being they were the first series of high drives, what are the weak points to the d8l? thks
I'd like to know also. Just bought one, with a universal blade. 28" pads
Heavy old horse's would be one.
It's a D9 in disguise. Here's a nifty graphic i found elsewhere on HEF.
As pointed out above, remember that although the badge says "D8" it would pretty much line up alongside today's D9 in size/horsepower. Lift cylinder can give problems leaking from the rod seals. Try to keep all fluids as clean as possible, especially hydraulics. Maybe even put lower micron-rated filters in to keep things cleaner. Use the narrowest track shoes you can get away with to maintain flotation, otherwise everything else in the undercarriage suffers. Unless your in really soft ground all the time there's no need for much more than 24" shoes IMO. Shows my age but I remember the L replacing the D8K. We were very sceptical at the time of the increased height/weight, etc, but the new model was such a quantum leap forward that after a couple of years we couldn't imagine going back to conventional tractors.
was the D9L not the first hi rise dozer made
No. That was the D10, now the D11T. 1977 or thereabouts. D348 engine., Who remembers those fondly ..?
yes i am getting a bit mixed up ,the D9L was the first hi rise to make it to the UK ,i can remember going to see it on its first job with my Dad it was owned by Blackwells cheers graham
I remember Stokeys getting their first elevated sprocket cat tractor. Operators who'd cut their teeth on D9G & D9H tractors didn't know what to make of the D9L. It ripped well though, much better than conventional tractors.
did they rate these different then the other high drive d8's then, im getting a spec of about 83k on websites, is this underrated or is that about what they weigh, cause it says a 8n and r also weigh 83k? also is the 83k that im getting, is this with a blade and tractor, or how are these spec'd? thks
All were about the same weight, but HP on later models went down. D8L 83k/335 BHP (up to 400 BHP for special applications), D8N 82k/285 BHP, D8R 84k/310 BHP. The weight you're being quoted should include a blade but not a ripper if one is fitted to the tractor. #8 Semi Universal blade should weight around 10.5k #8 Universal blade should weigh around 12k. Both weights include blade, push arms, cylinders & mountings, lines, trunnions, etc. Ripper frames (both single & multi-shank) will weight about 9k plus about 1k for every shank fitted to them. The current D9T (410 BHP) that is about the same physical size as a D8L goes about 105k with a single shank ripper & SU blade, so approximately 12k heavier than the D8L of almost 30 years ago that spawned it ...........
thanks guys, they had good luck with the suspended undercarrage and 3408?
Suspended undercarriage won't give you problem so long as the rubber pads are kept in good condition and replaced immediately when they split. Look for signs of crack repairs on the track frames and the bogies, that's a dead give-away. Also any leaks in bogie pivot pins need to be attended PDQ or they will seize and you can't get the pins out. 3408 is a 3408. Not the greatest engine in the world but reliable enough if it's maintained properly. Thank your lucky stars it's not a HEUI.
I believe they were not so good had them in Cat 779 Electric truck( yes electric trucks) in the mid 60's the engine wouldn't breath valves to small and turbos weak.
We had them in first generation 777 trucks (84A prefix) in the late 70's. Mechanics got really good at rolling crankshaft bearing shells in them. The Achilles heel of the bottom end was actually the oil pump, we used to change them at half engine life to maintain oil pressure. The DOHC system was more suited to a racing engine rather than an industrial engine IMO. When I had a 2nd go-round with 777's in the early 80's we were lucky and had a downhill loaded haul, so we had the engines derated from 870HP to 800, then finally to 750. At 750 BHP the engine would live, at 870 it most definitely wouldn't.
3408 shouldn't have been around until the 70's and it's not dohc. The 1693 was dohc but not a v motor, I believe the early v-8 was a 1678 but im not sure. Cranks can be a problem in the 08, at least in trucks. Sent from my DROIDX using Tapatalk
We didn't have much lower end problems as we did with the cylinder heads the exhaust valve ports would carbon up and the valves would hang open and of course burn, the truck was so compact it was easier to pull the engine than change the heads in truck, we dropped from the bottom like the old VW,s. (Arizona no A/C)
Sorry didn't see the d348 conversation and it wont let me edit this, carry on. Sent from my DROIDX using Tapatalk
The past few years, I've been using a D8K for road building and pit development. This May, my boss said he needed it's stump splitter for some of his jobs, and I would have to take the D8L for mine. I was a little disappointed since the first L I had ran always was over heating it's tranny. It didn't perform as well as the K. It had the single shank ripper and evidently the lower HP motor. We bought another from so cal. and the first went to auction at the recession. The new one had the double shank ripper and 22in pads. First push, I knew this one was different. Wow! This thread explains alot. Anyway, what I've noticed the past few months is: A misconception on my part- Elevated sprocket stays out of the dirt. Turning around fast in deep loose dirt, seems to let the rails carry the dirt up to the sprocket where it packs and if the tracks are a little loose, the rails can catch the edges of the sprocket teeth. Track tension is very important. Keep the tracks fairly tight. Don't let them rub on the track frames behind the front idlers. Also, in the track frame along with the track adjuster, is the oil reservoir for the recoil ram. Keep this level up. Dipstick is part of the 4 bolt cover. Just found theservice book for it at the shop last Wednesday, so between it and this forum I'll get to know it better. Blade has a tag- 9W800.
well he already mentioned it ^^ but keeping the transmissions cool, ive been around a few of them, some guys blocked 3rd gear out to try to keep heat down. of course how your using it and outside temp factors into all that. the 3408 in a dozer sucks bad if your having to do lower engine work in the chassis, you can hardly even get the oil pan off in the chassis, and if you can get it off, you still cant see what your doing under the 5-6 cyls