you use?
I have not tried, but I would prep same as for a weld, do a little grinding to prep, then drain it out clean it with brakleen or similar several times.
After purchasing my 666 Ranger log skidder, I noticed it had a crack in the bottom of the transmission that was welded but leaking. I drained the tranny, cleaned it up and put JB weld on it as it was a bugger to get to it thru the inspection holes in the frame. I put a heat lamp on the JB weld overnight to keep it warm and help it cure. Now, 15 years or more later, it is still dry. If it is holding structurally I would not be concerned with a good epoxy product like JB Weld.
I agree. If the existing weld is structurally OK then don't mess with it. I've had very good luck using Loctite 290 to seal up porous castings. Getting all the oil out is the key. Brake cleaner and/or heat to burn out the oil.
Oh’ No!! Poor Hanna! Looks like the inside weld already has JB Weld on it. Am I seeing that right? This is my $.02 cents. Start with the least invasive option, first. Wire brush the old JB weld off the best you can. Clean with brake cleaner and follow up with some heat and alcohol. ( not for you, onfoot, for Hanna). Get this stuff and coat the welded area on the inside. It’s like epoxy, but more better. Amazing stuff. It’s used at the Cat factory to fix casting pinhole flaws. It’s used to repair cavitation damage on engine blocks. Amazing stuff. Cat 1U-6142: BELZONA Kit
Like that idea Coaldust. Thanks for sharing.
Belzona is the king of epoxies. great stuff.
Thanks, guys. Checking with Cat this morning and they no longer supply the Belzona kit. Checking out Belzona directly, their website has a range of products. Will connect with their Canadian supplier tomorrow to see if they can tell me what went into the Cat kit.
You don't need Belzona to seal oil. Buy $20 worth of brake cleaner, and $5 worth of JBweld, warm up the casting and apply to both sides. If you hadn't drained it already, put a small vacuum pump on the vent, clean the outside with brake cleaner, warm it up a little and JBweld the outside only with the vacuum running a couple hours to cure.
Hey onfoot, come by Precision Engines (40 MacDonald Rd, Whitehorse) on Monday and ask for Ben in the component shop. We should have some Belzona kicking around we can supply and I'd be more than happy to come take a look at ol' Hanna with you. See if we can't get the old girl sealed up. Cheers!
Brilliant idea Delmer.
Thanks! Not sure if I can get by tomorrow, but Tuesday for sure.
Do not use heat with brake cleaner on spray it on heated parts!!!!!! Always have good ventilation using brake cleaner especially under equipment. If a weld leaks oil it is not a sound weld, either cracked or bad porosity. All these homeowner epoxies fixes are guaranteed to fail on a bad weld. Have the welding outfit take a look at this and they should bs able to make a leak free weld. Good luck Bob
Yes, never mix chlorinated/ non flammable brake cleaner with welding or heat, it can make poison gas. The flammable stuff is just flammable.
Good safety message about brakecleen. I know it sounds hokey, but Belzone is the real deal. I saved many 3306 blocks from the scrap heap and tens of thousands of dollars with it. NC Machinery had a program called STAR. The STAR engine rebuild came with a extended warranty backed by mother Caterpillar including cavitation corrosion repairs made with Belzone. Times change. We don’t even talk about cavitation corrosion today. Who needs to, when a MX13 goes 75k and a Cummins x15 goes 250k before the block needs replaced.
I would say that the difference between replacing missing material on a cylinder block resulting from liner cavitation and attempting to stop this leakage using Belzona or anything else non-metallic is stress. The differential case is a stressed component in the area where the Belzona would be applied, the cylinder block isn't stressed to anything like the same level. For that reason if there is a porous area of weld or an incipient crack down below the surface right now, sooner or later it will break out and the results may not be pleasant. I would side with others who have recommended a weld repair. It may well be that aerosol crack detector reveals that it's only a small part of the length of the weld that is leaking. If that is the case it ought to be a relatively simple matter to carefully grind that small area out to eliminate the crack and re-weld it. Question to the OP. Before disassembly was it possible to see exactly where along the length of the crack the oil was leaking from.?
For sure. I agree. Especially if it cracked again. If not cracked and just a leak from porosity, I wouldn’t try welding on a 50 year old casting that has already been welded on. Too risky. So, what’s the status with Hanna?, Onfoot. Is the old repair cracked or not?
Agreed no way I would put any more heat or welding rod into that old oil soaked casting or take any more chances of slag going into a bearing I would probably use epoxy on the inside and rtv slathered over the outside and run for another 50 years
Here's the latest on Hanna and the crack. I spoke today with a fellow who is supposed to be one of the best welders in the Territory at Mobile Maintenance ( https://www.mobilemaintenance.ca/ ), showing him the photos and discussing options. He said that re-welding would be a crap shoot. It might work, but would just as likely it worse. He also noted how welding cast steel, unless done appropriately (which he explained at some length), would almost inevitably leave small imperfections that would lead to (in my case) leaks. From looking at the photo, he had no doubt that the weld was not appropriately done. Sigh. He suggested going with an epoxy, but was unable to suggest any in particular. He also suggested grinding the exterior weld to flatten and make for a better surface to bond the epoxy. I was concerned about weakening the crack. He did not see that as an issue. Which leads to the conversation I had with a representative for Belzona. I was asking especially about Belzona 1161. The rep said that Belzona would have been perfect IF it had not already been welded. The Belzona would not, he assured me, adhere to the weld. In time, it would just peel off. His suggestion was to check out a competitor: Defcon Tungsten metal epoxy. He also said that I should use a heat lamp to sweat out the oil in the cast steel pores. I.e., clean with brake cleaner, then put it under a heat lamp for 3-4 hours. Repeat at least a couple of times, leaving the heat lamp on overnight for the last time. Oh yeah, and to be sure to thoroughly rough up the previously applied epoxy on the inside of the diff. Tomorrow I am going to call the technical support lines at Loctite, JB Weld, Permatex and Defcon and see what I can learn. I'll let you know what I find out.
I might add that the minimum amount of Belzona one can purchase is a 1kg container--running about CDN$440.00... Jonas302, not sure what is the RTV you suggest slathering all over the outside...
Something like pematex ultra black not really the intended application but its flexible and sticky, easy to apply I've seen it used on a cracked diff of a 140G
Hmmm. This might just be the ticket--if it will adhere to the interior surface. If I rough up the epoxy coating and sweat the oil out of the cast iron, it should adhere, I should think...
Dream on. Bob
Onfoot, Thanks for the update and sharing the response from Belzone. Good to know. I realty think any RTV would turn to goo inside an compartment subjected to submersion in gear lube.
Why not try running a heavier viscosity oil and see if the leak improves? The results may point you in the proper direction for a more permanent fix. I personally would want to know if the crack is opening up under load or not.
Thanks, Vetech63. I'm running synthetic 75W-90 gear oil. When it's below -20C (let alone below -30C), heavier viscosity can be a serious issue. So far as I can judge, the crack is not opening under load. With cast iron, there really is no flex. If it was opening, it would be failing utterly, I should think.
That housing is not cast iron but is cast steel and is not that hard to weld., it will not heal itself and no amount of goop will stop the leak. The pictures of the old welds are of a **** poor job. there will be a fair amount of side pressure because of the ring gear side thrust and it should be properly welded. Bob
I am grateful for your thoughts, Bob. And I take your point about not being cast iron, but cast steel. I am going to call the Caterpillar metallurgy folks tomorrow in Mossville, IL and see if they have any wisdom. They will at least know the precise carbon % of the diff, I hope. For what it's worth, I am not a welder. And one of main welders at our local heavy equipment metal fabricating outfits told me that it he would be happy to weld it, but thought it would be a crap shoot if it worked and that it might make it worse. Perhaps he is wrong, but I cannot risk making it worse. After speaking with a Permatex chemist today, I cannot but think that Permatex Spray Sealant Leak Repair ( https://www.permatex.com/products/adhesives-sealants/sealants/permatex-spray-sealant-leak-repair/ ) on the outside of the welded crack might be sufficient to stop the leak. At the very least, it won't make it worse. No argument that the current weld is a **** poor job. But it is what it is. It preceded me by a good many years.
More great advice. Buuut !!!! I found some old Bazooka Bubble Gum on my bedpost.... Sorry had to.... Hows the Hanna coming along ??? ... I'm on pause for today my back is angry with me
Fat Dan, hope your back gets better. Thanks for bumping this thread. I agree. We need an update on Hanna. I’m OOS, as well. Just choked down the first two tablets of a z-Pac and a couple snorts of steroid spray. The China Flu is trying to kill me. Day10.
I have a friend who posted in another thread about being sicker than sick, and the last thing he said was this thing is for real! It was all I could do to keep from saying no **** Sherlock
No No nothing that bad but it is the worst case of Lumbago my doctor's ever seen LOL. Might even say it's terminal not so much that I'm going to die from it ... but I AM going to die with it... . I have a photographic memory; the problem is, it's on microfiche and the light is real, real dim now-a-days..
Coaldust , I hope your doing better soon After you Doc clears you Ol' family recipe for a Hot Totty: A.K.A Irish sweat lodge. 4oz. WARM water 1 jigger of bourbon, twist of lemon, pinch of ginger, 1 tbl honey. stir well and drink all at once.. Tastes like crap .. then go to bed and cover up. you will be socking wet in the morning from sweat and the bed close will be wet from sweat. Like an Irish sweat lodge.
Thanks Fat Dan! I appreciate the old family recipe. I’ll give that a try. I think it’s day 16, since symptoms appeared. The virus has run the course, but now I’m dealing with pneumonia. Good news is, I’m not dealing with any of the damaging Covid lung stuff the clinics are seeing in some patients. Just regular pneumonia at this point. Oxygen saturation is good. Waiting to hear what the Doc recommends next.
Glad to hear that you are on the mend, Coal Dust! Sorry to have missed a few days on the forum and just now learned of your brush with Covid. No small thing! Fat Dan's Hot Totty recipe may be worth a try. Hope that Fat Dan's back is doing better, too! Re. Hanna, I am waiting for the arrival of some Permatex Spray Sealant for sealing the exterior of the differential. The inside will be sealed with Glyptol 1201, which I was able to source locally. Challenge now is cleaning the interior of the crack as much as humanly possible from soaked in oil. Will let you know how it goes. Yesterday new glass was installed, replacing all the cracked glass in the cab. Doesn't affect how she runs, but she looks much nicer. Will let you know how things go, for sure. Thanks!
Thanks for your kind words Onfoot.; I'm in the same boat having a lot of projects going at the same time but the one I want to work on is on hold for a moment so it feels like I'm not getting anything done...
Might be a good application for JD Cornhead grease or grade OO grease. These are thixotropic (sp) that means they stay thick until in motion. The JD is not compatible with all oils but has fixed many leaking gearboxes on Bush hogs and stuff. I used grade OO for a leaking track roller. On the other hand if the casting is indeed cast steel and not any form of cast iron it could be welded successfully. Would need preheat, proper prep and any signs of old oil burned out. Grind old weld off because you have no idea what rod was used. Someone may have used a specialty rod when it wasn't really required. If the casting is cast iron likely has to come off and high temp. brazing would be a good option. Really sorry to hear of Coaldust and Fat Dan's health issues. It really sucks when you don't have control of what is happening to you or what others do regarding covid social distancing, masks etc. Let's us all just get better!!!
Interesting suggestion about using 00 grease. I have a call in to Amsoil asking about their 00. But only if what I have done proves unsuccessful. As I reported on the ACMOC site, Hanna's differential is once again filled with gear oil. It's been a couple of days and just a bit of movement (no work). So far no sign of any leaks. On the inside of the diff, the crack was painted with several coats of Glyptol 1201 enamel ( http://www.glyptal.com/glyptal_products.html ) and allowed to cure with a heat lamp. The exterior of the diff along the welded crack, after being thoroughly cleaned, was coated with several layers of Permatex Ultra Black silicone ( https://www.permatex.com/products/g...m-oil-resistance-rtv-silicone-gasket-maker-4/ ) and allowed to cure. My hope is that the Glyptol will have penetrated and sealed the crack on the inside and that the Ultra Black silicone will have sealed it on the outside--while remaining slightly flexible so as to not crack itself. Today I changed oil and fuel filters (and crankcase oil, of course. Am working my way checking the various gear boxes, making sure that they have adequate lubrication. Need to swap out the front tires for a mounted pair that came with Hanna. Almost ready to put her to work. (I think there must be about a zillion grease fittings!)