Bus Conversions dot Com Bulletin Board
December 19, 2014, 07:02:55 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: If you had an Online Subscription: By clicking on any ad, a hotlink takes you directly to the advertiser’s website.
   Home   Help Forum Rules Search Calendar Login Register BCM Home Page Contact BCM  
Pages: [1]   Go Down
  Print  
Author Topic: Jack size?  (Read 1287 times)
steve5B
Sr. Member
****
Offline Offline

Posts: 272





Ignore
« on: September 06, 2009, 12:25:24 PM »



   Wondering what size  jack does it take to raise the front end of my bus, MC-5B.


   Thanks,

  Steve 5B....
Logged

WWW.WINNERSCHOICECORPORATION.COM

"It's all in the name the name says it all"
Don4107
Sr. Member
****
Offline Offline

Posts: 407





Ignore
« Reply #1 on: September 06, 2009, 01:43:18 PM »

A 5 ton would be too close to rated lift for me if you are trying to raise the whole thing in one stroke.   A 10 ton would be about 50% and a 20 ton about 25%. I would not put a jack in the middle of the axle.  Instead raise one side at a time.  If buying a jack get one that will work for the rear too.  I would go 20 ton.  Do you know where the jack points are for you rig and how tall the jack can be to fit in there even with a flat tire?  Run up blocks can save the day.

You did not say how high you need it or what you are working on. When I had to raise the front to change a radius rod mount, I drove it up on blocks.  Jacked that wheel just enough to remove the weight from the tire after breaking the lugs loose and blocked the axle at that end.  Being up on the blocks gave me plenty of room to work even with the suspension aired down.

Always assume the suspension can/will drop and be safe.  The surface you are working on also has to be capable of supporting the jack.  If not use something to spread the force over at least the footprint of a tire/tires and to keep the jack from tipping.

Don 4107
Logged

Don 4107 Eastern Washington
1975 MCI 5B
1966 GM PD 4107 for sale
1968 GMC Carpenter
NJT 5573
Hero Member
*****
Offline Offline

Posts: 808




Ignore
« Reply #2 on: September 06, 2009, 01:55:27 PM »

Steve,

A 6 ton will probably do it. 5 ton rated 10,000lbs, 6 ton rated 12,000 lbs etc.

If you are going to use a center point on the bus though, and jack the entire front at once, get some extra capacity.

I don't like to carry more jack around than I have to so I use 2 6 tons for about everything.

I have known old time shop mechanics though that had 50+ pound 20+ ton jacks that they thought were just fine for all shop work. I just don't like lugging them around and positioning something that heavy all the time. They may be a little safer though.

The screw adjustments in the tops are soft on the chinese brands, so if you buy a cheap one you should get extra capacity or not screw the head out very far when you use the jack.

I am a complete nut about collecting wood blocks that I use for safety blocks and all kinds of other things, so you may want to start a collection like that for yourself too if you have room. My wood block collection is second to none, and I use them alot, I had to get the back of my Eagle about 4 feet in the air to remove the muffler, but it didn't make a dent in the block pile!
Logged

"Ammo Warrior" Keepers Of The Peace, Creators Of Destruction.
Gold is the money of Kings, Silver is the money of Gentlemen, Barter is the money of Peasants, Debt is the money of Slaves.

$1M in $1000 bills = 8 inches high.
$1B in $1000 bills = 800 feet high.
$1T in $1000 bills = 142 miles high
zubzub
Hero Member
*****
Offline Offline

Posts: 1168


'53 4104. Roadworthy but rough around the edges.


WWW

Ignore
« Reply #3 on: September 06, 2009, 02:29:41 PM »

I have a 12 ton  air over jack that I use, I also have a 10 ton, I hardly use the 10.  The nice thing about the air over is that you can lift without being under/near under the bus. I have done most of my work on gravel, so I never trust my jacks even when they have steel plates under them.  I jack as jack as high as I can go, install cribbing, if I need more height I repeat. 

I trust the jack just not the ground (asphalt as well) so I always use soem kind of cribbing. 

I like the extra power of the 12 ton, if you aren't familiar with the weight of a lift it is easier to judge it on a jack that is not maxed out and is not lifting near the edge of it's ability.
Logged

JohnEd
Hero Member
*****
Offline Offline

Posts: 4571




Ignore
« Reply #4 on: September 06, 2009, 04:03:56 PM »

Harbor Freight air over hydraulic 20 ton and it goes for less than $100.  Like Zub said, don't need to be under while jacking.

John
Logged

"An uneducated vote is a treasonous act more damaging than any treachery of the battlefield.
The price of apathy towards public affairs is to be ruled by evil men." Plato
“We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.”
—Pla
Ed Hackenbruch
Hero Member
*****
Offline Offline

Posts: 2478




Ignore
« Reply #5 on: September 06, 2009, 06:13:44 PM »

I also got the 20 ton air over hyd. jacks at Harbor Freight on sale for $64 each and love them.  Have a couple of other 10 & 20 ton hyd. jacks for backup but never use them anymore. Smiley  Don't know about your 5C but on my 5A you can only jack it up using the 4 jacking points......anywhere else will cause damage.
Logged

1968 MCI 5A with 8V71 and Allison MT644 transmission.  Western USA
Melbo
Hero Member
*****
Offline Offline

Posts: 1076


MC8 under construction




Ignore
« Reply #6 on: September 06, 2009, 06:18:52 PM »

I too use the air over from harbor freight

I also have a plain 20 ton -- I'm probably too old for moving those heavy jacks around but do it any way

I like over kill in situations like this --- Lots of blocking is a VERY good idea

HTH YMMV

Melbo
Logged

If it won't go FORCE it ---- if it breaks it needed to be replaced anyway
Albuquerque, NM   MC8 L10 Cummins ZF
Hartley
Hero Member
*****
Offline Offline

Posts: 1217





Ignore
« Reply #7 on: September 06, 2009, 07:01:57 PM »

Hi Guys,

I will only comment on something else that was said that may be confusing to others.

Always use the "FACTORY" jacking points on ANY bus. There are NO other places to put a jack to lift with. ( Unless you have full wheel lifts or ramps. )

You should always use 2-Jacks to lift the end of any bus. One on each side.
Never on an axle (front) or strut or on any point that wasn't designed to be jacked on. ( If you are just doing tires the 20-50 ton rolling service jack should work OK for lifting an axle if you are careful what you lift on. )

So If you want the front lifted to work on it, Use 2 jacks. You can optionally only lift each side if just changing tires and stuff.

On the rear axle you can jack on the axle itself if you stay on or near the u-bolts or mounting stansions on the axle ( as close to the end as possible ).

As for the Capacity. No less than a 12 ton jack. That will be just barely enough to work on the heavy ends of a bus. Better to Insure safety with a 20 Ton minimum. You may have a space issue to get some of the 20 ton's into the right place. You could use a 12 ton to do the first lift for clearance and block things up so you can place the 20 in there.

Run to Lowes and get plenty of 4X4 PT and/or 6X6 PT lumber to make cribbing.

Be safe....
Logged

Never take a knife to a gunfight!
paul102a3
Full Member
***
Offline Offline

Posts: 191




Ignore
« Reply #8 on: September 07, 2009, 04:07:11 AM »

My parts book for a 102a3 shows a 12 ton jack as standard equipment. The book does not give part numbers but does specify a Blackhawk brand name .

I purchased a manual 12 ton from Northern Tools but found it hard to use laying under the bus.  I now have a second jack which is a 12 ton air over hydraulic and it is real nice.

The one downside I have experienced with the air over hydraulic jack is the tight fit between the front tire and factory jacking point on the drivers side. In order for me to have access to the release valve of the jack, I have to position the jack right up against the tire so the screw head of the jack will seat into the jacking point on the axle.

While I would prefer a 20 ton air over hydraulic model, there is no way the ones I looked at would work on some of the jacking points a 102a3 due to the extra width of the jack.

Paul



 
Logged

2001 Prevost XL II
buswarrior
Hero Member
*****
Offline Offline

Posts: 3571


'75 MC8 8V71 HT740




Ignore
« Reply #9 on: September 07, 2009, 07:17:04 AM »

I will re-enforce the comment about jack height.

Measure the clearance under your jacking points.

There are many nice jacks out there that will not fit under the jacking points when you need it.

There is great danger being on the side of the road, and the faster you can get your business done and out of there, the better. A single run-up block to get a shorty jack under a flat tire is hard to have to do twice.

Just for fun, did we stash the rarely used jack and related paraphernalia on the "street side", next to passing traffic, so we have more space for the gear we use more often on the "camping side"?

happy coaching!
buswarrior



Logged

Frozen North, Greater Toronto Area
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!