After replacing front brakes and bleeding system pedal goes to the floor

Good afternoon,

Did you bleed the rears as well?

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

Do you have ABS?

You may need to get a pressure bleeder to force the air out of the system. If all the air is removed then you lost the master cylinder.

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

Roy

Thanks Roy!, No ABS in this old truck. Have not bled the rear brakes, I will jump on that right away as well as redoing the front.

Okay, sounds like a plan.

Keep us updated.

Roy

Roy! Sent a message about the inspection and findings.

Sorry, did not show up here on the post.

Roy

Okay! There is no visible leak around the master cylinder, booster, or proportion valve. While my friend was pushing the pedal I could hear the piston moving in the master cylinder. I also noted that the fluid would jump when the pedal was pushed. Is this normal?

Yes, the piston seals may be bad internally.

Not quite sure of your reply. Are you thinking the seals inside the master cylinder may be worn? I have seen the repair kit on line is this worth the price? I only looking at this from the point that I bought the truck in 1994 and nothing has been changed in the way of booster, master cylinder, or proportion valve. I will still go ahead and re-bleed the brakes just to be sure.
Thanks,

Yes, the ones inside.

I would be leery about rebuilding. If the bore is pitted, it is no good. In the old days with cast iron masters, we could hone them and then use new seals. With today's aluminum cylinders, you cannot even clean them up.

I would replace the cylinder only.

Roy

Thank you Roy, I feel sure that the master would need replacing as it has been decades since the truck was bought. And nothing lasts forever.
Thanks,

You are welcome.

Always glad to help.

Roy