JD 450C blade pivot repair

[DBCSteve]

Anyone taken apart their six-way blade on a 450C? This is the 6405 blade. Mine has a fair amount of forward, backward and side-to-side play. My plan is to weld in wear plates (or hard face the existing plates) where the blade meets the frame on both sides (only one shim left on both sides, and lots of play), and maybe replace the center blade pivot.

Anyone have experience with the center pivot? The parts manual shows it as part # AU13937, pivot kit (on page 75-10 in PC 1420). I haven't taken the blade off yet, but I'd guess I just need to cut off the old one and weld the new one on.

Thanks for any experience you can provide.

[digitup2]

We always got a local welder to build up the pin in place lay the blade on it's face on the trailer and get someone experienced in building fifth wheel pins up .Don't remove the pin from it's original placement .Get it made just smaller than the hole on the backing plate that will be a bit larger than stock at this point.Even take the backing plate along with the blade to the welding shop and get them worked on together .DO NOT CUT THE PIN OUT!! .it will never stay in place after !. Digitup.

[DBCSteve]

We always got a local welder to build up the pin in place lay the blade on it's face on the trailer and get someone experienced in building fifth wheel pins up .Don't remove the pin from it's original placement .Get it made just smaller than the hole on the backing plate that will be a bit larger than stock at this point.Even take the backing plate along with the blade to the welding shop and get them worked on together .DO NOT CUT THE PIN OUT!! .it will never stay in place after !. Digitup.

Well, I finally got around to taking the blade apart, and an experienced welder is coming in to hard-face the wear surfaces and build up the pin. Here are pictures from yesterday, showing a true "exploded view":

http://gallery.me.com/macaulay.steve#100167

There is about 1/4 inch of slop in the pivot pin assembly. As to the angle wear surfaces, I am getting them hard-faced. This dozer only had one shim per side when I got it a few months ago, with about a 5/32 inch gap top to bottom (i.e. 5/16 gap resting on the bottom and measuring the gap at the top). I ordered two more shims per side so that I can more carefully adjust when I reassemble. Yep, I know I can go up to four shims per side, but that would be another couple of six packs I'd have to give up.

After removing the blade and angle frame I removed the water pump to get it rebuilt while the dozer is out of commission. In the Sierra Nevada foothills this is a good time of year to repair equipment since it is too dusty to work.

[digitup2]

I never built up the outer slide blade areas much . The pin and hole are the main thing and I built up the pin to fit the hole .Looks like you are getting things headed in the right direction though Steve .Good luck and keep us posted.you will find the tilt frame has rounded off at the wear plates so build that up flat as well .Keeping this flat will save your pin hole in the long run .Digitup.

[Tiger51]

Steve, those are great pictures of your 450C blade work - they really helped me. My 6405 blade is in parts right now to change the main pin etc and I'm not real clear on the side plate shim situation. Not really sure the purpose of the shims and the new side plates you welded on. Certainly they take up slack but I guess I'm unsure about how the system works.

[DBCSteve]

Steve, those are great pictures of your 450C blade work - they really helped me. My 6405 blade is in parts right now to change the main pin etc and I'm not real clear on the side plate shim situation. Not really sure the purpose of the shims and the new side plates you welded on. Certainly they take up slack but I guess I'm unsure about how the system works.

Sounds like you may have seen the updated pictures in that gallery. For those reading this, here it is again: http://gallery.me.com/macaulay.steve#10 ... &view=grid

The wear surfaces on both sides on the inside of the blade do just that -- they wear down. So I had a better-than-me welder weld some T1 plate to those surfaces. In the pictures you can see some bolt holes on the outside edge of these wear plates. These are the holes to which the "blade keepers" bolt. If you build up the wear surfaces, you need to add shims on the inside of the blade keepers so that the bolts don't bottom out before the setup tightens up (i.e. so the bolts are not bottoming out with the blade keepers still loose). With this setup, as the wear surfaces wear down, you just remove shims to tighten it back up until you remove the last shim -- at which time you repeat the process. I only use a dozer 100 hours or so a year, so I'm set for a long time.

The blade rotates on the pin that sticks out front on the angling frame, and it is the wear surfaces on the angling frame that fit between the blade keepers/shims and the blade wear surfaces. This sounds even confusing to me as I write it, but the pictures and the technical manual drawings help. I will add several of those TM pages to the photo gallery.

My blade rebuild was a complete success, and it works great! Unfortunately it's rained ever since so I can't play much for a while.

Steve

[Stan Disbrow]

Hi,

What's confusing is that most things with wear surfaces are designed such that you're adding shims to account for the wear, not the other way 'round!

Once one wraps one's wits around this scheme, then it makes perfect sense.

Of course, it helps to have (a) a machine and (b) the manual sitting in front of you!

Your photos pretty much cover the topic, though, so it's easily followed.

Later!

Stan