Hydroboost MC interchangeability?

[Z71paramedic]

I have hydroboost from a CUCV on my 72. The MC (although new from napa two months ago) was found to be leaking the day before I dropped it off to be shipped. I am planning to replace it when we are home in Ohio, but I was curious if a MC from a newer truck (ie the ones with the plastic reservoir/snap on cap) will work with the booster I have? I'd like to ensure I have no more leaks to ruin any more of the paint on my firewall No rush, just putting together a shopping list of stuff for my dad to pick up so we can slam some parts on when I'm in Ohio in a month.

 

[ashman]

obviously you know my experience on the subject, so take this with a grain of salt, but yes, I think they are interchangeable. in the process of deciding between hydroboost and 3/4 vacuum boost systems I ended up with several different MC from several different years. I pushed in the plunger on several of them to see if they would work and they all seemed to go in about the same distance. other than being able to bolt up, I can't think of any other variable that would matter.

I think you are safe to try a different year MC. the MC I am using with my hydroboost (from a '94) is a '72 1 ton. no issues to report.

 

[Z71paramedic]

obviously you know my experience on the subject, so take this with a grain of salt, but yes, I think they are interchangeable. in the process of deciding between hydroboost and 3/4 vacuum boost systems I ended up with several different MC from several different years. I pushed in the plunger on several of them to see if they would work and they all seemed to go in about the same distance. other than being able to bolt up, I can't think of any other variable that would matter.

I think you are safe to try a different year MC. the MC I am using with my hydroboost (from a '94) is a '72 1 ton. no issues to report.

I was just about to give this the ol "ttt" treatment...

Is the MC on yours the plastic reservoir type? I couldn't remember. I am just tired of BS leaks caused by too many cheap rubber gaskets everywhere so I figured I'd go with the newer style if possible.

 

[Z71paramedic]

Nevermind, I looked at your build. I guess I'll just wait until we're in Ohio and can go to the parts store and compare. I'll get it sorted out one way or another.

 

[76zimmer]

Sean, one issue I ran into in the 11th hour last year before Moab, was the replacement m/c (gave them the year and specified hydro unit) was the hydro pushrod wasn't long enough to push the piston in the m/c...I had to make a pushrod up that was about an inch longer....just something to watch for.

 

[Z71paramedic]

Sean, one issue I ran into in the 11th hour last year before Moab, was the replacement m/c (gave them the year and specified hydro unit) was the hydro pushrod wasn't long enough to push the piston in the m/c...I had to make a pushrod up that was about an inch longer....just something to watch for.

Ahh, right on. Thanks Dave I'll keep that in mind

 

[ashman]

Sean, one issue I ran into in the 11th hour last year before Moab, was the replacement m/c (gave them the year and specified hydro unit) was the hydro pushrod wasn't long enough to push the piston in the m/c...I had to make a pushrod up that was about an inch longer....just something to watch for.

yeah, I remembered reading that so that is why I was measuring the amount needed to fully compress my MC.

I didn't end up going with a plastic reservoir, but one of the ones I tested was like that.

when you pull off your current MC, just push the plunger in all the way and measure the distance, then make sure that whatever one you buy is the same distance and you'll be fine. (also, remember that the old one still has fluid in it. I forgot and found out the hard way )

 

[Z71paramedic]

Roger that