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Hi all,my welding rig began developing a major oil leak within the past week. I am losing about a quart every two days. Upon a visual inspection I noticed a slight "tear/gash" shaped hole right above where the front axle passes under the oil pan. It is an old NATO military Unimog that has had a Ford straight six 300ci adapted to it.A mechanic friend of mine suggested that I need to pull the pan, weld it and then reinstall it. The problem is that on a unimog this is a major task as the cab must be removed before being able to access the engine in order to lift it clear of front axle. The pan cannot be removed by any other means.My inclination is to braze the hole shut. However I am concerned that I will ignite the oil in the pan and cause a fire which may cause damage internally.My mechanic friend suggests that I use a MIG welder and seal the hole by series of long tacks, bridging the gash and sealing it little by little, one tack at a time. He says that this way the metal will not remain red hot as in brazing and less likely to ignite the vapors.I would like to know if anyone has successfully performed such a repair in position as I am contemplating and how did you do it? My other idea was to run an argon purge into the oil pan via the drain plug. This would fill up the pan and should prevent ignition.I once (and only once) welded a gas tank using a purge running from a running car's exhaust into the tank being welded. I insisted to the welder who suggested it to me that he stand next to me while I weld it. If he had flinched at the idea I would have backed out of the job. He didn't and the repair went flawlessly. I was much younger then and doubt I would have the balls to do it again. However it taught me the power of a non-flammable purge gas for repairs like that. I have only used water to fill a gas tank for welding on them. An oil pan is much less volatile than a gas tank.Any thoughts on this one?As always, thanks for your help,Tony Attached ImagesLast edited by therrera; 07-12-2011 at 11:45 PM.Reason: to upload pictures of my rig
Reply:I stick welded (7018/1/8") diesel tanks on oil rigs, full tank, w/o a purge. It was standard practice at one time, don't know if they still do this or not. I've also used the method with the exhaust on gas tanks with standing gasoline many times. I think you'd be money and time ahead taking your friends advice. IMOOnly when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money. -Cree Indian ProverbSA 200 LincolnVictor Torches
Reply:If you aren't going to pull the pan why not just half *** it, clean the surface real well and glob on the JB Weld.
Reply:You will have a nightmare trying to keep contamination at bay. As soon as you begin to heat the pan, the solidified oil thats left in the pan will want to leak out and contaminate the bead. I don't see an easy way to solve this issue short of pulling the pan and cleaning it. My guess is you will be chasing pin hole leaks all over the place trying to do this in place. In the long run I'd bet it's easier to pull the motor..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:red green ...Duct tape.....I forgot how to change this.
Reply:Originally Posted by SetzerIf you aren't going to pull the pan why not just half *** it, clean the surface real well and glob on the JB Weld.
Reply:i can say i was trying to cut a hole in an oil pan to junk an old engine (shows theres no oil in the pan) and i hit it with the torch, and BANG it split the valve cover right along the flange. Apparently cutting into the pan flashed the oil in it and caused an explosion that popped the valve coverVantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Originally Posted by Dualiei can say i was trying to cut a hole in an oil pan to junk an old engine (shows theres no oil in the pan) and i hit it with the torch, and BANG it split the valve cover right along the flange. Apparently cutting into the pan flashed the oil in it and caused an explosion that popped the valve cover
Reply:Hello all,thanks for the quick responses. They gave me various ideas, questions. I lean towards NOT pulling the engine for the simple reason that it requires a large hoist (or access to a fork lift) that can straddle the cab and then with a chain fall or other type of device lift the cab free of the chassis. Then a second hoist is needed in order to lift the engine to remove the pan.This is a daunting task and the last time I did it was 10 years ago when I put the Ford straight six in her and converted her into a welding rig. With everything in place it is probably a two day job considering the other things that must be removed to accomplish this (radiator, starter, linkage, disconnect wiring, etc.)Then the issue of money and down time. I will need to rent some location that has these things or take it to a mechanic shop and be prepared to foot the bill. I am not in that position. If I have no choice (because it is really the ONLY way to go about it, I can borrow the money from friends and family which will increase my stress level a bit more than it already is in these hard times.Having said these things, my questions are:For gizzardgutz: The suggestion to take my friend's advice: He told me two things. First I should pull the motor out to repair the pan. Then he told me that I could use a MIG welder to seal the hole. Which advice do you recommend I take? Pull the engine or use the MIG welder approach?Also, when talking about the purge approach: Are you saying that it could be brazed in place with a purge? I never tried to braze an oily part like this. I have used 6010 many times to weld through grease, oil and rust when making repairs during my steel mill welding days many years ago.For DSW: What if I took the welding approach in steps? That is, clean it well, put in a tack, then clean it again, let it cool, then put in another tack, clean it again, and so on. This way, the heat will be instantaneous, fuse the metal BEFORE the stuff would have a chance to get hot and drip down into my puddle. What do you think?To GBM: You may be on to something here. The fact that you have done these types of repairs lend a lot of credibility to your suggestion. My only concern is that it appears that the front axle "bottomed out" and hit the oil pan. Since this is not the stock engine I think the oil pan location and shape will make this likely to happen again. The JB weld approach may not be able to take the pounding if I bottom out again or repeatedly, whereas the metal repair would. Don't you think so?Thanks,Tony
Reply:Tony, LOL.... no I do not think the JBWeld would stand up to an axle repeatedly hitting it... but I also do not think that it is reasonable to expect a steel oil pan to do that either...( I think the picture you provided proves that point ) perhaps you need to be looking at modifying the shape of your oil pan to get around that axle movement hazard...Last edited by GBM; 07-13-2011 at 01:00 AM.Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Originally Posted by therreraFor DSW: What if I took the welding approach in steps? That is, clean it well, put in a tack, then clean it again, let it cool, then put in another tack, clean it again, and so on. This way, the heat will be instantaneous, fuse the metal BEFORE the stuff would have a chance to get hot and drip down into my puddle. What do you think?
Reply:Can a patch be used so you don't have to weld near the split? If one could be used I would use mig and weld small stitches and let it cool between them.Leo
Reply:What kind of patch is going to stand up to being hit by the axle ?Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Hello everyone,Thanks for your feedback on this. Remember that this oil pan has stood up to 10 years of use. I usually am very careful about NOT letting my rig bottom out like this as a matter of principle so as not to tear it up.However there are several instances where it very obviously bottomed out on me when going over speed bumps here in Phoenix, specifically on the street where I live and have to cross over them repeatedly. Due to the heavy winch mounted in front, there is a tendency to want to bottom out when hitting some type of bump.This I can control and especially now that I am aware that this has happened by just making sure that I am extra cautious of bumps in my path and slow down when going over them. This speaks to the issue of repeated bumps.I think the idea of welding a patch over the area seems to be a good one too. In fact I could do this with a 3/32" 6010 rod. What do you think of this approach?6010 can resist unclean surfaces, it is a fast freeze rod that will let me control the heat at the puddle by whipping motion. I think I am narrowing my thinking down to the use of say a 50 cent size patch and welding it in place with 6010 rod. I could cut one out with a hole saw and seal the hole prior to putting it place. Or I could cut a rectangular one with a cutting disk and round the corners, tack it in place on one edge and then heat it and pound it so it conforms to the shape of the pan. Then weld it out. It seems the worse that can happen is that I still get a leak but I buy time to get the money together to make the repair correctly, no?Any thoughts on this?
Reply:My thoughts, for what it's worth...Invest the time and pull the motor. Do the repair properly or even bolt in a new(er) oil pan.While you have it out refresh anything else that needs it.While you're at that, would it be possible to modify the motor mounts to raise the mill some to reduce the likelihood of further axle interference? If that isn't feasible, what about a slight suspension lift to accomplish the same? I'm assuming this Mog has portal axles, not sure how liftable the suspension is..."These instructions are at our present level ofknowledge. Legal requirements do not exist.Technical issues subject to change."_________________________________________Lincoln MIG PAK 180Lincoln AC-225
Reply:Well I recently have had some experience in trying to fix a slowly rusting away oil pan that I didn't want to replace (because the truck wasn't worth it). I used 2 part epoxy and it worked (kinda, for a while) but just kept leaking because the rust was keeping ahead of the repair. Ultimately had to spend the 100 bucks and couple hours of my time, on my back in the driveway, in winter and replace the pan. SO although your problem is slightly different your problem is that you have and alignment issue that will need to be resolved. SO drain the oil, brake cleaner the area, sand to roughen and epoxy patch to get by for a while. Then baby it till you have time and money or another reason to have to do engine work or perhaps in time you will go a different route. Thats my two cents worth and no guarantees. AND since HE was mentioned "If the women don't find you handsome, they should at least find you handy" RED GREEN.Miller thunderbolt 250Decastar 135ERecovering tool-o-holic ESAB OAI have been interested or involved in Electrical, Fire Alarm, Auto, Marine, Welding, Electronics ETC to name a just a few. So YES you can own too many tools.
Reply:If you do it right, the oil wont ignite, I had to do a temp fix on my mustang once because the oil jockey fubard the drain plug on my oil pan.. took my time and nothing happened.. it was just a temp fix though, as I was pulling the motor in a couple months.. small bead, let it cool, small bead, let it cool.www.thefusionsolution.com
Reply:Originally Posted by dumb as a stumpAND since HE was mentioned "If the women don't find you handsome, they should at least find you handy" RED GREEN.
Reply:Use a shop vac and hook it up to a valve cover, that will keep the what oil is left in the engine and also suck the JB weld in if you go that way,I welded a full hydraulic tank below the fluid level by sandblasting the crack which peened the crack shutand ran a quick bead over it, the a good weld
Reply:Originally Posted by speedfreak87If you do it right, the oil wont ignite, I had to do a temp fix on my mustang once because the oil jockey fubard the drain plug on my oil pan.. took my time and nothing happened.. it was just a temp fix though, as I was pulling the motor in a couple months.. small bead, let it cool, small bead, let it cool.
Reply:Originally Posted by RJ LindblomIf you do that, leave the oil in making your fix and change it right away to catch any contaminates? It would be the vapors that would ignite or make it more likely for ignition.
Reply:Originally Posted by scooter383Use a shop vac and hook it up to a valve cover, .....
Reply:Originally Posted by GBMI do NOT think most shop vacs have explosion proof motors... the vapors or fumes from the oil could ignite...
Reply:I've welded high pressure street elbows which fit into a hydraulic cylinder while the cylinder was FULL of hydraulic oil. I believe an empty cylinder would be dangerous because of the presence of oxygen.The bead will tend to turn to steam because the oil cools it, and it will try to blow out the metal.While it's ugly, you can repeatedly go back over the weld, and seal any pinholes caused by the steam blowouts. Let it cool between passes, and try to wipe off any oil (hard to keep it clean, but at least it gets rid of excess stuff which can drip down while on fire)The only oil which caught on fire was the oil which seeped out of the pinholes while actually welding. Nothing inside the cylinder was affected. There's no oxygen in a full cylinder, or below the surface of the oil.It's not ideal, but it can be done"Any day above ground is a good day"http://www.farmersamm.com/
Reply:If you're afraid of welding..............There are excellent kits made for sealing gasoline tanks. The adhesive resists the solvent effects of the gasoline. The tank should be drained (same with oil pan), then the adhesive and fiberglass mesh is applied"Any day above ground is a good day"http://www.farmersamm.com/Well, the 'right' way is to pull the pan off and clean it and then braze or weld it (patch or not) or replace the pan. While the pan is off, reshape the pan or the suspension or the motor mounts or the bump-stops (or some combination of all of the above) to keep the pan and axle from trying to occupy the same space at the same time. Sometimes epoxy-type goop fixes are the way to go. Sometimes they aren't. I think this case is one of the latter.IMHO. The best laid schemes ... Gang oft agley ...
Reply:As an Engineer performing prototype,design and testing activities for an OEM construction equipment manufacturer for 18 years, I have been involved with welding on used hydraulic oil tanks and cylinders over the years with no issues. Make sure the joint is as clean as possible, make sure the tank is full of oil. Use a mig welder set for 12-10 ga. material thickness. Spot weld the entire crack to build up material. Smooth the joint down with a grinder or rasp. Then re-weld with a continous seam with a little higher weld setting. This will work to your complete satisfaction. It is the oil vapor or primarily presence of fuel vapor in conjunction with oxygen that makes tanks go BOOM when being welded on. If submerged, not and issue unless you blow a hole through the pan. THat will be fire rather than boom, at least initially. Put a spacer or bump stop in place to limit axle travel to eliminate contact with oil pan for the future. This should last for a long time. I have never had successful repair with J-B weld on anything. That stuff is a joke in my opinion and gives people a false hope of something accomplished. An alternate approach to welding would be to create a fiberglass patch rather then the gray gooey crap. The resin and fiberglass mat will etch into the metal and bind to it. The question I would have here is temperature effects. In regards to using vacuum, (shop vac) on an oil tank to keep the oil in, this is a common procedure on assembly lines when a bad fitting or hydraulic line needs replaced on a brand new machine being built during the end of line inspection. Things don't go boom. The exception might be on an engine with fuel vapor present in the crankcase. Diesel, not as much of a concern. Good luck and let us know how it goes.
Reply:Hi all,these are all good comments and ideas. However some of your suggestions are based on the assumption that the hole is below the oil level and therefore not subject to ignition due to lack of oxygen.The tear / gash is at a point just probably level with the oil in the pan. When I replenish the oil to make up for that lost due to the gash, it drips out horribly, steadily until it reaches the point where the oil level just meets the gash. It easily drips a couple of ounces each time I park somewhere with it.Thus I am dealing with vapors here and the danger of ignition. However I know that oil doesn't just ignite immediately having done many repairs and welds in oil soaked environments (on equipment, etc.) during my time welding.Therefore I am inclined as I mentioned to weld on a patch as opposed to trying to seal the hole. This way the arc will not come in direct contact with the opening. The patch's edges will be beyond the opening and the area that will get red will do so for a few seconds as I let it cool down before repeating the precess. I prefer using a 6010 rod for it's contaminant "resistant" properties as opposed to a mig which will give me porosity at the slightest hint of a contaminant.Here's a question: How do I go about putting a fire out if it should happen? The Unimog's ignition has two settings. The first activates the starting mechanism and accessories and starter switch but will not send a spark to the plugs. This allows me to crank the engine over repeatedly without actually starting it.Would you recommend doing this should I suspect I started a fire in the crank case?I don't have a shop vac but a regular house vacuum cleaner. I could adapt it to the oil filler neck on the valve cover as suggested by scooter383? I could remove the filter canister that captures the dirt so that the sucked in air simply escapes into the environment, vapors and all. Theoretically.Also while on the subject, I think I will change out my front shocks as the stock ones are originals and are probably over 40 years old! This should help prevent her from bottoming out, don't you think? I will also look into how I might shim the axle so it hits it's rubber stops sooner and maybe prevent the bottoming out.Thanks for your help,Tony
Reply:What about trying this process?- Cut a patch from sheet metal that covers the hole with a few inches of margin- Shape the pan and the patch to get as good a fit as you can - the goal being to reduce leakage during welding- Press the patch over the spot with clamps, magnetic or steel cable with loops that you can tighten up with a ratchet strap for example- Over fill the oil to reduce the chance of vapor igniting (you can always drain leftover excess when you are done)- Weld the edges of the patch to the panUsing the patch might buy you a little more time and reduce the amount of oil seeping into the welds. There are real limits to what the 60xx series rods can cope with - metal running over with oil sounds close to the edge to me (oil is a hydrocarbon and is certain to introduce porosity).Another approach would be to over fill the oil (drain it off later) - jam the rod in and get the seal mostly sealed, clean and cap it with additional weld that might be less porous than the first pass since there would be less oil running over the part.Hobart LX235Victor 250 Oxy-Acetylene Rig (welding and cutting)Bobcat 773F-350, 1999, 4x4, 16' 10K# trailerOutdoor Wood Burner - 10 cords/year
Reply:Originally Posted by therrera . . .Here's a question: How do I go about putting a fire out if it should happen?. . .
Reply:If you are gonna weld in situ, take a Co2 tank and set to 10-15 cfh and place the hose end in the dipstick hole or breather hole. Allow 15 minutes for the Co2 to displace the atmosphere (forces it up & out) and go to it.After a while the Co2 will spill out the top and gather at ground level so you need air movement if you're laying on the ground.Matt
Reply:Gott agree. I've got a F-350 7.3 L diesel and they are notorious for holes in the pan. Cost to do it properly is about $1500 as the motor has to come out. Some guys cut the cross member, put a new pan in, and then weld, or bolt the cross member back in. I went the JB route 3 years ago. This truck is in Atlantic Canada, known for it's salt distribution on winter roads,and it'a plow truck to boot. JB is holding up just fine. Originally Posted by SetzerIf you aren't going to pull the pan why not just half *** it, clean the surface real well and glob on the JB Weld.
Reply:Would it be possible to remove the front axle, then take the pan off from the bottom? Axles are pretty easy to get in and out.Miller 250x & Lincoln V205-TSmith Oxy-Prop torch
Reply:Originally Posted by ChuckWould it be possible to remove the front axle, then take the pan off from the bottom? Axles are pretty easy to get in and out.
Reply:Hi all,I am at home working in my shop and taking care of some walk in clients with a variety of welding tasks. My rig is sitting in my yard waiting repair which I will be getting to shortly.Thanks again for your ideas. I like the Co2 route. I happen to have a cylinder laying around and can rig it up in this fashion. This should displace any oxygen in the crank and pan at least enough to head off ignition.I should get a fan (which I also have laying around) next to where I am welding to move the gas away from me as I'll be right under the gash.While its filling up, I'll cut a 50 cent sized patch and tack and fit it into place in several spots, using a torch to soften it up so I can hammer it to conform to the shape of the pan and weld away.In fact I'll check to see if there are any other ideas and get to it within the hour if not. I am reluctant to go the jb weld route only because it may be subject to more impacts over time and can visualize the jb weld cracking and losing its seal.Thanks again,Tony
Reply:Originally Posted by DSWMig is notorious for cold starts. Mig is usually not the 1st choice for seal tight welds because of this. Your tack, tack, tack will probably leave you with a bunch of pinhole leaks from poor fusion. I also question how "clean" you will be able to get this, and exactly how you plan to do so. Breakleen while it does a good job on oil, produces phosgene gas which can be deadly when heated. Acetone is extrodinarily flamible. I'd bet that if you let this sit for say an hour to dry, you'll find the oil has reapeared from the crack and you need to do this all over again. Pouring a solvent down from the top to rinse out the pan and remove the oil, has bad idea written all over it for any number of reasons.
Reply:Hello everyone,I am going out back right now and start the repair. I will go the Co2 route and may braze or weld it with 6010, we'll see.I'll post some pictures.Thanks,Tony
Reply:You waited until after I suggested the JBWeld to tell us how the injury happened...and that you were not going to do a structural fix which would keep it from hitting it again.... if you had said that up front I would not have mentioned the JBWeld....Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:If you weld it keep an eye out under the truck. Oil and transmission pans are brittle and it's not uncommon for them to crack after being welded. Brazing the hole or patch negates this.Back before everyone knew better it was quite common to repair the pan on the vehicle. I've seen it done numerous times and have done it myself several times over the years. Never saw a fire either. Not saying it can't happen, just never encountered one. I have repaired several oil tanks and diesel tanks with no purge and seen many others repaired while working close on another project. Same deal. No fires.Last edited by Oldtimer; 07-13-2011 at 08:45 PM.
Reply:Originally Posted by farmersammI've welded high pressure street elbows which fit into a hydraulic cylinder while the cylinder was FULL of hydraulic oil. I believe an empty cylinder would be dangerous because of the presence of oxygen.The bead will tend to turn to steam because the oil cools it, and it will try to blow out the metal.While it's ugly, you can repeatedly go back over the weld, and seal any pinholes caused by the steam blowouts. Let it cool between passes, and try to wipe off any oil (hard to keep it clean, but at least it gets rid of excess stuff which can drip down while on fire)The only oil which caught on fire was the oil which seeped out of the pinholes while actually welding. Nothing inside the cylinder was affected. There's no oxygen in a full cylinder, or below the surface of the oil.It's not ideal, but it can be done
Reply:Hi TonyI couldnt get through all these posts, some of the responses were not the best.Anyway, brazing it is the way to go.I've done a couple of dozen oil pans, normally to replace the plug. Saying this, now with all my experience, I would put some CO2 into the crankcase and close off all the caps. Drain the oil and clean the pan as well as you can and try not to get it to hot. Have fun ))
Reply:Hello all,I just came in from brazing on the oil pan. After setting up the Co2 bottle as recommended by Matt_Maguire and buggy_man. It worked like a charm. No oil fire started and the only burning oil was on the outside, coating the oil pan or that dripped out while I was brazing.I chose brazing because after looking at the gash it seemed that it would close up with one pass of the puddle. It went like that until I got to the lower part of the gash where there was actually a hole that required building up and filling in to close.Everything went fine until I got to the last part of the hole and closest to the existing oil level. I assumed I could just close it up without draining the pan and what I found out was that the lower part of the hole was in contact with the oil and it was being cooled.Not wanting to stop, drain the oil and continue again I persisted and cranked up my flame so that I could compensate or so I thought. To no avail. The brass would not flow as the pan absorbed all the heat I could throw at it. After about 20 minutes of that, I gave up. The pan had won, for tonight.Tomorrow I will drain the oil, fill the crank again with Co2 and finish the job. I have an appointment in the late afternoon about 30 miles from my house to weld on an old Volkswagen chassis. Going to get it done just in time. I feel very relieved and grateful to my welder brothers who took the time to offer their help. I am in your debt.I will take some pictures after I finish tomorrow. I started to take some tonight, but my camera's batteries died so I will have to recharge and take them tomorrow.Just for the record. I seriously considered the JBweld option but decided that if I could perform a metallurgical repair it would be longer lasting and also withstand an occasional bump from the front axle. However I will make it a point to carry some with me as I now can appreciate the fact that it has its place in the repair world. There are many times that I recommend to a client to bolt or screw something down instead of welding. There is the right tool for every job and the right procedure too.I am going to see if I can find some affordable shock absorbers for my truck to beef up the suspension and hopefully prevent the bottoming out I have been having lately. It could be that my shocks have finally given out and all I need to do is get new ones. I will also see if I can put say a 3/8" shim on my current rubber front axle stops to not let it ride so high into the engine. since the pan is already "molded" by being hit by the axle, shimming it should make it conform to the axle's shape yet hopefully stop it when it approaches too close.Thanks,TonyLast edited by therrera; 07-13-2011 at 11:02 PM.Reason: to correct a misspelling and add some more info
Reply:Can you unbolt the pan, wiggle it around and drop it down enough to get your hand on the inside even if you can't totally remove it? Then you can clean the inside and do a more proper repair. Also with the pan unbolted you'll have more area for pressure to escape should anything ignite. With the pan loose and cleaned inside and out, I wouldn't be worried about doing a proper weld and getting up to a high temp.Dynasty200DX w/coolmate1MM210MM VintageESAB miniarc161ltsLincoln AC225Victor O/A, Smith AW1ACutmaster 81IR 2475N7.5FPRage3Jancy USA1019" SBAEAD-200LE
Reply:Hello all and thanks for the help.I just came in from brazing the rest of it out using the Co2 approach. It worked like a champ. I just filler her with oil and ran her for 1/2 an hour. Not a drop leaked.I'll post some pictures tonight.Thanks,Tony
Reply:Originally Posted by Matt_MaguireIf you are gonna weld in situ, take a Co2 tank and set to 10-15 cfh and place the hose end in the dipstick hole or breather hole. Allow 15 minutes for the Co2 to displace the atmosphere (forces it up & out) and go to it.After a while the Co2 will spill out the top and gather at ground level so you need air movement if you're laying on the ground.Matt
Reply:Hello all,here are the pics of the final repair. As I mentioned last night, it went smoothly once I drained out the oil. Before that, the brazing laid down well until I got to the oil level and where there was a hole. The upper part was more of a crack/gash. The oil cooled the weld zone so I couldn't build up the needed heat to bond the brass to the pan. I chose to fill the hole directly instead of using the patch since now I wasn't worried about welding directly into the crack/gash/hole and starting a fire. The logic behind the patch in this repair was to not weld directly at the damaged area, but around it.It was somewhat of an awkward repair as I did not have good torch angle with which to manipulate the puddle and put down rod in a continuous bead. So I had to heat and fuse a puddle at a time. When I got to the actual hole that resisted me yesterday I had some difficulty building up around it as I would get it too hot for lack of moving space and I would lose the brass which would drip down and expose the hole again.I had to modify my technique to add brass from different angles, from above, below, from the sides to add a little bit at a time and seal the hole and finally run a "cover" over it all.Looks kind of rough but I'll take it! The brass flowed downwards beyond the actual damage. The crack and hole was smaller than what the brazing would imply. These pictures were taken after I had driven her almost 50 miles round trip to do an after hours job for a client yesterday, not a drop spilled. I came home too tired to go out and take pictures to post as I had said I would. Sorry about that.I have performed repairs like this in position before with my TIG on aluminum fuel tanks for big rigs or on oily transmissions and even on aluminum and steel oil pans. I almost always started a fire (flame) and would stop welding to blow it out lest it get out of control. My fear was that it would begin to burn fiercely and run the risk of starting a fire.I also have had the pan "whoosh" on me (when the welding would ignite the fumes) as described by someone earlier in a post. I asked for help because in my older years (61 in a few months) I find myself more conscious of my mortality than when I was younger. That's what prompted my request for help and I appreciate your responses. This is the method I will use to repair such damage in the future. I will keep the JB weld approach as a backup when for whatever reason welding or brazing is not possible.The pictures show also the tank and regulator feeding Co2 into the oil filler neck. I waited about 15 minutes as suggested and went at it. I didn't setup the fan, figuring there was enough open space and air around me plus I was situated off to the side for most of the brazing.Thanks again,Tony Attached ImagesLast edited by therrera; 07-15-2011 at 11:23 AM.Reason: to add some more detail
Reply:Originally Posted by SetzerIf you aren't going to pull the pan why not just half *** it, clean the surface real well and glob on the JB Weld.
Reply:Cleaned the outside on the F-350 after draining and let it sit for two days before putting the JB on the pan. Wanted to ensure it was good and dry (no oil coming out of the holes). That was 3 years ago and it's holding just fine... Originally Posted by KelvinYep, that's what I was gonna say. You'll need to drain the oilpan first to ensure the epoxy gets a chance to harden good before oil gets to it...
Reply:Hi Everyone,I'm looking for some kind of advice. I have an Audi A4 that is leaking some oil. Perhaps up to a quart a week. THere's a smal hole/crack on the bottom of the oil pan. The stealership has quoted $670 for replacing the oil pan, but i've been reading that TIG welding may do the job just fine.If I decide to go this route, who would I call? An auto Body shop? a regular mechanic? Who would have such tools for welding? I would appreciate if somebody could point me in the right directionAlso, what should I expect to pay to have this done by a welding professional?Here's what the damage looks like.
Reply:Hi rtg,Is the crack where I show the arrow? Looks like it, I'm just double checking. That kind of repair is very difficult in my opinion for several reasons, the most serious being the contamination of oil that will be present inside the crack that will boil out when welding is attempted. If this were a steel pan I think it would be an easy fix, but I think its aluminum and any contamination turns the job into a living hell.The second thing is that anything that will melt (o-rings, gasket material, etc.) that is in the vicinity will be toast no matter how careful you are because the heat needed to fuse will spread to the region fast.Finally, to weld it will require disassembling it, like that pipe in the picture. Is that the dipstick tube? Is that tube part of some oil pickup or is it pressurized. The crack may go into a channel. I try to drill cracks out and then Vee them before welding them up.I think any mechanic shop can pull the pan out, clean it and call in a welder or take it to a weld shop where it could be done on a bench. Taking it out and putting it back in is where most of the expense will be depending on what is required to pull it. On my truck for example, the engine must be lifted to remove the pan. To do so, the cab must be taken off so it becomes an expensive proposition.You could also try Craigslist to locate a welder. I get called in to do jobs like this regularly and they find me on Craigslist. I don't recommend trying to do it in position.You should post this in a new thread under "projects". More people will be attracted to respond I think as opposed to this old thread.Hope this helps. Attached ImagesLast edited by therrera; 02-02-2012 at 12:33 AM.Reason: to add more info |
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发表于 2021-8-31 23:27:37