What Makes A Tractor "hop" When Starting:

[Rob]

I hitched up last night to the trailer for the first time. Had a hell of a time cause it don't have no spring brakes, the service brakes do not seem to work, and I hadn't blocked the tires: Anyways, I've noticed when I let the clutch out in 1st gear, (second to me) the trailer causes the truck to "buck" or torque up until it gets rolling. It did this a couple of times and when I place the trans is low gear, (1st to me) the truck starts off really easy but runs out of gear shortly afterward. All the bushings are tight meaning transmission bisquits, engine isolators, torque links, trunion, and saddles for the springs.

Once you get rolling, the upshift is very smooth. I haven't been far enough to test downshifting yet. I then went back to my property, was attempting to turn around in the dark, and while performing the swing got the trailer tandems dropped into a depression with the tractor sitting on "glare ice". In other words, everything stopped right there. I can't go forward, or backward, so there she sits in the back yard. Of couse not having my other winch truck, (Fred the crane) running for over a year, he won't start. I then called Jamie in from home, dug ole "Fred" out of his own ice chest he was buried in, and pushed him inside the shop to warm up. There has got to be a valve under the trailer either stuck, or frozen as there are absolutely no working brakes whatsoever.

Going back to the shop shortly. Will get "Fred" up and ready to perform, (as usual), winch the tractor and trailer back onto a grippable service and pick up where I left off.......

Rob

[other dog]

I hitched up last night to the trailer for the first time. Had a hell of a time cause it don't have no spring brakes, the service brakes do not seem to work, and I hadn't blocked the tires: Anyways, I've noticed when I let the clutch out in 1st gear, (second to me) the trailer causes the truck to "buck" or torque up until it gets rolling. It did this a couple of times and when I place the trans is low gear, (1st to me) the truck starts off really easy but runs out of gear shortly afterward. All the bushings are tight meaning transmission bisquits, engine isolators, torque links, trunion, and saddles for the springs.

Once you get rolling, the upshift is very smooth. I haven't been far enough to test downshifting yet. I then went back to my property, was attempting to turn around in the dark, and while performing the swing got the trailer tandems dropped into a depression with the tractor sitting on "glare ice". In other words, everything stopped right there. I can't go forward, or backward, so there she sits in the back yard. Of couse not having my other winch truck, (Fred the crane) running for over a year, he won't start. I then called Jamie in from home, dug ole "Fred" out of his own ice chest he was buried in, and pushed him inside the shop to warm up. There has got to be a valve under the trailer either stuck, or frozen as there are absolutely no working brakes whatsoever.

Going back to the shop shortly. Will get "Fred" up and ready to perform, (as usual), winch the tractor and trailer back onto a grippable service and pick up where I left off.......

Rob

Probably the just type of clutch. I drove a cabover KW with the ceramic clutch disc and it would shake the cab starting off loaded. When the wheels started turning you just had to let off it and go,couldn't slip it much and ease off it or you'd get a whole lot of cab shaking going on.

Or, much like a 5 speed Mack,you can take off in low and soon as the wheels turn you can shift to the next gear.

[hatcity]

In-experienced driver.

Some day said driver may find drive shaft in a pretzel like configuration.

[gearbox]

Wonder if S-Cams are siezed? service brakes as well as spring brakes not working maybe trailer needs some work

[cgallamore]

to much greese in throwout bearing???????????

it happens

[Rob]

In-experienced driver.

Some day said driver may find drive shaft in a pretzel like configuration.

Naw, really don't think it would be that. I've replaced too many drivelines to punish my own. Actually I've never torn one up, even in a car. This one is not bad, Once I got the clutch used a few times, the hopping stopped. It accelerates fine, just a couple slight hops or "torquing up" when engaging the clutch.

Rob

[Rob]

Wonder if S-Cams are siezed? service brakes as well as spring brakes not working maybe trailer needs some work

The trailer does not have spring brakes. There is a plastic looking valve the air tank feeds and has four hoses attached that run to the service chambers. These hoses do not have any air applied to them so no "S" cam action, or brake application. I don't know if the pilot line is supplying air or not at this point, or the valve is stuck. I got the truck winched out of it's predicament and put it inside the building to warm up.

Rob

[cgallamore]

i have to use low gear in mine or it will hop, with a trailer

[Rob]

i have to use low gear in mine or it will hop, with a trailer

I had never experienced any hop at all without a trailer. It also does not hop at all if starting off in low gear. Also If I let the clutch out slowly in 1st, (second to me) it doesn't hop either. Of course there is no load on the trailer.

Rob

[Rob]

Got it winched out this afternoon by backing ole "Fred" up against a tree to keep from pulling back. The hill was so slick I had to winch up to flat ground as under the snow is plenty of ice. Here also are a few photos of the trailer hooked to the truck. It is all now in the building warming up so I can diagnose the brakes tomorrow.

Rob

[Rob]

One more.

Rob

[RowdyRebel]

Heck, ya might get 'er in the garage and thawed out and everything will be working fine. A little moisture in the system tends to freeze up valves on cold days and make things not want to work.

That's also the easiest kind of repair to make...providing you have an indoor heated facility large enough to fit the truck & trailer, which I'm guessing you probably do.

[Lmackattack]

you will get a hop with a warped clutch. think of it like a warped rotor. if any of the clutch plates are warped just slightly it will try to bounce. if you are in to high of a gear it will do this. Will also get a bounce from wheel slip if the powerdivider is kicked in.

dont feel bad about getting stuck in the snow. its very easy. I got my tractor stuck this morning in its parking spot. Got a whole 3" before it slipped and dug in. had a wheel locked up so that dident help. It took 15 mins of rocking it back and forth to get it off of 2" of snow. Loaded your pretty much good to go but bob tail or empty good luck on any hill if you stop.

[Rob]

Heck, ya might get 'er in the garage and thawed out and everything will be working fine. A little moisture in the system tends to freeze up valves on cold days and make things not want to work.

That's also the easiest kind of repair to make...providing you have an indoor heated facility large enough to fit the truck & trailer, which I'm guessing you probably do.

I'm hoping it will thaw out overnite. The trailer was pulled from Manchester NH on Monday and I received it on Wednesday night. Cold weather all the way. The building is 100ft deep and the truck and trailer are backed up to the front of the brown R700 with an R model cab in back of it. The trailer is 42', and the tractor has about a 220" wheelbase.

It was kinda neat to see black smoke from the stack under acceleration too. Means some heat in the exhaust and will surely clean up the innards of the engine. The fuel in the truck is at least four years old.

Rob

[vision386]

Hey Rob, hate to get off topic,but what is in the background,upper right side of this picture? could'nt make it big enough to see clearly,and my eyes ain't what they used to be!...........Trailer looks to be in pretty good shape by the way!.........Mark

[Rob]

Thanks Mark.

The truck is a 1948 Federal. I really don't know what is going to happen with that one yet.

Rob

[David]

Those pictures gave me flashbacks of some of my father's "What the Hell were you thinking" lectures.

[bullhusk]

Thanks Mark.

The truck is a 1948 Federal. I really don't know what is going to happen with that one yet.

Rob

Rob what da ya mean ya don't know what to do with the Federal??? Ya pull the cab off the frame an do it up real real nice ya see; An then ya pull the Dodge into the shop yank the rusty old cab off an either re do the V10 or drop a 5.9 Cummins in there in front of a 6 speed stick (I'm sure you can find a motor an trans.in a salvage yard) Then get yourself a nice 5th wheel trailer like your friend has an VOILA!!!! I know I know you think I'm crazy right? But I think I might have just planted a seed in that motor head LOL

Ernie

[randyp]

One more.

Rob

Im specting you best be getting you a rain bonnet on top of that air filter mister,,,good pics,,,randyp {thas prolly whats making it bounce}

[Rob]

Im specting you best be getting you a rain bonnet on top of that air filter mister,,,good pics,,,randyp {thas prolly whats making it bounce}

The rain bonnet is on the front seat. I had to take it off cause the truck when stuck was about 250 feet from the shop and needed a shot of ether to get going. It was 2 degrees outside overnight and this thing has a 1500 watt heater on the engine. Too much current to pull through extension cords that far. I don't like to ether engines but it fired right off.

Rob

[Rob]

Those pictures gave me flashbacks of some of my father's "What the Hell were you thinking" lectures.

I wouldn't have received a lecture from my grandpa. Instead he would have pulled up a lawn chair, sat down wearing winter coat, boots, furry hat with pull down ear flaps, and gloves, popped a "Falstaff", and laughed at me!! Oh the fun, (at my expense) he would have had.

Actually there was a very valuable lesson learned here. I've never had a semi trailer and certainly never operated one in the winter, off road. I had no idea how easily this truck "stuck" with the trailer hitched up. I've been over that same area in all four seasons with my trucks and never been stuck once. Oh well, I know what not to do again so I suppose that's positive.

I also did discover about the truck something that displeased me. I think the power divider needs rebuilt. Sometimes it would hold both axles together, but most of the wheel spinning was done only on one axle. It does not have the air interlock but rather the automatic one. Sometimes the truck would spin tires on both axles however. Also was able to figger out where the slight exhaust leak was under the cab. It was so cold outside I could see just a trace of exhaust escaping from a rub hole under the cab. So small I couldn't feel it with my fingers but it would put exhaust into the cab without the floor mat in place. I thought it was the flex pipe from the turbocharger but it looks good. The leak is dead under the cab floor and on top of the fuel tank will little room to run through.

After I got back up on solid ground I went down the road about a mile to see how the truck pulls. To my surprise it is amazingly smooth through the acceleration up to highway speed. I then turned around and headed back to the shop and as I mentioned earlier the smoke was dark gray to black from the stack. I've never seen this truck really smoke under acceleration due to no weight back there. I may drive a truck up on the deck later in the week and go for a cruise.

During the winching I was standing outside of ole "Fred" at all times. Once I got off the clutch to start pulling I just guided the R model around the trees "Momma" planted last spring. They are just sapplings so would flatten easily then that's a whole nuther set of problems! I was always gonna build me a set of scotch blocks for "Fred" but never did and have never had a way to anchor him down under a pull. He is actually a small crane, but does a fine job winching especially when he's all you got for that task available.

I'm going to head out to the shop in about an hour to get a look at the brakes and start pulling the front deck boards off. There was some unknown rust issues in the 5th wheel plate area needing addressed myself and the seller are working out to have rebuilt.

Rob

[Mack Doctor Jr.]

It might be the "Dogs" that hold the center plate? We had that once happen to us. Mostly under a load when taking off.

[RowdyRebel]

I wouldn't have received a lecture from my grandpa. Instead he would have pulled up a lawn chair, sat down wearing winter coat, boots, furry hat with pull down ear flaps, and gloves, popped a "Falstaff", and laughed at me!! Oh the fun, (at my expense) he would have had.

Rob

Your grandpa was a smart man. Have you seen what they call "entertainment" on TV these days? Pathetic, really. If it weren't for Fox News and Nascar, I wouldn't even own a TV.

I'd probably get more done around here though....

Damn Fox News and Nascar! And the interweb too!

[randyp]

The rain bonnet is on the front seat. I had to take it off cause the truck when stuck was about 250 feet from the shop and needed a shot of ether to get going. It was 2 degrees outside overnight and this thing has a 1500 watt heater on the engine. Too much current to pull through extension cords that far. I don't like to ether engines but it fired right off.

Rob

I like to use Silicone Spray Lubricant, stead of ether, it makes them spin faster when gets to engine, they will fire with it, and doesnt possess the "lockup" capapbilities that ether does. I will prolly discover a few years down the road that it causes engine cancer in lab rats of something though, hopefully that will only be if your in california. randyp

[other dog]

I like to use Silicone Spray Lubricant, stead of ether, it makes them spin faster when gets to engine, they will fire with it, and doesnt possess the "lockup" capapbilities that ether does. I will prolly discover a few years down the road that it causes engine cancer in lab rats of something though, hopefully that will only be if your in california. randyp

Never heard of that,that's good to know. I've sprayed wd-40 in a chain saw carb. to get it started.