Looking for a Ripper for D7 17A

[jsclampit]

I was wondering if there were any rippers that could be mounted on a D7 17A. Or any that could be adapted to fit on one of these machines. Thanks

[OzDozer]

jsclampit - The D7 17A, like all the Cats prior to the mid 1950's, was never designed to have any ripper mounted directly on the tractor .. the reason being, that rear-mount rippers place huge stresses on rear housings, and on the tractor chassis.

Cat tractors designed to have rear mount rippers, have the rear housing specially built and strengthened in the areas where the ripper backing plate mounts on the rear of the tractor, so that the tractors chassis can cope with the huge stresses involved.

Having said that .. nothing is impossible, and people have mounted rippers on old Cats. Once you find one that can be adapted, size-wise .. you need to fabricate a vertical ripper mounting plate that fits the rear housing of the 17A .. and then, also install a triangular-shaped plate, UNDER the tractor .. which plate is secured at the front, via the drawbar pull point pin .. and at the rear, by being securely bolted to the vertical mounting plate.

By doing so, you ensure that the ripper stresses are transferred evenly to both, the rear of the main housing, and the underside of the main housing, where the entire tractor drawbar pull is designed to be taken.

This setup of course, means you have to dispense with the entire original Cat drawbar, and mount a drawbar on the vertical mounting plate .. or if the drawbar is required for only light duty work .. on the ripper tube or box, where the shanks fit.

[Deas Plant.]

Hi, JSClampit.
I agree with Ozdozer's recipe above except that I'd add an extra wrinkle. If you make the draught triangle that attaches to the swinging drawbar pivot point a fraction shorter than the actual length required, you can add some shims between the triangle and the rear mounting plate to allow for future wear of the drawbar pin. This sort of set-up was used on some of the earlier Cat track loaders, 941, 951, etc., to reduce stress on the back end of the steering clutch case.

Havattitt!

[Old Magnet]

See if you can get some info on the "ATECO" line of aftermarket products. I'm pretty sure they made a unit for the 17A....and others.

[OzDozer]

Yes, Deas' additional info is good, and one area I forgot to mention. Using shims to keep the bottom plate tight, and effectively under slight tension, is highly advisable, and is a common arrangement.

[jsclampit]

Thanks for all of the useful information. I have been searching ATECO and not finding too much info. But I will keep looking. I thank all of you for the great ideas.