Looking for a replacement 6-way blade trunnion mount for my early s/n D3-79U. This is a weldment that would be attached to the C-frame. (a few pictures included.) The blade "pivot" is achieved with the trunnion that is welded to the blade and kept in place by the trunnion cap which is NORMALLY attached by four 3/4" cap bolts. In my case this machine had suffered abuse like back-grading which bent one angle cylinder rod and broke the cap bolts. A number of field repairs involving drunken welding and other questionable "fixes" resulted in the nightmare I'm dealing with now. I believe I saw a reference on this forum a while back to an after-market plate that is to be welded to the C-frame to replace damaged parts. I have no other memory of a link or supplier, though a reference to a Louisiana dealer comes to mind' I have bought a replacement cap and a new trunnion, the trunnion is only to properly shim the cap adjustment if necessary. My blade's trunnion is still in good shape. If I can't locate a proper replacement for the blade-side mount I've ordered another cap with the idea of welding it in place after a lot of grinding and cutting. But it would be great if someone in this group knows of a source for the correct part, or a better fix. I have the original CAT parts book for the blade manual (3S LGP ad 3P Bulldozers - 85U1-up, 86U1-up), but no mention specifically for the mounting plate. Any leads or assistance would be most appreciated. Thanks, -Tom
It looks like the buggered up mounts in your 2nd and 3rd pic. that the new trunnion cap bolts to are welded on. I'd get new mounts drilled and tapped and cut the old ones off so you can weld the new mounts on. Would want to have the mounts held square so the bolts go in properly. Also wouldn't hurt to run a tap through the holes after welding.
I bought a second cap to weld onto the blade side which I will then install threacerts for the bolts. Some minor shimming between both caps (using the new trunnion as a gauge) should get me back to happy! Thanks for the idea, -Tom