Sorry but I have another hydroboost question

[00gyrhed]

I am doing a HB conversion but I have lost the return spring rod assembly. I have a bunch of springs laying around but none of them are strong enough to force the rod out all the way without limiting travel somehow. I have no problem coming up with a method to retain the spring and cut one of the many pushrods I have to the right length.

So the question is short of going to a junkyard and pulling one will this spring force the rod that connects to the pedal all the way out of the device? Once I know that for sure I am good to go.

I only ask because it seems like quite a stiff spring is required to get that accomplished and the pictures I have seen of them they really don't look to have thick enough coils to push it completely out.

I really don't have time to go junkyard looking tomorrow.

 

[Viperwolf1]

What spring? No spring on my hydroboost brakes and I don't remember any inside the hydro unit either.

 

[00gyrhed]

I assume it is required to get proper pedal return. basically what I am missing is items 34-38 in the attached. all I nee is the right weight spring and I can make the rest work with things I already have.

exploded view of 76 mercury grand marquis.

 

[Viperwolf1]

I found a pic. Looks like this.

 

[00gyrhed]

From a long search of the internet it appears to be a part that isn't even cataloged. Someone told me to try a modern ford like a 2006 F250. That almost any HB be good even it I had to cut another rod.

 

[00gyrhed]

I assume thats a picture or yours

I found a pic. Looks like this.

when the spring is installed does it force the rod that connects to the brake pedal all the way out?

 

[00gyrhed]

In case anyone looks back at this or does a search because of a similar problem. What appears to be a satisfactory spring can be purchased at your local full service hardware store. A Servalite spring #50U is 3-1/2" long uncompressed and 1-1/2" compressed. It has a 15/16" outside diameter and 0.105" wire gauge. It is just strong enough to extend the operating rod all the way out with a properly size washers at each end and the tails ground flat to give it a little more clearance at full pedal.

Going to be a while before I can test it in a working system due to my work and travel schedule. I will repost if it doesn't work.

 

[tasker]

FIND ONE? might have a warranty replacement unit that i can send you for parts