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4x4 Power King Build

3K views 17 replies 6 participants last post by  KennyP 
#1 · (Edited by Moderator)
I decided to start another thread, for this project. This is going to be the place where I make all of the posts about it until it is finished. I will copy all of the important posts from the other topic so people who may have missed them, can catch up to speed.

In the last few days I have been more actively looking for parts, and thinking about what I could use. There are very likely things that have been overlooked; my hope is that this thread will help get those gray areas sorted out. If we can all pull together and throw out any ideas we might have, I think that we will be able to come up with a very good design.
 
#2 · (Edited by Moderator)
Here is my idea for the drivetrain. Ideally I would be using one of the Power Kings with the duel transmissions, so that is how I drew the sketch.

View attachment 53770

This was my sketch of how I would get power to the front wheels. Since I will be using hubs that engage differently (explained in next post) there will just be a block bearing on each side of the gear instead.

View attachment 53769
 
#3 ·
I purchased a 1999 Polaris Scrambler 4x4 400 for the drive parts. I have removed all of the parts I will need from it for this project.

Here is a picture of the parts I will be using.

58A457FC-EB27-4AF4-B56B-47E205CEFB51-104


Cvans has the same four wheeler, and was able to copy some information from his manual about the operation and engagement of the front wheels.

"FINAL DRIVE SYSTEM SERVICE Demand 4 Operation - Mechanical Hubs, 1987-1988

Ramps
Hul
Cage
Roller
In the Polaris Demand 4 Drive System, the machine operates as a two wheel drive vehicle as long as the front wheel rotational speed remains greater than the front drive axle speed. If the rear wheels lose traction the front wheel rotational speed will decrease, caus­ing the front axle speed to become greater than the front wheel speed. The roller cage plungers contact the strut ramps, restricting the rotation of the roller cage and causing front wheel engagement. The roll­ers will then climb the ramps, becoming squeezed be­tween the ramps and the ring in the hub, and engaging the hub. ,Once the wheel hub, Demand 5 clutch as­sembly and axle are engaged, the front wheels will drive and will stay engaged until the rear wheel trac­tion is regained. When rear wheel traction is re­gained, the front wheels will overdrive the front drive shaft, pushing the clutch rollers toward the lower part of the cam and disengaging the Demand 4 clutch.
WARNING: It is important that the front and rear axle drive ratio and tire size are not changed. Changing this ratio will cause erratic engagement, which could result in serious injury or death.
Demand 4 Operation -
Electric Hubs, 1989 to Cur­rent
The electric hubs operate in much the same manner M the mechanical system described above. The only i Is that the clutch engages by means of an i magnet and armature plate instead of plung-i aprlngs and ramps. The electro magnet and ar-plate restrict the rotation of the Demand 4 i roller clutch assembly. The advantage of this I over the mechanical is that when the 4 wheel switch Is turned off the machine will have the ease of turning of a 2 wheel drive unit; and with the switch turned on, 4 wheel drive will be engaged."

Upon further research, I have found out that the front wheels are engaged when the machine looses 20% of its speed. For my application, I am thinking that it might be better to change this to about 10% speed loss. This means that less traction will have to be lost for the front wheels to engage. This is something I would like other opinions on.
 
#4 ·
This is my first idea of how to make the front axle. I would use an original PK axle (oragne), since I could then use the pivot, and the stops for where the axle stops pivoting. I would cut off the ends to what ever size I need. I would use a 3PT arm cut in half (blue), or to what ever size I need and weld it to the top of the PK axle. The spindles (gray) have a spot where the shocks originally slid into them. In these spots I would put a piece of pipe, round bar, or something else that I would then put a shaft onto the top of where it would go into the end of the 3PT arm. The differential (black) would be mounted onto a plate that with round bar (brown) welded to it. The round bar would go to the PK axle for support. There would also be round bar that would go to the ball joint on the bottom of the spindle.

One thing I am unsure of, is what size round bar to use. On on the ATV the "A" arms where made of 7/8" tubing with 1/8" walls. Since the A arms moved, a lot of the force was absorbed into the shocks. Since it will be mounted solid for my application, I need something much stronger. I am thinking maybe 3/4 solid bar for the brown parts in my picture. Do you guys think that is adequate?

View attachment 53771

While thinking about it, I found a problem with my design. Under the differential, there would be a plate that has all of the round bar coming off of it. But, if the round bar went to the ball joints on the bottom of the spindles, and more round bar that went to the PK axle, then I would have no way to put the spindles in! It would not go in, because the 3 point arm on top of the PK axle, would be welded in place, and the ends on the round bar would not be movable. I don't know if I explained this right, but I know that it would not work like that.

My solution is to have two plates under the differential. The top plate would have the bars that go to the PK axle for support, the bottom plate would have the bars that go to the ball joint. The bottom of the differential has 4 bolts with 9/16 heads that hold it down. I don't want all that pressure on four small bolts, so in addition to the four bolts in the differential I will put some larger bolts towards the edge more, their only purpose will be to hold the plates together. I would be able to take the bolts out and the top half would separate from the bottom half. Then, out come the spindles!
 
#5 ·
A yoke was suggested to eliminate the possibility of the front axle going back and forth. The back of the yoke would pivot on the cross-member that all PK frames have located under the clutch housing. This cross-member will have a shaft on it that the yoke will pivot on. This pivot will be directly in line with the pivot for the front axle. The yoke will most likely attach to the bars that go between the lower plate under the differential and the ball join on the bottom of the spindle, steering must be first planned before exact location can be calculated.

I drew up a sketch for the pivot where each side of the yoke will attach to the front axle. The blue is the part that will be welded solid to the front axle, in the decided location. This part will be shaped and of a different size depending on the location. Going through that piece will be a partially threaded shaft, with a "U" shape on the top (orange); the threaded portion of the shaft will have a castle nut (gray) with a cotter pin to hold it in place. The "U" will be where the end of the yoke (green) attaches. The yoke will either be attached by a pin or a bolt. This design will give the yoke the freedom it needs to move with the axle when it pivots.

View attachment 53772

After I drew this, and though about it, I questioned weather a pivot was needed. Can the yoke end be mounted to the front axle in an immobile fashion?
 
#6 ·
HI:

In looking at your parts and writings I am thinking you would want to look at the Honda front end to get some ideas. I am putting up a link to the parts drawings for the RT5000. Take a look at what they did. The front diff is bolted between the right and left axle housings. Then the shaft with the CV joints goes on and the final reduction with steering goes on last. If you study this you might get some ideas.I am thinking to mount the front diff on your existing axle and make the ends bolt on similat to the Honda. I could take some picks of the outer ends. The center is covered by frame parts for strength. You will need to have some support to the frame from the front wheels to utilize the pulling power. I will look at the service manual to see if there is a better picture in there.

http://www.boats.net/parts/search/Honda/Multi-Purpose%20Tractor/0/RT5000%20A%20MULTI-PURPOSE%20TRACTOR%2C%20JPN/FRONT%20FINAL%20CASE/parts.html

KURTEE
 
#7 ·
Looks like your moving along on your project ! The hubs that you have lock electrically ? The ones that aren't do they lock in both foward and reverse ? Trying to think of how they work ( the DB clicker hubs are in my mind lol ) When you build the transfer case will you weld a gear/pulley to the PKs driveshaft or maybe use the coupler as the spot to weld to ? Keep up the good work , Al
 
#8 ·
Looks like your moving along on your project ! The hubs that you have lock electrically ? The ones that aren't do they lock in both foward and reverse ? Trying to think of how they work ( the DB clicker hubs are in my mind lol ) When you build the transfer case will you weld a gear/pulley to the PKs driveshaft or maybe use the coupler as the spot to weld to ? Keep up the good work , Al
I am not sure where I am going to put the gear yet, most likely onto the driveshaft.

I will do my best to explain how the hubs work. If the machine is driving along, and there is no traction loss, the front axles will be turning 20% slower then the front wheels. Say the wheels are turning at 100 rpm, the axles will be turning at 80 rpm. When the rear tires loose traction the machine will go slower, this loss in speed will cause the front wheel rpm to drop. When the front wheel speed drops to 80 rpm then the hubs will lock, but only if the switch is on. (The numbers I used are only to exemplify how it works, I don't know the real numbers)

The way they lock is, there is a special type of clutch that when the front axle rpms and front wheel rpms fit the above scenario they lock in. They lock in because the difference in speed causes the rollers of the cluch to move up the sides of the inside part of the clutch being forced outward. This outward pressure locks the hubs to the axle and the front wheels are then engaged.

Here is a picture of of one of the clutches.

389B1C5A-DAE4-4DCF-B51A-81B7941EB93C-100


I don't know if I explained this clearly or not, but this is the best I can do.
 
#11 ·
I went to Home Depot the other day to get some pipe. I got two 1 1/4" pipes that where 12" long, they will go into the spindles where the shocks originally went.

Earlier this week, I ordered two CAT 1 replacement 3pt ends and they have already arrived! The ball and socket portion are bigger then I imagined, but I knew that they had a 7/8 hole, that would be perfect. The part coming off is shorter then I thought it was, but I think it will work fine as long as I weld it correctly. The bend that is in them will help accommodate for the angle that the spindles will be at.

42965B4F-1634-40B8-A03E-BF0D910C4632-234
 
#15 ·
Sorry, after I got to the reply page I forgot how you worded it; I thought I would just say that so I could give you an answer that could technically not be wrong. But... Now that you have went and said something about it, it basically defeated the purpose! Lol!
 
#17 ·
I went out and tried to do a test fit of the pipe into the spindle; the pipe is 0.003" to fat! I will have to have it turned down a little in a lathe.

I don't know what to call it exactly, I am going to call it the kingpin though. Whatever you want to call it, I made a sketch of it. The image in the PDF is sideways, it needs to be rotated clockwise one time (right click).

The 3 point arm end (blue) is welded to the topside of a PK axle (orange) that is cut to the the correct width. The strut (red) has two bolts on the backside that cause the strut to clamp down onto the piece of pipe (green) that goes inside of it. The pipe will have the partially threaded shaft that goes through the ball (red) in the 3 point arm end. On the threaded shaft will be a nut (black), the nut will be tightened down onto the ball, the ball and socket part of the 3 point arm will rotate when the wheels are turned.
 
#18 ·
Looks good, Ryan. I would call it a strut, myself.
 
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