Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: prevostart on November 07, 2016, 09:18:13 am

Title: King Pins
Post by: prevostart on November 07, 2016, 09:18:13 am
Brake guy said king pins seem a little loose,What that involve, Any pictures?
Title: Re: King Pins
Post by: stump on November 07, 2016, 09:24:56 am
This is what I used in my Peterbilt. No reaming to size is needed. This type holds way more grease in it and last a long time. I have about 800,000 miles on this set in my Pete,and have a little play starting,so I'll be replacing them again in the near future. There is s video showing the installation somewhere.
Qwik Kit™ King Pin Kit | STEMCO (http://www.stemco.com/product/qwikkit/)

STEMCO Kaiser Qwik Kit Training - YouTube (http://youtu.be/S17x0BeA0qc)
Title: Re: King Pins
Post by: Chuck Pearson on November 07, 2016, 10:24:51 am
Brake guy said king pins seem a little loose,What that involve, Any pictures?

Are you having handling problems?  King pins are known for long, long service, seems unlikely they'd be worn out.  They've all got some play....
Title: Re: King Pins
Post by: wolfe10 on November 07, 2016, 10:31:12 am
Assume this is a Meritor axle.  If so, you can go to their website and download the shop manual for your axle.

There will be tolerance specs in it for king pin wear-- no need to guess or speculate. Replacing king pins and king pin bushings is not something most owners can do.  And, unless they were not greased, unlikely they would be worn out of spec.

Be aware that there IS an easy to do adjustment that can cause king pin play.  It will also be in the manual. King pin draw keys.  They are wedge shaped screws hold the king pins firmly in the steering knuckle.  They can easily be cleaned (the nut that holds them in place) and re-torqued.  As I recall on the front axle on the 1993 U240, draw key torque is 500 INCH- pounds (45 ft-lbs). So no big job to do. Just need to front wheels off the ground, clean the nut and torque them on the draw key. There are two on each side-- one on the front side of the knuckle, one on the back side of the knuckle.
Title: Re: King Pins
Post by: its toby on November 07, 2016, 09:07:08 pm
King pins aren't rocket science however they are a lot of slugging and can become an extreme amount of work if they don't go textbook.  If the adjustment doesn't work you will great a great variation in estimates. Some mechanics remove all of the parts from the spindle to make it easier to handle others wrestle it all off as an assembly to save the time.  The big issue is that very rarely do the king pins fall out of the axle when you undo everything and remove the wedges.  On a normal truck most people drive the kingpin down with a sledge but on a motorhome that isn't an option.  You will have to push the kingpin up through the assembly using a jack and the weight of the bus.  This will also require lots of heat and patience.  If the pin still wont budge then comes the real fun you cut the bearing out from between the spindle and the axle then cut the pin and push the spindle up and cut the pin above the axle.  This leads to the use of ingenuity, mechanics who do a lot of pins usually have some sort of a home made press that is essentially a huge ball joint press or remove the axle and put it in a very large hydraulic press usually at a large machine shop.  Some times you need to relieve the pressure by drilling or cutting a hole down the center of the pin. You also need to be careful that with all that heat and pressure you don't bend the axle.  If you end up replacing the kingpins take your time and find yourself a mechanic you trust who gives you answers that aren't too good to be true because they are honest.
Title: Re: King Pins
Post by: bbeane on November 07, 2016, 09:23:37 pm
Art where it me I would find a reputable truck spring and alignment shop and have them check/replace them as needed. They are a job to replace as someone said they can be a big problem. I ran a vehicle shop for a large construction company, the one thing that was outsourced was big truck steering and spring work just way to heavy to wrestle for no more than they charge to do it.
Title: Re: King Pins
Post by: John44 on November 08, 2016, 05:35:03 am
Just read up on king pins,remember to grease them with weight off the wheel.
Title: Re: King Pins
Post by: wolfe10 on November 08, 2016, 08:12:57 am
Just read up on king pins,remember to grease them with weight off the wheel.

Depends on make and model.  Some are greased with weight off wheels, others specify with wheels on the ground.

As you suggest, do what YOUR axle maker recommends.

This from a Meritor Manual:
Maintenance Manual 2
Front Non-Drive Steer Axles
All Meritor Conventional, Easy Steer Plus™ and MFS
Series

King Pins
Axles with Conventional Wheel Ends
1. Park the vehicle on a level surface. Block the wheels to prevent
the vehicle from moving. Set the parking brake.
2. Verify that the tires touch the ground. Do not raise the vehicle.
The full weight of the vehicle must be on the axle assembly.
Figure 9.5.
Title: Re: King Pins
Post by: prevostart on November 08, 2016, 09:22:16 am
Thanks'
Title: Re: King Pins
Post by: Tim Fiedler on November 08, 2016, 10:35:48 am
Add biocide as well when you fill
Title: Re: King Pins
Post by: John44 on November 15, 2016, 02:23:20 pm
Read up more on the kingpins,the "easy steer"ones that have the grease zirk on the top and bottom caps you can grease with
the weight on the wheels,the style that has the 2 zirks on the "side"has to have the weight off the wheels.