Author Topic: Who has traveled through the Black Hills and the Rockies with an 8v71 MCI 9 ?  (Read 5727 times)

Offline RickB

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Alright here's the deal. The family and I are planning a trip from Minneapolis to Rapid City continuing on to Carbondale Colorado. As I sit here looking at my map it shows hills starting out side of Sioux Falls and anyone out there with a 40 footer with an 8v71 towing a car knows that hills are an issue, especially in the summer. With the bus air on and the car hooked up on a 90 degree day the warmest my motor has ever been is around 190-195. I am not concerned with time but engine temp and I am wondering what to expect once I clear Denver and start the 75 mile of pure terror Rockies. I have Jakes and I plan on going either early in the morning or late at night to fight the afternoon temps. One adavantage I do have is an Allison 754 5 speed transmission.I have avoided these areas to this point with both my buses but I have to figure that there were alot of 8v71's climbing them in the 70's and 80's. If you have made the trek I would appreciate some advice. Would you do it again? Did you regret doing it? Was it harder, slower or hotter then you expected? The thin air, 20 mile 7% grades and no service areas are making me nervous and I need my faithful bus friends to chime in. Be kind with your responses I am simply asking for advice. Also I plan on unhooking the car after Denver and through any parts of the Black Hills where it seems that unhooking would be safer for my family. Thanks in advance for your time and advice. Rick Barron
I will drive my Detroit hard... I will drive my Detroit hard.

Offline tekebird

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Rick, I've done the Rockies with my 4104 (6-71/4 speed manual) towing my F150 supercab long bed twice.

providing your engine and trans are working well and your cooling system is up to snuff.
no worries

Offline TomC

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Climbing the hills isn't the problem-it is having to start on a 6-8% grade in altitude that might get you.  I would suggest you find a 8% grade and with your towed attached try starting from a dead stop.  If you have an automatic, probably OK.  If you have just a 4 spd-well give it a try.  You should also have Jake brakes on especially in Colorado.  Good Luck, TomC
Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline tekebird

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on the route intended there should be no reason to need to start on any grade. providing you intend i=on taking 70 up to Glenwood springs.

also, providing you don;t intend on going mountain driving on two lane roads, probably don;t need the jake either although it might be nice.


Offline RickB

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I do have jakes. I am unhooking the car before the mountains and I have an automatic 754 Allison. So all three things should not be an issue. We do plan on I-70 to Glenwood Springs so no "off-roading". My Allison is a 2nd gear start but I can shift it into 1rst manually. That granny gear has some torque! I am feeling more and more comfortable with the thought of this. We already took this bus over Monteagle pass outside of Chattanooga in the middle of an 80 degree day. She performed flawlessly. Thats a 6 mile 7% grade coming from the south.
I still am open to suggestions from all you mountain climbers out there.
I will drive my Detroit hard... I will drive my Detroit hard.

Offline TomC

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So what you have is the Allison HT750DR.  I wouldn't worry about climbing any hill with that set up-just watch your temp gauge (you do have an transmission temp gauge?)  Good Luck, TomC
Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline Hi yo silver

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Rick,
Good topic!  I'm following the responses closely because I have a similar setup, only with a 754 tranny.  Only two or three trips with my first bus, an MC9.  So far, so good, towing a full size pickup on a 95 degree day in gentle hills.  No long climbs. 

I have thought if I ever had a heating problem and had to cool it down in an "emergency", I could always spray the radiators with a hose I have connected to the fresh water tank. (Any comments here?)

As far as the capability to start on a steep incline, seems to me like a reasonable concern, since you could always be forced to stop by a traffic tie-up or an overheated DD.
Blue Ridge Mountains of VA   Hi Yo Silver! MC9 Gone, not forgotten

Offline Beatenbo

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I took my C3 6V92T over I-70 to Grand Junction and with a 14,000 elevation this was the first time my engine ever heated up going up to the IKE tunnel. I have the large radiators and I never see over 190 degrees on a 90+ day. I am crossing in about 3 weeks in hot August and I plan on crossing at night. Last time coming back sprinkle rain at night and never went past 170. Rockies are brutal on a 2 stroker. I said the next time I would leave my bus in Denver and rent a car, but looks like I will do it again soon.

Offline gumpy

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I've done those routes in my MC9, but I have a 6V92 with larger radiators. I've had heating problems, but typically only across NE or SD, not in the mountains, and I can usually control it simply by slowing down some. I don't think you'd need to unhook the car in Denver, but you should learn to downshift manually to keep your RPMs up.

So, are you in Minneapolis?

craig
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Located in Minnesquito

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Offline Devin & Amy

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Rick,

I drove over the Bighorns , the Rockies at Jackson Hole, and drove back through the rockies of Montana, all from Northern MN.
I have an old 8v71 with the 4-spd.
You will be going pretty slow up and probably even slower going down, but the bus will pull it. I had a lot of smoke at higher elevations.
The gutcheck comes when you are climbing a 10% grade in first and you feel her RPM's dropping out. :o
Devin

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Happily Bussin'!!

Offline larryh

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I drove my 40 ft Buffalo with 8V71 and four speed 7000 throught black hillm sand through Mt Rushmore etc to Upper MI and back through Denver I did hit 200 a couple of times and that summer was some of the hottest days ever 110 at Rushmore All I can say is use your gears and enjoy the ride and take your time.

Larry Higuera

Quartzsite AZ currently In OR.
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A cowboy's only afraid of two things:
havin' ta walk,
and the love of a good woman.
"This posting was generated using an environmentally friendly, self contained flatulence generator, therefore no fossils or neutrons were harmed in the creation of this posting.


Quartzsite,

Offline gumpy

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The gutcheck comes when you are climbing a 10% grade in first and you feel her RPM's dropping out. :o

He should not have that gut-check feeling with his 754 tranny.  I have had to drop to 1st gear a couple times in CO and on the trip to AK. The first time I had to do it, I was very nervous because I didn't know what was going to happen, and had visions of continuing to  lose power and coming to a stop on the hill. To my relief, when I hit 1st, it powered up and actually started to increase speed. The engine
came up to full RPMs and the temp never budged. Keeping the RPMs up keeps the fans turning to pull max air through the radiators
and keep it cool. My bus weighs in at about 34K and I was pulling the Explorer.

Craig Shepard
Located in Minnesquito

http://bus.gumpydog.com - "Some Assembly Required"

Offline rip

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I have an 8v92 with a 748 Allison weighting 39,000 lbs.pulling a Tacoma.I was pulling Wolf Creek Pass in Co. last week and that is the first time I overheated. I am currently in Steamboat Springs and I'm leaving this morning with a 8 mile pull to get out of here.I'm taking my toad off and I hope that will help.I'm headed to Rapid City but will go around the Black Hills.I have run the hills before with no problems. I find the hardest pulls in Co.I do have Jakes and I don't think I would run mountains without them.
Don


Offline edroelle

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10 years ago, I did do that run with my 8V71, big injectors (smoke) and timing not advanced, no Jake, 740 Allison, MCI 8, brand new radiators, pulling a Buick LeSabre on a dolly.  Probably about 3600 pounds.  Ambients were up to 107 degrees.

Overheating did occur often when I tried to pull hills in 2nd or third gear.  I had to stop on the shoulder numerous times to fast idle and cool down. I could take any mountain in 1st gear, WOT, 19 MPH, with no problem.   But, until I learned that, I was very nervous going into the mountains.

Sioux Falls to Rapid City is basically flat, so no problems.   Most roads in the Black Hills and Yellowstone were no problem with the toad.   I did have to unhook the dolly one time in Custer State Park because of a switchback in the road.  That was a hassle.

After that trip, I knew I needed a jake and wanted a turbo engine.

I thought I would move faster and run cooler.  With new radiators, I was surprised I had a problem.   I had the smaller radiator fans, but a small upper pulley.  I think the fans increased in size in about 1982.

It was a great trip, but just expect to drive slower to stay cool.  Make sure you radiators are clean and in good condition.  Also, check that the radiator has a good seal to the body, and that the fan door has a good seal.  That will allow the fans to pull air only through the radiator.  If you have rotted radiators, I would have a concern.

Ed Roelle
Flint, MI

Offline rusty

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Rick    Sounds like you have it figured out. Unhook your toad, drive early in the morning and your bus is in good shape you will have no problem. You will have three pulls to look forward to. First Floyd hill just west of Denver about 7 or 8 miles of steady pull. Then Georgetown to the tunnel. Just west of Georgetown is about 2 miles of hard pull then stead pull of about 10 miles to tunnel. (11,000 ft.) Out of the tunnel you go down to Dillon about 6 miles. My rule is you go down slower than you go up ( one gear lower ) After Dillon a few small grade changes to Copper Mountain. Then Vail pass approx 12 miles of steady pull to 10,700 ft. than approx 12 miles down to Vail.. PLease take your eyes off the temp Gauge long enough to enjoy the scenery. I live about 35 miles north of Denver. I have a place to stay over night with water and electric. Your welcome to stop by if you do not  mind parking next to a rusty Eagle.   Good Luck Wayne