Power Booster Push Rod Length?

[mydart270]

Hi and Hello

I have a 1968 Dodge Dart 270/SL-6 and need to know the push rod setting for an OEM Midland-Ross 8 1/2 in Power Booster and M/C that is aftermarket but fits the application for the Dodge Dart w/ 9 in shoe drums. The manual says 0.910-0.920 in using a Bendix M/C p/n 2225601.

Can I use the famous "H-Tool" and set the PB push rod length accordingly? The M/C appears to be a Raybestos p/n 2660809 with 1' bore. The "H-Tool" allows depth of M/C at one end (adjustable drill rod) and the other end of the drill rod automatically set for PB rod length when measured from surface of PB spacer and filter. I could forgo the "H-Tool" and measure with my calipers but a real PIA plus some math to account for a 1/16 in plate on the firewall because of a butchered install of a PB Booster. Of coarse the plate width would be factored into the H-tool measurement.

Also is there a p/n stamped on the linkage arm (from the brake pedal) to Power Booster pedal link? The parts catalog (Big Blue) shows p/n 2534 226, Hub and Lever, Power Brake.

Appreciate your comments and any guidance on the above.

Happy MOPAR and have a good day.

 

[Demonic]

Sadly, I don’t have an answer, BUT -

If you have the pushrod too long, it WILL cause the brakes to drag. I’d get some Play-Doh and set about.015” clearance.

 

[Dana67Dart]

Not sure the issue.

Be sure the push rod keeper is not in the mc piston hole. Then measure from the mounting surface if the mc to the depth of the piston.

Then subtract the 1/16" from that measurement.

Now adjust the pushrod accordingly

 

[mydart270]

Not sure the issue.

Be sure the push rod keeper is not in the mc piston hole. Then measure from the mounting surface if the mc to the depth of the piston.

Then subtract the 1/16" from that measurement.

Now adjust the pushrod accordingly

Thank you, Dana. Sorry....what is the M/C keeper?? Still knew at this expensive hobby but getting closer to the end.

Can you reflect on the PB pedal link? Last restoration house gave me an anodized pedal link after install of PB. I don't know which one is correct. It seems measurements are needed at the PB bracket to insure I have all linkages correct. Any thoughts??

Appreciate your comments and replies

 

[mydart270]

Thank you, Dana. Sorry....what is the M/C keeper?? Still knew at this expensive hobby but getting closer to the end.

Can you reflect on the PB pedal link? Last restoration house gave me an anodized pedal link after install of PB. I don't know which one is correct. It seems measurements are needed at the PB bracket to insure I have all linkages correct. Any thoughts??

Appreciate your comments and replies

Guess what? Figured it out. The M/C keeper is actually the piston retainer with screw. Lot to learn. Thx....Dana

 

[Dana67Dart]

Guess what? Figured it out. The M/C keeper is actually the piston retainer with screw

Well no.



Sorry I was not clear.

Some masters have a metal plate that keeps the piston in the mc. ( blue arrow)

Some have a snap ring inside the bore to keep the piston in the mc

(Red arrow)

I was referring to the small rubber part that is inserted into the hole in the piston to keep the manual brake pushrod inplace.

Red arrows point to holes that the plate screws to.

Green is the pushrod keeper before it is bottomed into the master cyl piston.

I may be wrong but on all power brake cars I have had there is no pushrod keeper the piston