Hey everyone Just after some opinions......I am currently doing another D353 out of a D9G (an early one) this engine has the main caps with the split pin through the nut, I have rebuilt a few of these and I don't like the split pin idea so I don't bother to fit it, I think it is a waste of time and if the only thing stopping your main cap nuts from coming loose and dropping a cap into the sump is a poxy split pin I thing your in trouble! Just interested in a few other people's thoughts on the topic......thanks
Yair . . . Pathull . I always took them to torque and then on a bit to get the split pin through . . . at least you know they're tight. The Poms used to make quite a thing of this on the big low speed engines. The bolts were cross drilled (two holes) though and the procedure was a torque reading plus what was necessary to provide a slip fit for the pin. Cheers.
This engine has the holes cross drilled in it, the last D353 engine I did was a spacer plate engine out of a D9H being a later model engine it didn't have the split pin set up in it, scrub puller do u know of any old d9 engines up in qld?
The split pin was the equivalent of Loctite, belt & braces if you will. The torque applied to the nut should hold it under all normal circumstances, the pin makes sure it does. You really need tctractors or OM to chime in on this one. They're the boys for this generation of iron.
I wouldn't really call it locktite! You imagine a loose main nut chattering away on a split pin it would wear it through in about 10 min
If it's been tightened right in the first place it would never loosen enough for the nut to rattle on a split pin, basically because the pin diameter is so close to the groove in the castle of the nut. And even if it could it would take a lot longer than 10 minutes IMHO, more like years . ........ My comment re Loctite was meant in the respect that a lot of bolts you are 99.99% guaranteed that the torque alone will hold the bolt without loosening. You put the Loctite on it to get that last 0.01%
I guess if it has been tightened to the correct tension and would never loosen enough to touch the pin there is no need for the pin to be there! I'm not sure how far into the d353 serial numbers they went away from it but in the later d353 engines they don't have it same as the d320s ect 3304 and 3306 engines don't have pins
As I said before Tony is the man that will have the answer to your question regarding when it was done away with, but if it was mine it would be getting a split pin in it if it has holes in the studs and castellated nuts for the main caps. You don't give the engine S/N but a quick check of D9G 66A prefix reveals that for tractors up to 66A12015 the engine S/N was the same as the tractor S/N (old-style numbering system), above that the engine has its own S/N. Those engines are S/N prefix 97U and do not appear to have the split pin in the main bearing cap nuts, certainly the Parts Manual does not list one.
Yair . . . Pathull I have been out of the game for too long mate, no contacts anymore, Tilley's in Toowoomba would be a first contact. As Nige mentions tctractors, Old Magnet , kshansen, lantraxco and others will probably weigh in on this, I am just a bush mechanic and probably give comment where I shouldn't. Cheers.
Not that you see too many D9's flying around, but you could compare the use of secondary locking mechanisms such as split pins and castellated nuts to the use of lock wires in the aviation industry. Aircraft are assembled to standards that the average mechanic will possibly never see and rigid specifications, yet they still lock wire bolts and nuts as the ultimate insurance. Given that the locking pins do no harm, why wouldn't you fit them?
Good analogy, better than my Loctite one .............
hi Karl, I guess if the older D353 DIDN'T have split pins and the later ones DID it would indicate that there was a problem at some stage with main bolts or rod bolts coming loose, but as it is the other way around it gives the impression that caterpillar changed their design, the reason you wouldn't put them in (for con rods) the d353 is designed to have access through the side to avoid having to remove the sump to carry out for example an in frame rebuild. to remove the split pins from the intake side of the engine out of the con rod bolts is practically impossible! so if they don't need to be there I say leave them out to make the job easier for the next poor bugger trying to rebuild the thing in frame down the track! the early con rods also update to the later rods without the pins in the bolts
This is along the same idea as the sheet metal locks plates used on just about every internal bolt on engines, at least Cats, years ago. Then after many years of installing them newer versions of the same engine start showing up with no lock plates. Same for the split lock washers seldom find them being used on any of the newer equipment, just good hardened flat washers. Heck even my Harley engine has no lock washers holding it together!
Im pretty sure you cant buy a genuine split washer in the cats any more for the normal main stream hardware anyway I think the old split washer part numbers update to hardened flat washers
You won't feel that way if they come apart and it has been known to happen. From an old service bulletin,hope you can read it.....
If the manufacturer wanted the split pins in there maybe you should put them in.
Split pins, they can be a pain all ways, in the U.K. the likes of Leyland used split pins in every crack they could, the pins would shake loose if not installed correctly this being common to find on oil change bits of pin, the result was torment on the safety of the engine resulting in a sump off job, the bolts/nuts would always be found in good tight condition but the fix was to remove all the split pins and fit new items after firstly opening the pin legs 90 deg then closing them up to install them, this resulted in a side tension within the pin hole stopping the things rattling about, anyhow on CAT engines the correct pins are right fancy items with a shape and form specific to CAT I think, the not so happy bit is with the correct torque set on the nut the pin fails to line up needing a good pull tighter to get the pin in?? I will admit to always fitting pins if I find the little holes to stuff them in more from habit than concern the nut will undo, the more important thing to remember is rod number to the block window on the earlier engines, good D342 and D353 blocks are getting hard to find now, I know of a few that I keep my eye on. tctractors
Yair . . . Old Magnets Posted service bulletin extract echoes what I mentioned in my #2 post . . . at least you know they're tight and haven't been missed, back then white paint pen hadn't been invented. (grin) Split pins are all very well but the thing that made my life a misery were the lock wires Allis Chalmers insisted were necessary through the heads of the steering clutch flanges of the dry arse end HD 21's. There was a very specific procedure, two holes for the wire, and the angle at which the wire exited the bolt head was considered important. It had to be twisted between bolts so both chords were tight. Problem was there was no room for your knuckles and I had a series of small bent screwdrivers to get in there. To this day I have memories of working all one freezing winters night with a heavy head cold up and down, up and down adjusting the position of the tractor with the jacks, what a bloody nightmare. Cheers.
Cold for Queensland would be considered as anything under 20 degrees Centigrade (68 Fahrenheit) I suppose ........ :tong
That last paragraph sums it up in my mind. "We know they are unnecessary as a locking device" they go on to say they are just there to make one feel warm and fuzzy! On critical assemblies where there is a chance of missing one bolt or nut what I like to do is as each one is tightened to the final torque is just use a paint stick to put a dab of paint on the nut or head of bolt. Do the same thing when setting valves. Adjust, tighten nut, recheck clearance then dab of paint. This is real handy if you get called away for an emergency in the middle of the tune up. Another thing I always tried to do if I was half way through installing a component and got pulled away to another more important job. Just leave the wrench on the last bolt or fitting I tightened to remind me where I was when interrupted.
old magnet the service bulletin you have put up only states that the factory knows that they are unnecessary and are/were only still used as an indication to show weather the nuts had been tightened of not, that's is what a paint marker is for these days!
Yair . . . Gotch Nige (Big grin) It can get cold though. In that South West border country zero centigrade is common enough and I see a little further north it got down to minus seven C one night in 1987. Cheers.
-7 º C? that's almost 20 ºF heck around here that's still tee shirt and shorts weather right Grandpa?
Engineering standards were different way back when and a lot of procedures carried over even though materials science and engineering got a lot better. An engineer for a bolt company told me that they loved to sell them but didn't want anyone to use them. To me cotter keys work in places where a nut can't be pulled tight. Some control linkages such as throttle and transmission control cables and such. Lock wires are a carry over from before the grading of bolts and hardware. I had to use them when I was in the USNavy but have never seen them again. I don't even own a pair a wire winding pliers. Politics and money are the only reason they have stuck around. I have to agree that one of my worst fears is having reassembled a big expensive motor only to find the end of a cotter pin in the bottom of a drain pan at the first oil change. I used to use the lock washer issue as a way to test personnel. When I started running shops I absolutely forbid their use and made the bolt sales people take them all back. Then I looked for the wonk that jumped over my head to management and promptly marked him for release at the earliest opportunity.
While we are on this lock washer topic one thing that kind of seemed odd to me. If you assemble something with a combination of nut and bolt and use a lock washer under the nut, what is stopping the bolt from turning and the assembly falling apart? One could maybe make a case for lock washers when the bolt is going in to say a casting or the nut is being installed on a stud that is tight in the housing, but when it's a nut and bolt assembly ???? Back sometime in the early 1970's. After seeing so many new Cat machines coming through that just a few years back would have had lock washers and sheet metal lock plates on just about every fastener. I was in the process of doing a ground up rebuild of my old Farmal BN tractor. Well I decided to try an experiment for myself. Not one lock washer was used assembling this old tractor. Many bolts had to be replaced with shorter bolts due to the lack of the locks, the old ones were often the extra thick style. Well as of today when I was mowing the lawn with this tractor I have not seen one fastener come loose due to the lack of lock washers. If they make you feel better feel free to make use of them.
While we are on this lock washer topic one thing that kind of seemed odd to me. If you assemble something with a combination of nut and bolt and use a lock washer under the nut, what is stopping the bolt from turning and the assembly falling apart? One could maybe make a case for lock washers when the bolt is going in to say a casting or the nut is being installed on a stud that is tight in the housing, but when it's a nut and bolt assembly ???? Back sometime in the early 1970's. After seeing so many new Cat machines coming through that just a few years back would have had lock washers and sheet metal lock plates on just about every fastener. I was in the process of doing a ground up rebuild of my old Farmal BN tractor. Well I decided to try an experiment for myself. Not one lock washer was used assembling this old tractor. Many bolts had to be replaced with shorter bolts due to the lack of the locks, the old ones were often the extra thick style. Well as of today when I was mowing the lawn with this tractor I have not seen one fastener come loose due to the lack of lock washers. If they make you feel better feel free to make use of them.
Got to confess I still use the split pins on the old stuff, the real shakers. Not just any pin though. I use the largest one that will fit the hole and expand it so it is not flopping around. Seems to work out fine and yes I have learned all the cuss words and got the scars to match.
I tend to agree with Old Magnet on this comment, if I was to use split pins I would only use genuine pins OR nice fat hardened pins with no play in the holes! (not to pins you will get from your local bolt shop that are made from butter)
I was told by a man that should have known, that the split lock washers not only did not prevent loosening as well as proper torque and a thread lock material, OR a self locking nut, be it nylock or crimped metal, but in testing was always the failure point in high strength fastener testing. No matter how good you make them, they always fail first due to the fact that they're not a solid ring. The split lock washer was part of the world of World War One, where most of the bolts were barely better than mild steel and had square heads. I still use them on grade five bolts if its somebody's garden tractor or utility trailer, anything where it's a critical fastening point, or I'm building it for sale, I used nylocks, or on blind threaded holes, Loctite. As to the split pin issue, just as Tony sez, if there's a place for them, I put them in, more to give it an authentic look than anything, or to avoid some old-timer from saying I was lazy and left them out!
My biggest peeve with split washers is the seats they destroy during that first turn or so on removal. I'm a big fan of deformed flanged type locknuts or the grade "C" regular deformed lock nuts.
In my first or second year as an Apprentice I had to assemble some new implements something I had done many times before, only this time in the kit of fasteners was something that had not been seen or come across by anyone in the shop the Nylock Nut, the result being that after some debate I was told to fit the nuts upside down being told the white plastic bit was in place of the spring washer? as luck goes that week I had a trip with the Co's Truck Driver to help collect a new large implement, on it I spotted these new Nylock Nuts fitted correctly, resulting in myself making a Bee line to the implement when back in the Yard to correct this nut thing, only to find that the implement had been collected never to be seen again. tctractors
LOL, Don't be cheeky it can get cold here in QLD, not so much near the coast but it can get below 0c in the inland areas, but winter is not long in these parts thank goodness, roll on summer, cold beers beside the pool. LOL