got a couple of belly pan bolts that were ruined before I owned them, 7/8", and wondered about just helicoiling them or drill out and tap 1"? I have never used the coils and wondered about how permanent they are. thanks..
I've never had good luck with helicoils in this situation. If you want to go this route, take a look at Keyserts instead. Either way, hand tapping 1" upside down is not easy. If you have the room, I would consider using the Cat idea of welding a loop of steel to the inside of the chassis rail and dropping a standard bolt through it.
If there is room, and the frame is flanged, weld a nut above the hole. Screw the bolt up through, put the nut on, snug it up, weld a couple of flats. Problem solved. My old Komatsu and Case had nuts welded into a box up above the bolt hole. Had to replace a few over the years.
thanks guys, somebody has already done the trick that Cmark mentioned on the other side. both your ideas sound better than tapping a 1" hole upside down..
I've never tried a helicoil on a belly pan, but I've had great success with them in other places. However, once you see the price of a 7/8 helicoil kit, you'll just buy another dozer.
Whatever method you use to remedy the problem, don't forget the final step when install the new bolts...Never Seize. One of the fellows I work around once told me "I see you use that stuff quite often". My reply, "if it doesn't get Locktite, it gets Never Seize".
Has anybody heard about the DOT not allowing Anti-seize on wheel nuts? My uncle told me that this winter. I do most of my own tire work, and have never had a wheel come loose. Hub-pilot or stud. I realize this is a bit of a swerve, just wondering since Anti-seize was brought up. BTW, I'd like to meet a man that would be willing to cut new 1" threads under a dozer. If there was such a man, I would be very polite to him. :salute
been there done that & dam sure don't want to do it again!!! but be very polite to me I have to agree with you willie almost everything gets a dab of never seize, if there is a chance ill have to remove it in the future im a big fan of locktite also cant have it coming loose either
The secret to cutting threads is A) Use a sharp tap! B) Use a tap adapter so you can drive the tap with a ratchet. C) Use the wax or grease type cutting lube. D) If it's hard going, you're doing it wrong, and see (A). I had one hired hand insisted on driving taps with a cordless, worked okay sometimes but it seemed to me he spent as much time removing broken taps as he saved versus hand tapping where you could feel the tap start to bite. Heli-coils are really for blind holes, on through holes you usually end up spinning them out the back side.
I have put in hundreds of heli-coils in industry and construction equipment and if they are drilled straight, and installed correctly, I wouldn't be a bit afraid to run them in my own equipment. Just my 2 pennies. Not bringing down anybody who hesitates to use them. BTW I use a cordless for taps everyday,but I won't risk it in anything above a 3/8.
I had to do 80 30mm in one day. Was using the impact by the end of the day. On your belly pan, I'd weld ne nut on the in side to keep the same bolt size for the pan. Will make it easier to track down a missing bolt next time.
I often say when asked why I like to use so much never-seize, "Make it easy on the next guy because he might be you!"
I find this interesting because anti seize actually allows the bolt to draw up tighter and get the proper stretch which in turn holds the wheel better. Without antiseize the torque is lost in the binding threads and doesn't really stretch the bolt properly.
I've put lots of 7/8 and 1 inch helicoils in, particularly blade braces but also dozer transmission mounts. I agree with lantraxco but would add that making sure the tap is going in straight is the biggest problem I've alway had. At times I've used a long extension on a ratchet and braced it so the tap can't walk side ways when getting started. I've seen ad materials at times touting the "new" coatings on the bolts that don't require lubricants in order to obtain the required torque specs on threaded fasteners. I suppose they are OK at the manufacturer's level for new stuff, but weather and dirt usually take care of them. Taking something apart and putting it back together again seems to strip off the miracle coating and you have to use a lubricant for the proper torque. I'm guessing that some wag at the state level was contacted by a sales rep and fed a load of "new coating" so they wrote another self serving law to write a ticket on.
Just to clarify my earlier comment, I don't have any problem with using a 7/8 helicoil per se. You can make a nice job and lube the bolt up, install it and all's good. The problem comes when the next bloke comes along and takes off the belly guard, drops the bolts in the mud, hammers them back in with an impact gun and after about three cycles of this, the now crappy rusty bolt will pull the helicoil out with it and you're in a worse position than you started with.
Cmark, Exactly, LOL.
I think we talked about this before. I use alot of anti seize but i have read in owners manuals lug studs dry torque to so much. I just bought a 1961 F600 it steal has a owners manual in the glovebox that covers F100 /F800s and it says dry on every thing but the F350s. I had a 61 F350 with the 6hole wheels and i had more stud problems with it than any thing i ever owned and they were hard to find back then.
HeavyEquipmentForums Little bit, I've got nothing to add, just keep my head down.
Thanks guys. Consider the wheel nut subject closed.