70' GMC "Walter"

[skyjgmc]

Meet Walter he's a tired old gmc that I saved from the scrap heap. I picked it up not running for $500 towed it to my house and thats where this story starts.


maybe I should give a little history Ive always loved this body style of trucks I grew up driving a 70 gmc (mint green) just like this one on our dairy farm and we had a dog named Walter that always rode in the back (now you know where the name came from) anyways since I was little I have wanted another one, this one will be a father son project. My oldest is 11 and wants to restore and drive this truck to high school. we've got big plans for him but for now its just collecting parts and enjoying the **** out of it before we dismantle and rebuild. so sit back and hope its not a boring ride.

As I said earlier this truck was none running lady said its got no spark, so i ordered me up a new shiny cnc billet HEI dropped it in place and it fired right up didnt even need to adjust timing slapped a edelbrock 1406 carb on it and calleed it a day.


but then my son said "dad it looks like a grandpa truck!" so i found some flashy wheels and tires. Ah much better!!

then we procedeed to use the heck out of ol walter




then I got a crazy idea to put power disc brakes on him, and that when our problems started

I had spindles and rotors off of an old j10 truck i had everything bolted up fine

bought new gm half ton calipers and pads new hoses from 1 ton truck and new lines ran to the front wheels. new booster and master only thing I got used from a bone yard is the proportioning valve and left the rear drums alone. everything went smoothly and I gravity bled the brakes then the conventional way with one man pump/hold pedal while other loosens bleeder and it drove around great for a month but now after its sat for a day I get in and run down the road and I get a soft pedal and feels like its going to the floor never lose brakes just farther travel like air in the lines if I let off the pedal then its firm again for the remainder of the drive. backs lock up sometimes if I dynamite the brakes Im not losing fluid and I dont have any leaks. Im wondering if the proportioning valve is sticking and its not effectivly working its the only thing not brand new on the brake system. the truck stopped great before I just wanted power disc brakes. any help and insight would be appreciated.

and a little teaser of what we may do with the bed since its so trashed anyways. just an 8" bob.