The Stovebolt Site Forums The Shop Area Driveline Missing kingpin seal (3600 Kingpin Replacement)

The seal on the bottom of one kingpin in missing in action. Noticed this latest issue while greasing the suspension yesterday. Anyone have a fix that doesn't require total kingpin removal? I'm thinking some type split seal or a couple "cut to size" o-rings with a split spacer between them, or my current favorite idea; clean all the crud then apply a thin film of vaseline (release agent) to the king pin and spindle followed by filling the gap with a high quality polyurethane adhesive capped with a protective wrap of super duty tape.

I've just about got the parking brake working, guess this little detour is proof it's always something.

Oh, and Happy New Year!

RonR

Are you talking about the slightly convex metal slug which is driven into hole of the spindle where the end of the kinkpin is located?

No Sir. Your question made me do my DD. I discovered what I'm talking about is the kingpin thrust bearing as shown in fig. 2. Well crap.

In my weak defense my last experience with kingpins was about 50 years ago and then it was on VW sedans. They did have a dust seal at the bottom of the kingpin.

There's no real grease seal there. The pic shows a pair of steel washers with a bronze washer between them. Current King Pin kits use a ball bearing there instead. What's called a dust seal there is just that, It only keeps the big chunks out. If you pump it full of grease, it will ooze out of every crevice. Just wipe it down and drive on.

Got a minute in the shop today and made a few pictures. 1st shows the missing thrust bearing (that I now realize is missing the ball bearings) with the wheel off the floor. 2nd image shows the top of the kingpin with the truck's weight on the tire. The spindle has shifted and the new found clearance is now at the top of the kingpin. Third image shows the still good left kingpin with the complete trust bearing with all ball bearings in place along with the seal or dust cover intact.

If most of my driving was on paved roads like most folks, I'd do as klhansen suggested and just grease regularly and drive on. However I drive on a Lot of gravel roads, they're either dusty or muddy. Heck, it's a 1/4 mile of private gravel road from the house to the main paved road. That being the case I feel the need to replace kingpins, bushings and thrust bearings sooner rather than later.

Would it hurt to put it off a few hundred miles,,,,,,don't know.

RonR

If pounding up and down on the axle hasn't damaged things beyond fixing now (the spindle for instance) a few more miles probably won't hurt, but think about what's happening every time you hit a bump! Don't wait much longer!
Jerry

Jerry, my gut has been telling me exactly that. I've been asking around over the last few days for shop recommendations with small truck kingpin experience in central Arkansas. So far no leads. I'll likely strip the axle down and pull it. Then press out the old pin and bushings, press in the new bushings and carry the axle and spindles to a general machine shop and see if they'll ream the bushing to the pins keeping a common centerline on the bushings.

That's the current plan anyway.

RonR

Try to find a shop with a Sunnen hone, and a mandrel long enough to hone both bushings at once. That's the best way to be sure they are in an exact straight line. Also check Ebay for a "piloted king pin reamer" that keeps the holes in alignment as the bushings are reamed. I see them there occasionally.
Jerry

I ordered a king pin kit for my 5700, it's supposed to ship on the 5th, AC Delco from Summit. I couldn't get all of the dimensions from Summit but from the cross reference I think it's the right kit. No ball bearings for my application, just steel and bronze thrust washers as original, no dust boot, just overlapping steel washers. I am having a hard time getting one of the tie rod ends, Delco and Dorman have a listing but no stock. Moog has one that is close in dimensions so I might have to go that route. Hot Rod - do you think my local motor machine shop will be able to ream the new bushings to fit the new pins?

Required quite a bit of research but I have a kingpin kit on the way. Based on other's bad luck I only considered kits that showed component dimensions. One advantage of the exposed kingpin is I can get a caliper on it and it's .920 per my Old analog mike.

Went with a FCRC Machine kit, RPIS-30103. Shipping included it was $89.94 total.

Once it arrives the work begins.

RonR

Hey Moparguy, from what I have been reading about the half ton kingpins, it looks like the bushings fit without a press AND they say the bushings and pin are already machined to the correct tolerance. The shop manual for my year says this and I've seen it on a utube vid. You might be able to just do it all yourself. With mine I will have to ream the bushings to fit the pins from what I'm reading.

Buckshot, my research agrees with yours on the 3100 trucks. No help for me though since mine's a 3600 (3/4 ton). Even thought many vendor fitment charts show the 3100 (half ton) kingpins (that do not require reaming) working on 3600 trucks, I suspect they are wrong. At least on my truck that's the case.

Kingpins showed up yesterday and no way they'll go into the bushings without the bushings being honed or reamed. Looks like it's going to take a 2 or 3 thousandth cut to get a finger press fit of .001".

I'll break it all down this weekend and install the new bushings, then to the machine shop Monday and reassembly next week (I optimistically hope).

RonR

Well I wish you luck, I'm still waiting on my kit, I ordered it using the pin diameter and length, couldn't get specs on the bushing dimensions so I'm just hoping it's right. I think I will take the knuckles to my local machine shop for the reaming as long as the new pins aren't loose in the axle. I thought the 3/4 ton truck didn't use the ball bearing thrust so thats why I figured you were working on a 1/2 ton, sorry to assume.

Update and request for advice (read, HELP). Pulled the right side spindle, no big deal at all. Popped out the kingpin with a few serious blows from a 3 lb. ball peen hammer and big punch. Removing the top bushing was about a 5 or 10 minute job with a punch and same hammer. Bottom bushing after 10 minutes had moved about a 1/4". Wait, I've got a 30 ton press in the corner. After a few minutes getting set up, that was about a 2 minute job (after a Loud pop).

Jerry you were right about damage from rough roads causing a damaging hammer effect. Lucky it was the spindle and not the axle. My plan was to not install the kingpin bushings in that spindle ahd have the machine shop mill the damage out, and make a spacer the same thickness as the removed material. But, one of our members responded to my request of a replacement spindle so the repair is hopefully a moot point.

On the "Help" issue. The steering arm on the left side isn't wanting to come off. On the passenger side, after removing the castle nuts I screwed lug nuts on the two bottom bolts and with a few good swift blows drove them out, along with the brake backing plate and pulled the steering arm. That's not working on the drivers side. After a lot of cleaning, soaking with penetrating oil and many healthy blows with the BFH, no movement.

Heat, I'm to the point of using the ox/acy torch to heat the arm up to 400 perhaps 500 degrees and seeing if it'll free up. Thoughts?

The good news is the original tie rod ends and pitman arm ends look pretty good. I haven't taken them down yet, but the round ball/pins are still round with no obvious wear. I was all set to replace them but may not. The end cap was No problem to unscrew and everything looks Ok. Hopefully that'll still be the case when they're all clean and I can give the parts a good look.

RonR


added in edit. Heat, (not a lot) was the answer. Heat and about 15 minutes later and that part of the mission accomplished.

There are several new or "like new" Chevrolet king pin bushing reamers on Ebay today, some at ridiculously low prices. Check them out, and you just might find one that's the right diameter. It's also really easy to make a guide pilot for an adjustable hand reamer.
Jerry

Thanks for the headsup Jerry, just got in from visiting two local shops that could do the work in a respectable manner. Both were coming in between $200 and $300. That's with the bushings installed. Just miked the pins at .922 and installed bushings at .890, so with that in hand the plan is to add another tool (or reamer) to the box. This'll be a first time thing for me. Looks to my simple brain like the bushing ID needs to increase by .033 so make a .0165 cut or in reality something like .017. Shooting for a .001 or .002 clearance. Doable with a hand reamer by someone who's a total green hand?

RonR

Well, the project moves along....Slowly. After getting some expert coaching (Thanks Jerry!) I've ordered a NOS Snap-on reamer the correct size to do the job myself. Now if it'll just get here. It's not like I don't need to clean and paint and make adjustments till it gets here in a week. One benefit of the delay (I guess) is I'll finally get around to cleaning and flushing and adjusting the steering box and filling with TSC 00 Cotton Picker Spindle grease.

I may have a problem keeping this thing in the road from overcorrecting it'll steer so easy (one can only hope).

RonR

The NOS Bluepoint/Snapon kingpin bushing reamer showed up today. Big Thank You! to Jerry for giving me a heads up on this being available. You can see the part number, PN 922 in image 1 below. RR 922 is the actual reaming diameter of .922 which is perfect for the stock bushings and kingpin that is .921 diameter. The other images show how the RR 922 reams both bushings in parallel. The bottom pilot cutters start and center the process and the uppers complete the job. The tool diameter as shown in image 3 keeps the reamer centered as it passes through the bottom bushing.

This is my first attempt at kingpins and it's a fairly easy job with proper tools. I temporarily installed one spindle and the kingpin slides through the bushings and axel with slight finger pressure, zero binding through the full range of rotation. Clearance is .001.

My DD says 3100's don't require bushing reaming, everything bigger does.

I can't imagine anything better than the Snapon tool for this job, unless it's a healthy checkbook. Two local shops were upwards from $300. It's about an hour job once things are clean and bushings are ready to install and the reamer is in hand.

RonR

Wow, nice work, thank you for the info Moparguy. I'll have to start shopping for a reamer for mine. My pin diameter is 1.109" but I don't have anything torn down yet cuz it's drivable as is and the pin kit still isn't here. Where did you locate the reamer?

Ebay, I'm no expert but this one might be worth a look. Not sure about a handle to turn it and you'd have to use shim stock to keep it centered in the bushing you're not cutting. At least based on the knowledge Jerry shared. Hopefully he'll chime in.

Another, better option.

And another.

RonR

So the one you have is a non-adjustable, I've never used one so I don't know if a fixed diameter is better. Thank you for looking.

Yes it's non-adjustable. It's designed to do the job on trucks exactly like mine. Best it reames both bushings on the same axis so there's no binding due to the bushings not having the exact same centerline. As I understand things, you can get the same results with a different style reamer, just requires additional steps. Such as wrapping the shank of the reamer with shim stock so it stays centered in the bushing not being reamed.

RonR

Yeehaaaawwww!!! Job finished. Truck drives MUCH better. Steering is light and precise. Also, the front-end seems to be quieter while driving on our potholed roads.

I highly recommend this little project. Not that hard. Not that expensive. Returns are amazing.

RonR