bostonpowercat
Member
Bostonpowercat.com latest restoration project! Here is a link to the video...http://bostonpowercat.com/blog/caterpillar-dd9
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Caterpillar DD9G/Quad Trac
- Thread starter bostonpowercat
- Start date
tctractors
Senior Member
The tractors look Smokin also the intro is a good bit of camera action, now all that is left is to fit swamp plates to counter all this rain we are getting.
Its taken a few weeks to get it sorted but its been fun, tctractors
p.s. for those that don't know this little set up is in the U.K. and will be used to push load the Scraper fleet, there was talk of using 9 CAT D2's but its easier to use 2 X D9's and 1 pilot.
Its taken a few weeks to get it sorted but its been fun, tctractors
p.s. for those that don't know this little set up is in the U.K. and will be used to push load the Scraper fleet, there was talk of using 9 CAT D2's but its easier to use 2 X D9's and 1 pilot.
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bostonpowercat
Member
RonG
Charter Member
What a tease!!I wondered what you had been up to Tony,I have not seen any posts from you lately,I knew it was going to be good.I don't remember seeing the DD9 working,the vids have got to sound good.Guess I have to keep watching,thanks.Ron G
tctractors
Senior Member
This little chariot is really all Karls efforts with the task going on possibly 10 years, time races on when you have to locate parts on a Global scale, the front nose group on the rear tractor was a bit of work for myself and Karl, we drove for hours then worked for hours then drove home for hours, it was 1 of those days that stay in the mind some, but credit to Karl he is getting good on the spanners now, he also does all the shot blasting and spray painting using paint by the Barrel not the Gallon.
tctractors
p.s. we can Haul this outfit in the U.K. in 1 lump on our roads, it makes all that Faffing about in the U.S. look silly.
tctractors
p.s. we can Haul this outfit in the U.K. in 1 lump on our roads, it makes all that Faffing about in the U.S. look silly.
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kshansen
Senior Member
- Joined
- Mar 11, 2012
- Messages
- 11,162
- Location
- Central New York, USA
- Occupation
- Retired Mechanic in Stone Quarry
A single D9H we have to remove the blade from the front, unless you do all kinds of special tricks, at least that's what I've been told in New York.
I'd just hate to be rounding a curve on my motorcycle and see that load heading my way!
Did you ever see the DD9G they had at the Cat museum at Brooks? (Antique Powerland)
Don't know where it came from, but it looked to be in pretty good condition. I didn't see it last year, so it may be gone. Or I walked right past it and missed it?
Contractor
Active Member
How effective was the DD9G? And could you replicate it with the (2) D7Gs for a 400HP push cat?
d9gdon
Senior Member
No, the DD9G was two D9G's attached with a weight transferring hitch setup. It had 770 hp together, so a lot more power to push those 666 scrapers. They were 54 cubic yard machines, so lots of push was needed.
Here's a real pusher in action:
That's back when they were made to last.
Okay for it's day, ONE operator,bit awkward, shorter service life > finals, steering clutches-brakes, bevel gear shaft etc compared to high drives.
WHY? D8L or D9N,R,T give you very close (379Hp with Tier1 3408E) to over 400Hp (405Hp)
Contractor
Active Member
The why is based on cost of capital. A new D8T is 700K or $12,400 per month at 2.9% for 60. I bet you could put a pair of low hour D7Gs with the hitch for 125k or 2,400 per month for 5.5% for 60. Fuel is close, labor is equal, maintenance is higher but manageable.
I've worked on DD9Gs, maintenance compared to high-drive is more than doubled. D7Gs end of production was 1987; 31-32 years ago. Low hours?
Trunnion Ball - Hitch D7G-D7G would have to custom fab'd and Front-to-Rear engine-transmission controls. DD9G used air controls; you would have to fabricate air cylinders to operate the steering-brake combo and engine governor controls (decelerator).
Another consideration is emissions regulations; Texas has their own with limits per zones.
New 8T; I would look for a 9N-R in good shape, plenty of push power for 621 scrapers. Cat performance handbook matches up 621s with 8T.
8T pushing mismatch, but economical for the situation.
Job located close to my place.