Serial 1JD03327 I'm doing a possible pre purchase look at this machine for a client. Looks like all of the undercarriage is relatively new. But then this... any ideas? worn out major bogie pin or worn out bore?
Major bogie pivot definitely. Whether it is pin or bore is somewhat irrelevant at this point. Needs fixing and because of the tooling involved won't be cheap.
Do you suppose the pad is bad between bogie and frame is bad and the trunnion looks suspect
It might be worthwhile to get the tractor jacked up and take a look underneath. It would be interesting to see which way the rear major bogie moves when the tractor lifts.
I don't think its the pad. In my mind the geometry doesn't work. I actually don't know what you mean by "trunion". I am 90% sure that it is the major bogie pin (I always say that wrong, I think they are actually called bogie cartridges) as well as all 32 minor bogie pins. But I won't know until I can break the track and actually be able to manipulate it.
look at blade trunnion (what the push arm connects to) also look at how high the rollers are on the rails
I was thinking about that. But I kind of thought that if I did try to use the ripper and blade to get the dozer off the ground the weight of the track would make it near impossible to move the bogie. Also, it looks like the belt tensioner bearings or bushings are worn out. Very odd wear on the belts. Actually, the first thing I noticed was that the belts had jumped grooves on the dampener. And one was just dangling in the breeze on the fan shaft. I put them back where they should be and the dangling belt became tight, but the other two were loose. I have a theory about that. I can see an a/c receiver dryer, but no a/c compressor. I am kind of thinking that one of the three grooves used to be the Ac belt and it has been gone so long that the other grooves have worn. So I am not even going to start it until I can get new belts.
We had a lot of those size frames upside down at Finning Mildred Lake in Fort McMurray, and those size pins are definitely alot to press out, not including how much bore got worn out. Big rams and some sled hammer for extra some times. Simon C
It is a fairly small community here when it comes to cat dozers sized from 8 to11. So I actually know a bit of this ones history, even though this is the first time I have seen it. The current owner bought it from the previous one after it "fell" off a low boy. I don't really understand how that would be a reason to sell a dozer, they are made pretty stout. I just mention it because I cannot convince myself that perhaps it might have something to do with the rear major bogie problem. Also, I know the operator that used to run the machine for the current owner. And gave me the skinny on the machine. All new undercarriage, (I will never understand why people will blatantly say "all new undercarriage" when they mean new chains, grousers, rollers, idler and sprocket segments. But not bogie cartridges. Apparently it also comes with a containers worth of undercarriage parts. They aren't cat parts, some sort of aftermarket. I personally think that cat oem parts are worth the price because they outlast and out perform the cheapos. But it is comforting to know that it comes with so many spares for emergencies. He also told me that the ripper hydraulic circuit was occasionally a little weak. I am thinking that is a load sense problem, but I need to start it test that idea. Honestly, this machine is so old that I need to do a little research to find out if that makes sense. Also, he thinks that sometimes the turbo isn't working. And on top of all of the other problems that I have already listed are multiple exhaust leaks. The stack has holes where it comes out of the engine cover, the elbow that connects to the muffler is toast like there is no flange for about 75% of it. And apparently that exhaust elbow costs $1100. Also, the "slip joints" below that elbow also leak. Before I wrap this up. If I was a mechanic/bird watcher; this one would go in my bird book. This is the first time that I have seen a cat 3408 in person. I think they phased them out in the eighties. Was there something wrong with the cat v8? I am actually pretty excited to hear how it sounds when I replace the belts. It might just be me, but I have always preferred a v8 over a straight 6. This machine is currently priced at 50k and honestly I think that is actually fair. But I bet that my client could get it for as low as 40k maybe even 35k. Let me know what you think
You can see two rollers running against each other in the photo. I think you are right about the cartridges but there likely are problems with the rubber springs the bogies ride against. The frame is going to have to come off to find all the problems. Your are right on about the total undercarriage statement. I've heard PSSRs tell customers a total undercarriage for D9 costs around $85 to $90K from the dealer and never mention the cartridges. Plenty of hard feeling when the total bill ends up at $120,000. I never liked the 3408 engines. Plenty of problems like rear main seals leaking and problems with injection pumps and just the sound of them make me think something expensive was about to happen. They seemed to work good in the loaders. I had then in haul trucks and hated them. Cat apparently didn't like them much either as I don't see them anymore. All big sixes in everything.
I wonder what tracking the machine back and forth might show, especially with a bit of power applied and hard on/off the brakes.?
Me personally don't like any 3400 anything, I remember lots of lifter bore issues.
I thought certain 3406's were really well regarded.
The undercarriage is a Korean DCR/DCF brand.I have used those brands on D9T’s in the past. They are cheap,but ok in certain applications such as low impact material.They can offer decent value for money on a cost per hour basis. However,I would not want them on a high impact rock ripping tractor. It’s an old D9N at $50k (possibly cheaper). It’s a good price for a D9 that’s in some form or working order whichever way you look at it. Yes,those bogies and trunnions are looking horrible and expensive regardless of using non oem parts or not. I’m sure at that age,it will likely be getting used nice and steady in a gravel pit or something. Assuming $50k in parts and labour to tackle those travkframes and pivot shaft/eq bar issues you then own a $100 D9N that will work pretty well. Repairs don’t need to be perfect for that type of job
I quite like the ITR brand of undercarriage and bogie cartridges etc. They offer very good value. Finnings UK have wildly differing pricing of their undercarriages depending on what mood you’re in.
As for the 3408 motors,I love the sound of them but have allways chosen the straight 6 options in all my D8/D9 engines. I’ve no experience in owning V8 Cat powered kit.
Is it much cheaper to maintain or rebuild a straight 6 engine than a V8 over the life of a machine? I think an old analogy was $2000/cylinder for a rebuild. That's $4000 right off the bat and then there's injectors and other extra components on a V8. Have heard 6's run smoother but not sure if they last longer or save a lot of money in the long run? Thinking it could affect a buying decision.
Haven't made it back to the machine. Didn't get belts until this afternoon. So tomorrow I will be back on it; figuring out how to seal up the exhaust leaks to keep the operator alive, testing the ripper, etc. They have been using it for about a month or so and this is the first time that I have even had to look at it. So it must be mostly functional. And on Wednesday it is headed to a new job site. So I have a bit of time to decide if I can recommend it. I think I am still waiting on quotes for the bogie cartridges. I will update you tomorrow.
Those manifold gaskets and any broken studs are a pain on the 3408’s so I’m told. I’m sure you’ll have plenty of experience on broken studs though
They were updated a couple of times with longer studs and spacers which reduced stud breakage but never completely eradicated it.
The broken studs could be the reason the operator said the turbo wasn't working