I don't know why my Caterpillar dealership sent me three different parts breakdown for the hydraulic tilt cylinder supply lines, and no other options for my 1969 D8H 46A dozer... my lines run up through the blade frame they could not find this parts breakdown Arrangement anywhere., does anybody have the parts breakdown? that would be great, I'm trying to get correct replaceable lines.
There's three pair of lines. 1. First pair runs from bulkhead fitting in rear of blade arm (at trunion) to valve body. Hose Assembly 8S4932. Hose length 48.40". Angle Orientation 0 degrees. 2. Second pair runs inside blade arm from rear bulkhead to front bulkhead. Hose Assembly 8S4936. Hose length 139.50". Angle of Orientation 0 degrees. 3. The third pair runs from the front bulkhead to the tilt cylinder. There's two different hoses. Hose assembly 8S5620. Hose length 42.20" Angle Orientation 0 degrees. Hose assembly 8S4934. Hose length 26.20". Angle Orientation 0 degrees.
There's two 90 degree fittings in the front bulk head. The fittings are installed on the outside (top) of bulkhead. The third pair of hoses should be guarded. CAT used spring guard. I would use OEM guarding. The second pair of hoses inside the blade arm should also be guarded. Your choice, nylon sleeve (or fire hose) or plastic spiral hose guard. Failure to install hose guard around these hoses will result in excessive wear and the leak(s) everyone is talking about.
CAT should be able to print you a parts diagram if you tell them these hoses are part of the "8S6921 BLADE TILT CYLINDER LINES GROUP - Type 2. If you want to use a local hose shop, the hose is No. 8 (1/2") as mentioned previously. The three diagrams CAT sent you are probably titled as stated and are differentiated by Type 2, Type 3 and Type 4. Hose pairs 2 and 3 are the same length in all three "Types". Hose pair 1 for Type 3 changes to 37.80" and Type 4 changes to 38.47". I doubt this matters to you as you are only asking about Hose Pair No. 2 within the blade arm. These hoses are the same length for all three variations, Type 2, Type 3 and Type 4.
Hope this helps.